mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-17 21:29:20 +00:00
value, which is something that apparently isn't used much. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52158 91177308-0d34-0410-b5e6-96231b3b80d8
2142 lines
85 KiB
C++
2142 lines
85 KiB
C++
//===-- TargetLowering.cpp - Implement the TargetLowering class -----------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This implements the TargetLowering class.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Target/TargetAsmInfo.h"
|
|
#include "llvm/Target/TargetLowering.h"
|
|
#include "llvm/Target/TargetSubtarget.h"
|
|
#include "llvm/Target/TargetData.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
#include "llvm/Target/TargetRegisterInfo.h"
|
|
#include "llvm/GlobalVariable.h"
|
|
#include "llvm/DerivedTypes.h"
|
|
#include "llvm/CodeGen/MachineFrameInfo.h"
|
|
#include "llvm/CodeGen/SelectionDAG.h"
|
|
#include "llvm/ADT/StringExtras.h"
|
|
#include "llvm/ADT/STLExtras.h"
|
|
#include "llvm/Support/MathExtras.h"
|
|
using namespace llvm;
|
|
|
|
/// InitLibcallNames - Set default libcall names.
|
|
///
|
|
static void InitLibcallNames(const char **Names) {
|
|
Names[RTLIB::SHL_I32] = "__ashlsi3";
|
|
Names[RTLIB::SHL_I64] = "__ashldi3";
|
|
Names[RTLIB::SRL_I32] = "__lshrsi3";
|
|
Names[RTLIB::SRL_I64] = "__lshrdi3";
|
|
Names[RTLIB::SRA_I32] = "__ashrsi3";
|
|
Names[RTLIB::SRA_I64] = "__ashrdi3";
|
|
Names[RTLIB::MUL_I32] = "__mulsi3";
|
|
Names[RTLIB::MUL_I64] = "__muldi3";
|
|
Names[RTLIB::SDIV_I32] = "__divsi3";
|
|
Names[RTLIB::SDIV_I64] = "__divdi3";
|
|
Names[RTLIB::UDIV_I32] = "__udivsi3";
|
|
Names[RTLIB::UDIV_I64] = "__udivdi3";
|
|
Names[RTLIB::SREM_I32] = "__modsi3";
|
|
Names[RTLIB::SREM_I64] = "__moddi3";
|
|
Names[RTLIB::UREM_I32] = "__umodsi3";
|
|
Names[RTLIB::UREM_I64] = "__umoddi3";
|
|
Names[RTLIB::NEG_I32] = "__negsi2";
|
|
Names[RTLIB::NEG_I64] = "__negdi2";
|
|
Names[RTLIB::ADD_F32] = "__addsf3";
|
|
Names[RTLIB::ADD_F64] = "__adddf3";
|
|
Names[RTLIB::ADD_F80] = "__addxf3";
|
|
Names[RTLIB::ADD_PPCF128] = "__gcc_qadd";
|
|
Names[RTLIB::SUB_F32] = "__subsf3";
|
|
Names[RTLIB::SUB_F64] = "__subdf3";
|
|
Names[RTLIB::SUB_F80] = "__subxf3";
|
|
Names[RTLIB::SUB_PPCF128] = "__gcc_qsub";
|
|
Names[RTLIB::MUL_F32] = "__mulsf3";
|
|
Names[RTLIB::MUL_F64] = "__muldf3";
|
|
Names[RTLIB::MUL_F80] = "__mulxf3";
|
|
Names[RTLIB::MUL_PPCF128] = "__gcc_qmul";
|
|
Names[RTLIB::DIV_F32] = "__divsf3";
|
|
Names[RTLIB::DIV_F64] = "__divdf3";
|
|
Names[RTLIB::DIV_F80] = "__divxf3";
|
|
Names[RTLIB::DIV_PPCF128] = "__gcc_qdiv";
|
|
Names[RTLIB::REM_F32] = "fmodf";
|
|
Names[RTLIB::REM_F64] = "fmod";
|
|
Names[RTLIB::REM_F80] = "fmodl";
|
|
Names[RTLIB::REM_PPCF128] = "fmodl";
|
|
Names[RTLIB::POWI_F32] = "__powisf2";
|
|
Names[RTLIB::POWI_F64] = "__powidf2";
|
|
Names[RTLIB::POWI_F80] = "__powixf2";
|
|
Names[RTLIB::POWI_PPCF128] = "__powitf2";
|
|
Names[RTLIB::SQRT_F32] = "sqrtf";
|
|
Names[RTLIB::SQRT_F64] = "sqrt";
|
|
Names[RTLIB::SQRT_F80] = "sqrtl";
|
|
Names[RTLIB::SQRT_PPCF128] = "sqrtl";
|
|
Names[RTLIB::SIN_F32] = "sinf";
|
|
Names[RTLIB::SIN_F64] = "sin";
|
|
Names[RTLIB::SIN_F80] = "sinl";
|
|
Names[RTLIB::SIN_PPCF128] = "sinl";
|
|
Names[RTLIB::COS_F32] = "cosf";
|
|
Names[RTLIB::COS_F64] = "cos";
|
|
Names[RTLIB::COS_F80] = "cosl";
|
|
Names[RTLIB::COS_PPCF128] = "cosl";
|
|
Names[RTLIB::POW_F32] = "powf";
|
|
Names[RTLIB::POW_F64] = "pow";
|
|
Names[RTLIB::POW_F80] = "powl";
|
|
Names[RTLIB::POW_PPCF128] = "powl";
|
|
Names[RTLIB::FPEXT_F32_F64] = "__extendsfdf2";
|
|
Names[RTLIB::FPROUND_F64_F32] = "__truncdfsf2";
|
|
Names[RTLIB::FPTOSINT_F32_I32] = "__fixsfsi";
|
|
Names[RTLIB::FPTOSINT_F32_I64] = "__fixsfdi";
|
|
Names[RTLIB::FPTOSINT_F32_I128] = "__fixsfti";
|
|
Names[RTLIB::FPTOSINT_F64_I32] = "__fixdfsi";
|
|
Names[RTLIB::FPTOSINT_F64_I64] = "__fixdfdi";
|
|
Names[RTLIB::FPTOSINT_F64_I128] = "__fixdfti";
|
|
Names[RTLIB::FPTOSINT_F80_I64] = "__fixxfdi";
|
|
Names[RTLIB::FPTOSINT_F80_I128] = "__fixxfti";
|
|
Names[RTLIB::FPTOSINT_PPCF128_I64] = "__fixtfdi";
|
|
Names[RTLIB::FPTOSINT_PPCF128_I128] = "__fixtfti";
|
|
Names[RTLIB::FPTOUINT_F32_I32] = "__fixunssfsi";
|
|
Names[RTLIB::FPTOUINT_F32_I64] = "__fixunssfdi";
|
|
Names[RTLIB::FPTOUINT_F32_I128] = "__fixunssfti";
|
|
Names[RTLIB::FPTOUINT_F64_I32] = "__fixunsdfsi";
|
|
Names[RTLIB::FPTOUINT_F64_I64] = "__fixunsdfdi";
|
|
Names[RTLIB::FPTOUINT_F64_I128] = "__fixunsdfti";
|
|
Names[RTLIB::FPTOUINT_F80_I32] = "__fixunsxfsi";
|
|
Names[RTLIB::FPTOUINT_F80_I64] = "__fixunsxfdi";
|
|
Names[RTLIB::FPTOUINT_F80_I128] = "__fixunsxfti";
|
|
Names[RTLIB::FPTOUINT_PPCF128_I64] = "__fixunstfdi";
|
|
Names[RTLIB::FPTOUINT_PPCF128_I128] = "__fixunstfti";
|
|
Names[RTLIB::SINTTOFP_I32_F32] = "__floatsisf";
|
|
Names[RTLIB::SINTTOFP_I32_F64] = "__floatsidf";
|
|
Names[RTLIB::SINTTOFP_I64_F32] = "__floatdisf";
|
|
Names[RTLIB::SINTTOFP_I64_F64] = "__floatdidf";
|
|
Names[RTLIB::SINTTOFP_I64_F80] = "__floatdixf";
|
|
Names[RTLIB::SINTTOFP_I64_PPCF128] = "__floatditf";
|
|
Names[RTLIB::SINTTOFP_I128_F32] = "__floattisf";
|
|
Names[RTLIB::SINTTOFP_I128_F64] = "__floattidf";
|
|
Names[RTLIB::SINTTOFP_I128_F80] = "__floattixf";
|
|
Names[RTLIB::SINTTOFP_I128_PPCF128] = "__floattitf";
|
|
Names[RTLIB::UINTTOFP_I32_F32] = "__floatunsisf";
|
|
Names[RTLIB::UINTTOFP_I32_F64] = "__floatunsidf";
|
|
Names[RTLIB::UINTTOFP_I64_F32] = "__floatundisf";
|
|
Names[RTLIB::UINTTOFP_I64_F64] = "__floatundidf";
|
|
Names[RTLIB::OEQ_F32] = "__eqsf2";
|
|
Names[RTLIB::OEQ_F64] = "__eqdf2";
|
|
Names[RTLIB::UNE_F32] = "__nesf2";
|
|
Names[RTLIB::UNE_F64] = "__nedf2";
|
|
Names[RTLIB::OGE_F32] = "__gesf2";
|
|
Names[RTLIB::OGE_F64] = "__gedf2";
|
|
Names[RTLIB::OLT_F32] = "__ltsf2";
|
|
Names[RTLIB::OLT_F64] = "__ltdf2";
|
|
Names[RTLIB::OLE_F32] = "__lesf2";
|
|
Names[RTLIB::OLE_F64] = "__ledf2";
|
|
Names[RTLIB::OGT_F32] = "__gtsf2";
|
|
Names[RTLIB::OGT_F64] = "__gtdf2";
|
|
Names[RTLIB::UO_F32] = "__unordsf2";
|
|
Names[RTLIB::UO_F64] = "__unorddf2";
|
|
Names[RTLIB::O_F32] = "__unordsf2";
|
|
Names[RTLIB::O_F64] = "__unorddf2";
|
|
}
|
|
|
|
/// InitCmpLibcallCCs - Set default comparison libcall CC.
|
|
///
|
|
static void InitCmpLibcallCCs(ISD::CondCode *CCs) {
|
|
memset(CCs, ISD::SETCC_INVALID, sizeof(ISD::CondCode)*RTLIB::UNKNOWN_LIBCALL);
|
|
CCs[RTLIB::OEQ_F32] = ISD::SETEQ;
|
|
CCs[RTLIB::OEQ_F64] = ISD::SETEQ;
|
|
CCs[RTLIB::UNE_F32] = ISD::SETNE;
|
|
CCs[RTLIB::UNE_F64] = ISD::SETNE;
|
|
CCs[RTLIB::OGE_F32] = ISD::SETGE;
|
|
CCs[RTLIB::OGE_F64] = ISD::SETGE;
|
|
CCs[RTLIB::OLT_F32] = ISD::SETLT;
|
|
CCs[RTLIB::OLT_F64] = ISD::SETLT;
|
|
CCs[RTLIB::OLE_F32] = ISD::SETLE;
|
|
CCs[RTLIB::OLE_F64] = ISD::SETLE;
|
|
CCs[RTLIB::OGT_F32] = ISD::SETGT;
|
|
CCs[RTLIB::OGT_F64] = ISD::SETGT;
|
|
CCs[RTLIB::UO_F32] = ISD::SETNE;
|
|
CCs[RTLIB::UO_F64] = ISD::SETNE;
|
|
CCs[RTLIB::O_F32] = ISD::SETEQ;
|
|
CCs[RTLIB::O_F64] = ISD::SETEQ;
|
|
}
|
|
|
|
TargetLowering::TargetLowering(TargetMachine &tm)
|
|
: TM(tm), TD(TM.getTargetData()) {
|
|
assert(ISD::BUILTIN_OP_END <= OpActionsCapacity &&
|
|
"Fixed size array in TargetLowering is not large enough!");
|
|
// All operations default to being supported.
|
|
memset(OpActions, 0, sizeof(OpActions));
|
|
memset(LoadXActions, 0, sizeof(LoadXActions));
|
|
memset(TruncStoreActions, 0, sizeof(TruncStoreActions));
|
|
memset(IndexedModeActions, 0, sizeof(IndexedModeActions));
|
|
memset(ConvertActions, 0, sizeof(ConvertActions));
|
|
|
|
// Set default actions for various operations.
|
|
for (unsigned VT = 0; VT != (unsigned)MVT::LAST_VALUETYPE; ++VT) {
|
|
// Default all indexed load / store to expand.
|
|
for (unsigned IM = (unsigned)ISD::PRE_INC;
|
|
IM != (unsigned)ISD::LAST_INDEXED_MODE; ++IM) {
|
|
setIndexedLoadAction(IM, (MVT::SimpleValueType)VT, Expand);
|
|
setIndexedStoreAction(IM, (MVT::SimpleValueType)VT, Expand);
|
|
}
|
|
|
|
// These operations default to expand.
|
|
setOperationAction(ISD::FGETSIGN, (MVT::SimpleValueType)VT, Expand);
|
|
}
|
|
|
|
// Most targets ignore the @llvm.prefetch intrinsic.
|
|
setOperationAction(ISD::PREFETCH, MVT::Other, Expand);
|
|
|
|
// ConstantFP nodes default to expand. Targets can either change this to
|
|
// Legal, in which case all fp constants are legal, or use addLegalFPImmediate
|
|
// to optimize expansions for certain constants.
|
|
setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
|
|
setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
|
|
setOperationAction(ISD::ConstantFP, MVT::f80, Expand);
|
|
|
|
// Default ISD::TRAP to expand (which turns it into abort).
|
|
setOperationAction(ISD::TRAP, MVT::Other, Expand);
|
|
|
|
IsLittleEndian = TD->isLittleEndian();
|
|
UsesGlobalOffsetTable = false;
|
|
ShiftAmountTy = PointerTy = getValueType(TD->getIntPtrType());
|
|
ShiftAmtHandling = Undefined;
|
|
memset(RegClassForVT, 0,MVT::LAST_VALUETYPE*sizeof(TargetRegisterClass*));
|
|
memset(TargetDAGCombineArray, 0, array_lengthof(TargetDAGCombineArray));
|
|
maxStoresPerMemset = maxStoresPerMemcpy = maxStoresPerMemmove = 8;
|
|
allowUnalignedMemoryAccesses = false;
|
|
UseUnderscoreSetJmp = false;
|
|
UseUnderscoreLongJmp = false;
|
|
SelectIsExpensive = false;
|
|
IntDivIsCheap = false;
|
|
Pow2DivIsCheap = false;
|
|
StackPointerRegisterToSaveRestore = 0;
|
|
ExceptionPointerRegister = 0;
|
|
ExceptionSelectorRegister = 0;
|
|
SetCCResultContents = UndefinedSetCCResult;
|
|
SchedPreferenceInfo = SchedulingForLatency;
|
|
JumpBufSize = 0;
|
|
JumpBufAlignment = 0;
|
|
IfCvtBlockSizeLimit = 2;
|
|
IfCvtDupBlockSizeLimit = 0;
|
|
PrefLoopAlignment = 0;
|
|
|
|
InitLibcallNames(LibcallRoutineNames);
|
|
InitCmpLibcallCCs(CmpLibcallCCs);
|
|
|
|
// Tell Legalize whether the assembler supports DEBUG_LOC.
|
|
if (!TM.getTargetAsmInfo()->hasDotLocAndDotFile())
|
|
setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
|
|
}
|
|
|
|
TargetLowering::~TargetLowering() {}
|
|
|
|
/// computeRegisterProperties - Once all of the register classes are added,
|
|
/// this allows us to compute derived properties we expose.
|
|
void TargetLowering::computeRegisterProperties() {
|
|
assert(MVT::LAST_VALUETYPE <= 32 &&
|
|
"Too many value types for ValueTypeActions to hold!");
|
|
|
|
// Everything defaults to needing one register.
|
|
for (unsigned i = 0; i != MVT::LAST_VALUETYPE; ++i) {
|
|
NumRegistersForVT[i] = 1;
|
|
RegisterTypeForVT[i] = TransformToType[i] = (MVT::SimpleValueType)i;
|
|
}
|
|
// ...except isVoid, which doesn't need any registers.
|
|
NumRegistersForVT[MVT::isVoid] = 0;
|
|
|
|
// Find the largest integer register class.
|
|
unsigned LargestIntReg = MVT::LAST_INTEGER_VALUETYPE;
|
|
for (; RegClassForVT[LargestIntReg] == 0; --LargestIntReg)
|
|
assert(LargestIntReg != MVT::i1 && "No integer registers defined!");
|
|
|
|
// Every integer value type larger than this largest register takes twice as
|
|
// many registers to represent as the previous ValueType.
|
|
for (unsigned ExpandedReg = LargestIntReg + 1; ; ++ExpandedReg) {
|
|
MVT EVT = (MVT::SimpleValueType)ExpandedReg;
|
|
if (!EVT.isInteger())
|
|
break;
|
|
NumRegistersForVT[ExpandedReg] = 2*NumRegistersForVT[ExpandedReg-1];
|
|
RegisterTypeForVT[ExpandedReg] = (MVT::SimpleValueType)LargestIntReg;
|
|
TransformToType[ExpandedReg] = (MVT::SimpleValueType)(ExpandedReg - 1);
|
|
ValueTypeActions.setTypeAction(EVT, Expand);
|
|
}
|
|
|
|
// Inspect all of the ValueType's smaller than the largest integer
|
|
// register to see which ones need promotion.
|
|
unsigned LegalIntReg = LargestIntReg;
|
|
for (unsigned IntReg = LargestIntReg - 1;
|
|
IntReg >= (unsigned)MVT::i1; --IntReg) {
|
|
MVT IVT = (MVT::SimpleValueType)IntReg;
|
|
if (isTypeLegal(IVT)) {
|
|
LegalIntReg = IntReg;
|
|
} else {
|
|
RegisterTypeForVT[IntReg] = TransformToType[IntReg] =
|
|
(MVT::SimpleValueType)LegalIntReg;
|
|
ValueTypeActions.setTypeAction(IVT, Promote);
|
|
}
|
|
}
|
|
|
|
// ppcf128 type is really two f64's.
|
|
if (!isTypeLegal(MVT::ppcf128)) {
|
|
NumRegistersForVT[MVT::ppcf128] = 2*NumRegistersForVT[MVT::f64];
|
|
RegisterTypeForVT[MVT::ppcf128] = MVT::f64;
|
|
TransformToType[MVT::ppcf128] = MVT::f64;
|
|
ValueTypeActions.setTypeAction(MVT::ppcf128, Expand);
|
|
}
|
|
|
|
// Decide how to handle f64. If the target does not have native f64 support,
|
|
// expand it to i64 and we will be generating soft float library calls.
|
|
if (!isTypeLegal(MVT::f64)) {
|
|
NumRegistersForVT[MVT::f64] = NumRegistersForVT[MVT::i64];
|
|
RegisterTypeForVT[MVT::f64] = RegisterTypeForVT[MVT::i64];
|
|
TransformToType[MVT::f64] = MVT::i64;
|
|
ValueTypeActions.setTypeAction(MVT::f64, Expand);
|
|
}
|
|
|
|
// Decide how to handle f32. If the target does not have native support for
|
|
// f32, promote it to f64 if it is legal. Otherwise, expand it to i32.
|
|
if (!isTypeLegal(MVT::f32)) {
|
|
if (isTypeLegal(MVT::f64)) {
|
|
NumRegistersForVT[MVT::f32] = NumRegistersForVT[MVT::f64];
|
|
RegisterTypeForVT[MVT::f32] = RegisterTypeForVT[MVT::f64];
|
|
TransformToType[MVT::f32] = MVT::f64;
|
|
ValueTypeActions.setTypeAction(MVT::f32, Promote);
|
|
} else {
|
|
NumRegistersForVT[MVT::f32] = NumRegistersForVT[MVT::i32];
|
|
RegisterTypeForVT[MVT::f32] = RegisterTypeForVT[MVT::i32];
|
|
TransformToType[MVT::f32] = MVT::i32;
|
|
ValueTypeActions.setTypeAction(MVT::f32, Expand);
|
|
}
|
|
}
|
|
|
|
// Loop over all of the vector value types to see which need transformations.
|
|
for (unsigned i = MVT::FIRST_VECTOR_VALUETYPE;
|
|
i <= (unsigned)MVT::LAST_VECTOR_VALUETYPE; ++i) {
|
|
MVT VT = (MVT::SimpleValueType)i;
|
|
if (!isTypeLegal(VT)) {
|
|
MVT IntermediateVT, RegisterVT;
|
|
unsigned NumIntermediates;
|
|
NumRegistersForVT[i] =
|
|
getVectorTypeBreakdown(VT,
|
|
IntermediateVT, NumIntermediates,
|
|
RegisterVT);
|
|
RegisterTypeForVT[i] = RegisterVT;
|
|
TransformToType[i] = MVT::Other; // this isn't actually used
|
|
ValueTypeActions.setTypeAction(VT, Expand);
|
|
}
|
|
}
|
|
}
|
|
|
|
const char *TargetLowering::getTargetNodeName(unsigned Opcode) const {
|
|
return NULL;
|
|
}
|
|
|
|
|
|
MVT TargetLowering::getSetCCResultType(const SDOperand &) const {
|
|
return getValueType(TD->getIntPtrType());
|
|
}
|
|
|
|
|
|
/// getVectorTypeBreakdown - Vector types are broken down into some number of
|
|
/// legal first class types. For example, MVT::v8f32 maps to 2 MVT::v4f32
|
|
/// with Altivec or SSE1, or 8 promoted MVT::f64 values with the X86 FP stack.
|
|
/// Similarly, MVT::v2i64 turns into 4 MVT::i32 values with both PPC and X86.
|
|
///
|
|
/// This method returns the number of registers needed, and the VT for each
|
|
/// register. It also returns the VT and quantity of the intermediate values
|
|
/// before they are promoted/expanded.
|
|
///
|
|
unsigned TargetLowering::getVectorTypeBreakdown(MVT VT,
|
|
MVT &IntermediateVT,
|
|
unsigned &NumIntermediates,
|
|
MVT &RegisterVT) const {
|
|
// Figure out the right, legal destination reg to copy into.
|
|
unsigned NumElts = VT.getVectorNumElements();
|
|
MVT EltTy = VT.getVectorElementType();
|
|
|
|
unsigned NumVectorRegs = 1;
|
|
|
|
// FIXME: We don't support non-power-of-2-sized vectors for now. Ideally we
|
|
// could break down into LHS/RHS like LegalizeDAG does.
|
|
if (!isPowerOf2_32(NumElts)) {
|
|
NumVectorRegs = NumElts;
|
|
NumElts = 1;
|
|
}
|
|
|
|
// Divide the input until we get to a supported size. This will always
|
|
// end with a scalar if the target doesn't support vectors.
|
|
while (NumElts > 1 && !isTypeLegal(MVT::getVectorVT(EltTy, NumElts))) {
|
|
NumElts >>= 1;
|
|
NumVectorRegs <<= 1;
|
|
}
|
|
|
|
NumIntermediates = NumVectorRegs;
|
|
|
|
MVT NewVT = MVT::getVectorVT(EltTy, NumElts);
|
|
if (!isTypeLegal(NewVT))
|
|
NewVT = EltTy;
|
|
IntermediateVT = NewVT;
|
|
|
|
MVT DestVT = getTypeToTransformTo(NewVT);
|
|
RegisterVT = DestVT;
|
|
if (DestVT.bitsLT(NewVT)) {
|
|
// Value is expanded, e.g. i64 -> i16.
|
|
return NumVectorRegs*(NewVT.getSizeInBits()/DestVT.getSizeInBits());
|
|
} else {
|
|
// Otherwise, promotion or legal types use the same number of registers as
|
|
// the vector decimated to the appropriate level.
|
|
return NumVectorRegs;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/// getByValTypeAlignment - Return the desired alignment for ByVal aggregate
|
|
/// function arguments in the caller parameter area. This is the actual
|
|
/// alignment, not its logarithm.
|
|
unsigned TargetLowering::getByValTypeAlignment(const Type *Ty) const {
|
|
return TD->getCallFrameTypeAlignment(Ty);
|
|
}
|
|
|
|
SDOperand TargetLowering::getPICJumpTableRelocBase(SDOperand Table,
|
|
SelectionDAG &DAG) const {
|
|
if (usesGlobalOffsetTable())
|
|
return DAG.getNode(ISD::GLOBAL_OFFSET_TABLE, getPointerTy());
|
|
return Table;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Optimization Methods
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// ShrinkDemandedConstant - Check to see if the specified operand of the
|
|
/// specified instruction is a constant integer. If so, check to see if there
|
|
/// are any bits set in the constant that are not demanded. If so, shrink the
|
|
/// constant and return true.
|
|
bool TargetLowering::TargetLoweringOpt::ShrinkDemandedConstant(SDOperand Op,
|
|
const APInt &Demanded) {
|
|
// FIXME: ISD::SELECT, ISD::SELECT_CC
|
|
switch(Op.getOpcode()) {
|
|
default: break;
|
|
case ISD::AND:
|
|
case ISD::OR:
|
|
case ISD::XOR:
|
|
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op.getOperand(1)))
|
|
if (C->getAPIntValue().intersects(~Demanded)) {
|
|
MVT VT = Op.getValueType();
|
|
SDOperand New = DAG.getNode(Op.getOpcode(), VT, Op.getOperand(0),
|
|
DAG.getConstant(Demanded &
|
|
C->getAPIntValue(),
|
|
VT));
|
|
return CombineTo(Op, New);
|
|
}
|
|
break;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/// SimplifyDemandedBits - Look at Op. At this point, we know that only the
|
|
/// DemandedMask bits of the result of Op are ever used downstream. If we can
|
|
/// use this information to simplify Op, create a new simplified DAG node and
|
|
/// return true, returning the original and new nodes in Old and New. Otherwise,
|
|
/// analyze the expression and return a mask of KnownOne and KnownZero bits for
|
|
/// the expression (used to simplify the caller). The KnownZero/One bits may
|
|
/// only be accurate for those bits in the DemandedMask.
|
|
bool TargetLowering::SimplifyDemandedBits(SDOperand Op,
|
|
const APInt &DemandedMask,
|
|
APInt &KnownZero,
|
|
APInt &KnownOne,
|
|
TargetLoweringOpt &TLO,
|
|
unsigned Depth) const {
|
|
unsigned BitWidth = DemandedMask.getBitWidth();
|
|
assert(Op.getValueSizeInBits() == BitWidth &&
|
|
"Mask size mismatches value type size!");
|
|
APInt NewMask = DemandedMask;
|
|
|
|
// Don't know anything.
|
|
KnownZero = KnownOne = APInt(BitWidth, 0);
|
|
|
|
// Other users may use these bits.
|
|
if (!Op.Val->hasOneUse()) {
|
|
if (Depth != 0) {
|
|
// If not at the root, Just compute the KnownZero/KnownOne bits to
|
|
// simplify things downstream.
|
|
TLO.DAG.ComputeMaskedBits(Op, DemandedMask, KnownZero, KnownOne, Depth);
|
|
return false;
|
|
}
|
|
// If this is the root being simplified, allow it to have multiple uses,
|
|
// just set the NewMask to all bits.
|
|
NewMask = APInt::getAllOnesValue(BitWidth);
|
|
} else if (DemandedMask == 0) {
|
|
// Not demanding any bits from Op.
|
|
if (Op.getOpcode() != ISD::UNDEF)
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::UNDEF, Op.getValueType()));
|
|
return false;
|
|
} else if (Depth == 6) { // Limit search depth.
|
|
return false;
|
|
}
|
|
|
|
APInt KnownZero2, KnownOne2, KnownZeroOut, KnownOneOut;
|
|
switch (Op.getOpcode()) {
|
|
case ISD::Constant:
|
|
// We know all of the bits for a constant!
|
|
KnownOne = cast<ConstantSDNode>(Op)->getAPIntValue() & NewMask;
|
|
KnownZero = ~KnownOne & NewMask;
|
|
return false; // Don't fall through, will infinitely loop.
|
|
case ISD::AND:
|
|
// If the RHS is a constant, check to see if the LHS would be zero without
|
|
// using the bits from the RHS. Below, we use knowledge about the RHS to
|
|
// simplify the LHS, here we're using information from the LHS to simplify
|
|
// the RHS.
|
|
if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
|
|
APInt LHSZero, LHSOne;
|
|
TLO.DAG.ComputeMaskedBits(Op.getOperand(0), NewMask,
|
|
LHSZero, LHSOne, Depth+1);
|
|
// If the LHS already has zeros where RHSC does, this and is dead.
|
|
if ((LHSZero & NewMask) == (~RHSC->getAPIntValue() & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(0));
|
|
// If any of the set bits in the RHS are known zero on the LHS, shrink
|
|
// the constant.
|
|
if (TLO.ShrinkDemandedConstant(Op, ~LHSZero & NewMask))
|
|
return true;
|
|
}
|
|
|
|
if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero,
|
|
KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
if (SimplifyDemandedBits(Op.getOperand(0), ~KnownZero & NewMask,
|
|
KnownZero2, KnownOne2, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
|
|
|
|
// If all of the demanded bits are known one on one side, return the other.
|
|
// These bits cannot contribute to the result of the 'and'.
|
|
if ((NewMask & ~KnownZero2 & KnownOne) == (~KnownZero2 & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(0));
|
|
if ((NewMask & ~KnownZero & KnownOne2) == (~KnownZero & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(1));
|
|
// If all of the demanded bits in the inputs are known zeros, return zero.
|
|
if ((NewMask & (KnownZero|KnownZero2)) == NewMask)
|
|
return TLO.CombineTo(Op, TLO.DAG.getConstant(0, Op.getValueType()));
|
|
// If the RHS is a constant, see if we can simplify it.
|
|
if (TLO.ShrinkDemandedConstant(Op, ~KnownZero2 & NewMask))
|
|
return true;
|
|
|
|
// Output known-1 bits are only known if set in both the LHS & RHS.
|
|
KnownOne &= KnownOne2;
|
|
// Output known-0 are known to be clear if zero in either the LHS | RHS.
|
|
KnownZero |= KnownZero2;
|
|
break;
|
|
case ISD::OR:
|
|
if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero,
|
|
KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
if (SimplifyDemandedBits(Op.getOperand(0), ~KnownOne & NewMask,
|
|
KnownZero2, KnownOne2, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
|
|
|
|
// If all of the demanded bits are known zero on one side, return the other.
|
|
// These bits cannot contribute to the result of the 'or'.
|
|
if ((NewMask & ~KnownOne2 & KnownZero) == (~KnownOne2 & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(0));
|
|
if ((NewMask & ~KnownOne & KnownZero2) == (~KnownOne & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(1));
|
|
// If all of the potentially set bits on one side are known to be set on
|
|
// the other side, just use the 'other' side.
|
|
if ((NewMask & ~KnownZero & KnownOne2) == (~KnownZero & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(0));
|
|
if ((NewMask & ~KnownZero2 & KnownOne) == (~KnownZero2 & NewMask))
|
|
return TLO.CombineTo(Op, Op.getOperand(1));
|
|
// If the RHS is a constant, see if we can simplify it.
|
|
if (TLO.ShrinkDemandedConstant(Op, NewMask))
|
|
return true;
|
|
|
|
// Output known-0 bits are only known if clear in both the LHS & RHS.
|
|
KnownZero &= KnownZero2;
|
|
// Output known-1 are known to be set if set in either the LHS | RHS.
|
|
KnownOne |= KnownOne2;
|
|
break;
|
|
case ISD::XOR:
|
|
if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero,
|
|
KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
if (SimplifyDemandedBits(Op.getOperand(0), NewMask, KnownZero2,
|
|
KnownOne2, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
|
|
|
|
// If all of the demanded bits are known zero on one side, return the other.
|
|
// These bits cannot contribute to the result of the 'xor'.
|
|
if ((KnownZero & NewMask) == NewMask)
|
|
return TLO.CombineTo(Op, Op.getOperand(0));
|
|
if ((KnownZero2 & NewMask) == NewMask)
|
|
return TLO.CombineTo(Op, Op.getOperand(1));
|
|
|
|
// If all of the unknown bits are known to be zero on one side or the other
|
|
// (but not both) turn this into an *inclusive* or.
|
|
// e.g. (A & C1)^(B & C2) -> (A & C1)|(B & C2) iff C1&C2 == 0
|
|
if ((NewMask & ~KnownZero & ~KnownZero2) == 0)
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::OR, Op.getValueType(),
|
|
Op.getOperand(0),
|
|
Op.getOperand(1)));
|
|
|
|
// Output known-0 bits are known if clear or set in both the LHS & RHS.
|
|
KnownZeroOut = (KnownZero & KnownZero2) | (KnownOne & KnownOne2);
|
|
// Output known-1 are known to be set if set in only one of the LHS, RHS.
|
|
KnownOneOut = (KnownZero & KnownOne2) | (KnownOne & KnownZero2);
|
|
|
|
// If all of the demanded bits on one side are known, and all of the set
|
|
// bits on that side are also known to be set on the other side, turn this
|
|
// into an AND, as we know the bits will be cleared.
|
|
// e.g. (X | C1) ^ C2 --> (X | C1) & ~C2 iff (C1&C2) == C2
|
|
if ((NewMask & (KnownZero|KnownOne)) == NewMask) { // all known
|
|
if ((KnownOne & KnownOne2) == KnownOne) {
|
|
MVT VT = Op.getValueType();
|
|
SDOperand ANDC = TLO.DAG.getConstant(~KnownOne & NewMask, VT);
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::AND, VT, Op.getOperand(0),
|
|
ANDC));
|
|
}
|
|
}
|
|
|
|
// If the RHS is a constant, see if we can simplify it.
|
|
// for XOR, we prefer to force bits to 1 if they will make a -1.
|
|
// if we can't force bits, try to shrink constant
|
|
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
|
|
APInt Expanded = C->getAPIntValue() | (~NewMask);
|
|
// if we can expand it to have all bits set, do it
|
|
if (Expanded.isAllOnesValue()) {
|
|
if (Expanded != C->getAPIntValue()) {
|
|
MVT VT = Op.getValueType();
|
|
SDOperand New = TLO.DAG.getNode(Op.getOpcode(), VT, Op.getOperand(0),
|
|
TLO.DAG.getConstant(Expanded, VT));
|
|
return TLO.CombineTo(Op, New);
|
|
}
|
|
// if it already has all the bits set, nothing to change
|
|
// but don't shrink either!
|
|
} else if (TLO.ShrinkDemandedConstant(Op, NewMask)) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
KnownZero = KnownZeroOut;
|
|
KnownOne = KnownOneOut;
|
|
break;
|
|
case ISD::SELECT:
|
|
if (SimplifyDemandedBits(Op.getOperand(2), NewMask, KnownZero,
|
|
KnownOne, TLO, Depth+1))
|
|
return true;
|
|
if (SimplifyDemandedBits(Op.getOperand(1), NewMask, KnownZero2,
|
|
KnownOne2, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
|
|
|
|
// If the operands are constants, see if we can simplify them.
|
|
if (TLO.ShrinkDemandedConstant(Op, NewMask))
|
|
return true;
|
|
|
|
// Only known if known in both the LHS and RHS.
|
|
KnownOne &= KnownOne2;
|
|
KnownZero &= KnownZero2;
|
|
break;
|
|
case ISD::SELECT_CC:
|
|
if (SimplifyDemandedBits(Op.getOperand(3), NewMask, KnownZero,
|
|
KnownOne, TLO, Depth+1))
|
|
return true;
|
|
if (SimplifyDemandedBits(Op.getOperand(2), NewMask, KnownZero2,
|
|
KnownOne2, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
|
|
|
|
// If the operands are constants, see if we can simplify them.
|
|
if (TLO.ShrinkDemandedConstant(Op, NewMask))
|
|
return true;
|
|
|
|
// Only known if known in both the LHS and RHS.
|
|
KnownOne &= KnownOne2;
|
|
KnownZero &= KnownZero2;
|
|
break;
|
|
case ISD::SHL:
|
|
if (ConstantSDNode *SA = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
|
|
unsigned ShAmt = SA->getValue();
|
|
SDOperand InOp = Op.getOperand(0);
|
|
|
|
// If the shift count is an invalid immediate, don't do anything.
|
|
if (ShAmt >= BitWidth)
|
|
break;
|
|
|
|
// If this is ((X >>u C1) << ShAmt), see if we can simplify this into a
|
|
// single shift. We can do this if the bottom bits (which are shifted
|
|
// out) are never demanded.
|
|
if (InOp.getOpcode() == ISD::SRL &&
|
|
isa<ConstantSDNode>(InOp.getOperand(1))) {
|
|
if (ShAmt && (NewMask & APInt::getLowBitsSet(BitWidth, ShAmt)) == 0) {
|
|
unsigned C1 = cast<ConstantSDNode>(InOp.getOperand(1))->getValue();
|
|
unsigned Opc = ISD::SHL;
|
|
int Diff = ShAmt-C1;
|
|
if (Diff < 0) {
|
|
Diff = -Diff;
|
|
Opc = ISD::SRL;
|
|
}
|
|
|
|
SDOperand NewSA =
|
|
TLO.DAG.getConstant(Diff, Op.getOperand(1).getValueType());
|
|
MVT VT = Op.getValueType();
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(Opc, VT,
|
|
InOp.getOperand(0), NewSA));
|
|
}
|
|
}
|
|
|
|
if (SimplifyDemandedBits(Op.getOperand(0), NewMask.lshr(ShAmt),
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
KnownZero <<= SA->getValue();
|
|
KnownOne <<= SA->getValue();
|
|
// low bits known zero.
|
|
KnownZero |= APInt::getLowBitsSet(BitWidth, SA->getValue());
|
|
}
|
|
break;
|
|
case ISD::SRL:
|
|
if (ConstantSDNode *SA = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
|
|
MVT VT = Op.getValueType();
|
|
unsigned ShAmt = SA->getValue();
|
|
unsigned VTSize = VT.getSizeInBits();
|
|
SDOperand InOp = Op.getOperand(0);
|
|
|
|
// If the shift count is an invalid immediate, don't do anything.
|
|
if (ShAmt >= BitWidth)
|
|
break;
|
|
|
|
// If this is ((X << C1) >>u ShAmt), see if we can simplify this into a
|
|
// single shift. We can do this if the top bits (which are shifted out)
|
|
// are never demanded.
|
|
if (InOp.getOpcode() == ISD::SHL &&
|
|
isa<ConstantSDNode>(InOp.getOperand(1))) {
|
|
if (ShAmt && (NewMask & APInt::getHighBitsSet(VTSize, ShAmt)) == 0) {
|
|
unsigned C1 = cast<ConstantSDNode>(InOp.getOperand(1))->getValue();
|
|
unsigned Opc = ISD::SRL;
|
|
int Diff = ShAmt-C1;
|
|
if (Diff < 0) {
|
|
Diff = -Diff;
|
|
Opc = ISD::SHL;
|
|
}
|
|
|
|
SDOperand NewSA =
|
|
TLO.DAG.getConstant(Diff, Op.getOperand(1).getValueType());
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(Opc, VT,
|
|
InOp.getOperand(0), NewSA));
|
|
}
|
|
}
|
|
|
|
// Compute the new bits that are at the top now.
|
|
if (SimplifyDemandedBits(InOp, (NewMask << ShAmt),
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
KnownZero = KnownZero.lshr(ShAmt);
|
|
KnownOne = KnownOne.lshr(ShAmt);
|
|
|
|
APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt);
|
|
KnownZero |= HighBits; // High bits known zero.
|
|
}
|
|
break;
|
|
case ISD::SRA:
|
|
if (ConstantSDNode *SA = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
|
|
MVT VT = Op.getValueType();
|
|
unsigned ShAmt = SA->getValue();
|
|
|
|
// If the shift count is an invalid immediate, don't do anything.
|
|
if (ShAmt >= BitWidth)
|
|
break;
|
|
|
|
APInt InDemandedMask = (NewMask << ShAmt);
|
|
|
|
// If any of the demanded bits are produced by the sign extension, we also
|
|
// demand the input sign bit.
|
|
APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt);
|
|
if (HighBits.intersects(NewMask))
|
|
InDemandedMask |= APInt::getSignBit(VT.getSizeInBits());
|
|
|
|
if (SimplifyDemandedBits(Op.getOperand(0), InDemandedMask,
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
KnownZero = KnownZero.lshr(ShAmt);
|
|
KnownOne = KnownOne.lshr(ShAmt);
|
|
|
|
// Handle the sign bit, adjusted to where it is now in the mask.
|
|
APInt SignBit = APInt::getSignBit(BitWidth).lshr(ShAmt);
|
|
|
|
// If the input sign bit is known to be zero, or if none of the top bits
|
|
// are demanded, turn this into an unsigned shift right.
|
|
if (KnownZero.intersects(SignBit) || (HighBits & ~NewMask) == HighBits) {
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SRL, VT, Op.getOperand(0),
|
|
Op.getOperand(1)));
|
|
} else if (KnownOne.intersects(SignBit)) { // New bits are known one.
|
|
KnownOne |= HighBits;
|
|
}
|
|
}
|
|
break;
|
|
case ISD::SIGN_EXTEND_INREG: {
|
|
MVT EVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
|
|
|
|
// Sign extension. Compute the demanded bits in the result that are not
|
|
// present in the input.
|
|
APInt NewBits = APInt::getHighBitsSet(BitWidth,
|
|
BitWidth - EVT.getSizeInBits()) &
|
|
NewMask;
|
|
|
|
// If none of the extended bits are demanded, eliminate the sextinreg.
|
|
if (NewBits == 0)
|
|
return TLO.CombineTo(Op, Op.getOperand(0));
|
|
|
|
APInt InSignBit = APInt::getSignBit(EVT.getSizeInBits());
|
|
InSignBit.zext(BitWidth);
|
|
APInt InputDemandedBits = APInt::getLowBitsSet(BitWidth,
|
|
EVT.getSizeInBits()) &
|
|
NewMask;
|
|
|
|
// Since the sign extended bits are demanded, we know that the sign
|
|
// bit is demanded.
|
|
InputDemandedBits |= InSignBit;
|
|
|
|
if (SimplifyDemandedBits(Op.getOperand(0), InputDemandedBits,
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
|
|
// If the sign bit of the input is known set or clear, then we know the
|
|
// top bits of the result.
|
|
|
|
// If the input sign bit is known zero, convert this into a zero extension.
|
|
if (KnownZero.intersects(InSignBit))
|
|
return TLO.CombineTo(Op,
|
|
TLO.DAG.getZeroExtendInReg(Op.getOperand(0), EVT));
|
|
|
|
if (KnownOne.intersects(InSignBit)) { // Input sign bit known set
|
|
KnownOne |= NewBits;
|
|
KnownZero &= ~NewBits;
|
|
} else { // Input sign bit unknown
|
|
KnownZero &= ~NewBits;
|
|
KnownOne &= ~NewBits;
|
|
}
|
|
break;
|
|
}
|
|
case ISD::ZERO_EXTEND: {
|
|
unsigned OperandBitWidth = Op.getOperand(0).getValueSizeInBits();
|
|
APInt InMask = NewMask;
|
|
InMask.trunc(OperandBitWidth);
|
|
|
|
// If none of the top bits are demanded, convert this into an any_extend.
|
|
APInt NewBits =
|
|
APInt::getHighBitsSet(BitWidth, BitWidth - OperandBitWidth) & NewMask;
|
|
if (!NewBits.intersects(NewMask))
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::ANY_EXTEND,
|
|
Op.getValueType(),
|
|
Op.getOperand(0)));
|
|
|
|
if (SimplifyDemandedBits(Op.getOperand(0), InMask,
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
KnownZero.zext(BitWidth);
|
|
KnownOne.zext(BitWidth);
|
|
KnownZero |= NewBits;
|
|
break;
|
|
}
|
|
case ISD::SIGN_EXTEND: {
|
|
MVT InVT = Op.getOperand(0).getValueType();
|
|
unsigned InBits = InVT.getSizeInBits();
|
|
APInt InMask = APInt::getLowBitsSet(BitWidth, InBits);
|
|
APInt InSignBit = APInt::getBitsSet(BitWidth, InBits - 1, InBits);
|
|
APInt NewBits = ~InMask & NewMask;
|
|
|
|
// If none of the top bits are demanded, convert this into an any_extend.
|
|
if (NewBits == 0)
|
|
return TLO.CombineTo(Op,TLO.DAG.getNode(ISD::ANY_EXTEND,Op.getValueType(),
|
|
Op.getOperand(0)));
|
|
|
|
// Since some of the sign extended bits are demanded, we know that the sign
|
|
// bit is demanded.
|
|
APInt InDemandedBits = InMask & NewMask;
|
|
InDemandedBits |= InSignBit;
|
|
InDemandedBits.trunc(InBits);
|
|
|
|
if (SimplifyDemandedBits(Op.getOperand(0), InDemandedBits, KnownZero,
|
|
KnownOne, TLO, Depth+1))
|
|
return true;
|
|
KnownZero.zext(BitWidth);
|
|
KnownOne.zext(BitWidth);
|
|
|
|
// If the sign bit is known zero, convert this to a zero extend.
|
|
if (KnownZero.intersects(InSignBit))
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::ZERO_EXTEND,
|
|
Op.getValueType(),
|
|
Op.getOperand(0)));
|
|
|
|
// If the sign bit is known one, the top bits match.
|
|
if (KnownOne.intersects(InSignBit)) {
|
|
KnownOne |= NewBits;
|
|
KnownZero &= ~NewBits;
|
|
} else { // Otherwise, top bits aren't known.
|
|
KnownOne &= ~NewBits;
|
|
KnownZero &= ~NewBits;
|
|
}
|
|
break;
|
|
}
|
|
case ISD::ANY_EXTEND: {
|
|
unsigned OperandBitWidth = Op.getOperand(0).getValueSizeInBits();
|
|
APInt InMask = NewMask;
|
|
InMask.trunc(OperandBitWidth);
|
|
if (SimplifyDemandedBits(Op.getOperand(0), InMask,
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
KnownZero.zext(BitWidth);
|
|
KnownOne.zext(BitWidth);
|
|
break;
|
|
}
|
|
case ISD::TRUNCATE: {
|
|
// Simplify the input, using demanded bit information, and compute the known
|
|
// zero/one bits live out.
|
|
APInt TruncMask = NewMask;
|
|
TruncMask.zext(Op.getOperand(0).getValueSizeInBits());
|
|
if (SimplifyDemandedBits(Op.getOperand(0), TruncMask,
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
KnownZero.trunc(BitWidth);
|
|
KnownOne.trunc(BitWidth);
|
|
|
|
// If the input is only used by this truncate, see if we can shrink it based
|
|
// on the known demanded bits.
|
|
if (Op.getOperand(0).Val->hasOneUse()) {
|
|
SDOperand In = Op.getOperand(0);
|
|
unsigned InBitWidth = In.getValueSizeInBits();
|
|
switch (In.getOpcode()) {
|
|
default: break;
|
|
case ISD::SRL:
|
|
// Shrink SRL by a constant if none of the high bits shifted in are
|
|
// demanded.
|
|
if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(In.getOperand(1))){
|
|
APInt HighBits = APInt::getHighBitsSet(InBitWidth,
|
|
InBitWidth - BitWidth);
|
|
HighBits = HighBits.lshr(ShAmt->getValue());
|
|
HighBits.trunc(BitWidth);
|
|
|
|
if (ShAmt->getValue() < BitWidth && !(HighBits & NewMask)) {
|
|
// None of the shifted in bits are needed. Add a truncate of the
|
|
// shift input, then shift it.
|
|
SDOperand NewTrunc = TLO.DAG.getNode(ISD::TRUNCATE,
|
|
Op.getValueType(),
|
|
In.getOperand(0));
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SRL,Op.getValueType(),
|
|
NewTrunc, In.getOperand(1)));
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
break;
|
|
}
|
|
case ISD::AssertZext: {
|
|
MVT VT = cast<VTSDNode>(Op.getOperand(1))->getVT();
|
|
APInt InMask = APInt::getLowBitsSet(BitWidth,
|
|
VT.getSizeInBits());
|
|
if (SimplifyDemandedBits(Op.getOperand(0), InMask & NewMask,
|
|
KnownZero, KnownOne, TLO, Depth+1))
|
|
return true;
|
|
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
|
|
KnownZero |= ~InMask & NewMask;
|
|
break;
|
|
}
|
|
case ISD::BIT_CONVERT:
|
|
#if 0
|
|
// If this is an FP->Int bitcast and if the sign bit is the only thing that
|
|
// is demanded, turn this into a FGETSIGN.
|
|
if (NewMask == MVT::getIntegerVTSignBit(Op.getValueType()) &&
|
|
MVT::isFloatingPoint(Op.getOperand(0).getValueType()) &&
|
|
!MVT::isVector(Op.getOperand(0).getValueType())) {
|
|
// Only do this xform if FGETSIGN is valid or if before legalize.
|
|
if (!TLO.AfterLegalize ||
|
|
isOperationLegal(ISD::FGETSIGN, Op.getValueType())) {
|
|
// Make a FGETSIGN + SHL to move the sign bit into the appropriate
|
|
// place. We expect the SHL to be eliminated by other optimizations.
|
|
SDOperand Sign = TLO.DAG.getNode(ISD::FGETSIGN, Op.getValueType(),
|
|
Op.getOperand(0));
|
|
unsigned ShVal = Op.getValueType().getSizeInBits()-1;
|
|
SDOperand ShAmt = TLO.DAG.getConstant(ShVal, getShiftAmountTy());
|
|
return TLO.CombineTo(Op, TLO.DAG.getNode(ISD::SHL, Op.getValueType(),
|
|
Sign, ShAmt));
|
|
}
|
|
}
|
|
#endif
|
|
break;
|
|
default:
|
|
// Just use ComputeMaskedBits to compute output bits.
|
|
TLO.DAG.ComputeMaskedBits(Op, NewMask, KnownZero, KnownOne, Depth);
|
|
break;
|
|
}
|
|
|
|
// If we know the value of all of the demanded bits, return this as a
|
|
// constant.
|
|
if ((NewMask & (KnownZero|KnownOne)) == NewMask)
|
|
return TLO.CombineTo(Op, TLO.DAG.getConstant(KnownOne, Op.getValueType()));
|
|
|
|
return false;
|
|
}
|
|
|
|
/// computeMaskedBitsForTargetNode - Determine which of the bits specified
|
|
/// in Mask are known to be either zero or one and return them in the
|
|
/// KnownZero/KnownOne bitsets.
|
|
void TargetLowering::computeMaskedBitsForTargetNode(const SDOperand Op,
|
|
const APInt &Mask,
|
|
APInt &KnownZero,
|
|
APInt &KnownOne,
|
|
const SelectionDAG &DAG,
|
|
unsigned Depth) const {
|
|
assert((Op.getOpcode() >= ISD::BUILTIN_OP_END ||
|
|
Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN ||
|
|
Op.getOpcode() == ISD::INTRINSIC_W_CHAIN ||
|
|
Op.getOpcode() == ISD::INTRINSIC_VOID) &&
|
|
"Should use MaskedValueIsZero if you don't know whether Op"
|
|
" is a target node!");
|
|
KnownZero = KnownOne = APInt(Mask.getBitWidth(), 0);
|
|
}
|
|
|
|
/// ComputeNumSignBitsForTargetNode - This method can be implemented by
|
|
/// targets that want to expose additional information about sign bits to the
|
|
/// DAG Combiner.
|
|
unsigned TargetLowering::ComputeNumSignBitsForTargetNode(SDOperand Op,
|
|
unsigned Depth) const {
|
|
assert((Op.getOpcode() >= ISD::BUILTIN_OP_END ||
|
|
Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN ||
|
|
Op.getOpcode() == ISD::INTRINSIC_W_CHAIN ||
|
|
Op.getOpcode() == ISD::INTRINSIC_VOID) &&
|
|
"Should use ComputeNumSignBits if you don't know whether Op"
|
|
" is a target node!");
|
|
return 1;
|
|
}
|
|
|
|
|
|
/// SimplifySetCC - Try to simplify a setcc built with the specified operands
|
|
/// and cc. If it is unable to simplify it, return a null SDOperand.
|
|
SDOperand
|
|
TargetLowering::SimplifySetCC(MVT VT, SDOperand N0, SDOperand N1,
|
|
ISD::CondCode Cond, bool foldBooleans,
|
|
DAGCombinerInfo &DCI) const {
|
|
SelectionDAG &DAG = DCI.DAG;
|
|
|
|
// These setcc operations always fold.
|
|
switch (Cond) {
|
|
default: break;
|
|
case ISD::SETFALSE:
|
|
case ISD::SETFALSE2: return DAG.getConstant(0, VT);
|
|
case ISD::SETTRUE:
|
|
case ISD::SETTRUE2: return DAG.getConstant(1, VT);
|
|
}
|
|
|
|
if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.Val)) {
|
|
const APInt &C1 = N1C->getAPIntValue();
|
|
if (isa<ConstantSDNode>(N0.Val)) {
|
|
return DAG.FoldSetCC(VT, N0, N1, Cond);
|
|
} else {
|
|
// If the LHS is '(srl (ctlz x), 5)', the RHS is 0/1, and this is an
|
|
// equality comparison, then we're just comparing whether X itself is
|
|
// zero.
|
|
if (N0.getOpcode() == ISD::SRL && (C1 == 0 || C1 == 1) &&
|
|
N0.getOperand(0).getOpcode() == ISD::CTLZ &&
|
|
N0.getOperand(1).getOpcode() == ISD::Constant) {
|
|
unsigned ShAmt = cast<ConstantSDNode>(N0.getOperand(1))->getValue();
|
|
if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
|
|
ShAmt == Log2_32(N0.getValueType().getSizeInBits())) {
|
|
if ((C1 == 0) == (Cond == ISD::SETEQ)) {
|
|
// (srl (ctlz x), 5) == 0 -> X != 0
|
|
// (srl (ctlz x), 5) != 1 -> X != 0
|
|
Cond = ISD::SETNE;
|
|
} else {
|
|
// (srl (ctlz x), 5) != 0 -> X == 0
|
|
// (srl (ctlz x), 5) == 1 -> X == 0
|
|
Cond = ISD::SETEQ;
|
|
}
|
|
SDOperand Zero = DAG.getConstant(0, N0.getValueType());
|
|
return DAG.getSetCC(VT, N0.getOperand(0).getOperand(0),
|
|
Zero, Cond);
|
|
}
|
|
}
|
|
|
|
// If the LHS is a ZERO_EXTEND, perform the comparison on the input.
|
|
if (N0.getOpcode() == ISD::ZERO_EXTEND) {
|
|
unsigned InSize = N0.getOperand(0).getValueType().getSizeInBits();
|
|
|
|
// If the comparison constant has bits in the upper part, the
|
|
// zero-extended value could never match.
|
|
if (C1.intersects(APInt::getHighBitsSet(C1.getBitWidth(),
|
|
C1.getBitWidth() - InSize))) {
|
|
switch (Cond) {
|
|
case ISD::SETUGT:
|
|
case ISD::SETUGE:
|
|
case ISD::SETEQ: return DAG.getConstant(0, VT);
|
|
case ISD::SETULT:
|
|
case ISD::SETULE:
|
|
case ISD::SETNE: return DAG.getConstant(1, VT);
|
|
case ISD::SETGT:
|
|
case ISD::SETGE:
|
|
// True if the sign bit of C1 is set.
|
|
return DAG.getConstant(C1.isNegative(), VT);
|
|
case ISD::SETLT:
|
|
case ISD::SETLE:
|
|
// True if the sign bit of C1 isn't set.
|
|
return DAG.getConstant(C1.isNonNegative(), VT);
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Otherwise, we can perform the comparison with the low bits.
|
|
switch (Cond) {
|
|
case ISD::SETEQ:
|
|
case ISD::SETNE:
|
|
case ISD::SETUGT:
|
|
case ISD::SETUGE:
|
|
case ISD::SETULT:
|
|
case ISD::SETULE:
|
|
return DAG.getSetCC(VT, N0.getOperand(0),
|
|
DAG.getConstant(APInt(C1).trunc(InSize),
|
|
N0.getOperand(0).getValueType()),
|
|
Cond);
|
|
default:
|
|
break; // todo, be more careful with signed comparisons
|
|
}
|
|
} else if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG &&
|
|
(Cond == ISD::SETEQ || Cond == ISD::SETNE)) {
|
|
MVT ExtSrcTy = cast<VTSDNode>(N0.getOperand(1))->getVT();
|
|
unsigned ExtSrcTyBits = ExtSrcTy.getSizeInBits();
|
|
MVT ExtDstTy = N0.getValueType();
|
|
unsigned ExtDstTyBits = ExtDstTy.getSizeInBits();
|
|
|
|
// If the extended part has any inconsistent bits, it cannot ever
|
|
// compare equal. In other words, they have to be all ones or all
|
|
// zeros.
|
|
APInt ExtBits =
|
|
APInt::getHighBitsSet(ExtDstTyBits, ExtDstTyBits - ExtSrcTyBits);
|
|
if ((C1 & ExtBits) != 0 && (C1 & ExtBits) != ExtBits)
|
|
return DAG.getConstant(Cond == ISD::SETNE, VT);
|
|
|
|
SDOperand ZextOp;
|
|
MVT Op0Ty = N0.getOperand(0).getValueType();
|
|
if (Op0Ty == ExtSrcTy) {
|
|
ZextOp = N0.getOperand(0);
|
|
} else {
|
|
APInt Imm = APInt::getLowBitsSet(ExtDstTyBits, ExtSrcTyBits);
|
|
ZextOp = DAG.getNode(ISD::AND, Op0Ty, N0.getOperand(0),
|
|
DAG.getConstant(Imm, Op0Ty));
|
|
}
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(ZextOp.Val);
|
|
// Otherwise, make this a use of a zext.
|
|
return DAG.getSetCC(VT, ZextOp,
|
|
DAG.getConstant(C1 & APInt::getLowBitsSet(
|
|
ExtDstTyBits,
|
|
ExtSrcTyBits),
|
|
ExtDstTy),
|
|
Cond);
|
|
} else if ((N1C->isNullValue() || N1C->getAPIntValue() == 1) &&
|
|
(Cond == ISD::SETEQ || Cond == ISD::SETNE)) {
|
|
|
|
// SETCC (SETCC), [0|1], [EQ|NE] -> SETCC
|
|
if (N0.getOpcode() == ISD::SETCC) {
|
|
bool TrueWhenTrue = (Cond == ISD::SETEQ) ^ (N1C->getValue() != 1);
|
|
if (TrueWhenTrue)
|
|
return N0;
|
|
|
|
// Invert the condition.
|
|
ISD::CondCode CC = cast<CondCodeSDNode>(N0.getOperand(2))->get();
|
|
CC = ISD::getSetCCInverse(CC,
|
|
N0.getOperand(0).getValueType().isInteger());
|
|
return DAG.getSetCC(VT, N0.getOperand(0), N0.getOperand(1), CC);
|
|
}
|
|
|
|
if ((N0.getOpcode() == ISD::XOR ||
|
|
(N0.getOpcode() == ISD::AND &&
|
|
N0.getOperand(0).getOpcode() == ISD::XOR &&
|
|
N0.getOperand(1) == N0.getOperand(0).getOperand(1))) &&
|
|
isa<ConstantSDNode>(N0.getOperand(1)) &&
|
|
cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue() == 1) {
|
|
// If this is (X^1) == 0/1, swap the RHS and eliminate the xor. We
|
|
// can only do this if the top bits are known zero.
|
|
unsigned BitWidth = N0.getValueSizeInBits();
|
|
if (DAG.MaskedValueIsZero(N0,
|
|
APInt::getHighBitsSet(BitWidth,
|
|
BitWidth-1))) {
|
|
// Okay, get the un-inverted input value.
|
|
SDOperand Val;
|
|
if (N0.getOpcode() == ISD::XOR)
|
|
Val = N0.getOperand(0);
|
|
else {
|
|
assert(N0.getOpcode() == ISD::AND &&
|
|
N0.getOperand(0).getOpcode() == ISD::XOR);
|
|
// ((X^1)&1)^1 -> X & 1
|
|
Val = DAG.getNode(ISD::AND, N0.getValueType(),
|
|
N0.getOperand(0).getOperand(0),
|
|
N0.getOperand(1));
|
|
}
|
|
return DAG.getSetCC(VT, Val, N1,
|
|
Cond == ISD::SETEQ ? ISD::SETNE : ISD::SETEQ);
|
|
}
|
|
}
|
|
}
|
|
|
|
APInt MinVal, MaxVal;
|
|
unsigned OperandBitSize = N1C->getValueType(0).getSizeInBits();
|
|
if (ISD::isSignedIntSetCC(Cond)) {
|
|
MinVal = APInt::getSignedMinValue(OperandBitSize);
|
|
MaxVal = APInt::getSignedMaxValue(OperandBitSize);
|
|
} else {
|
|
MinVal = APInt::getMinValue(OperandBitSize);
|
|
MaxVal = APInt::getMaxValue(OperandBitSize);
|
|
}
|
|
|
|
// Canonicalize GE/LE comparisons to use GT/LT comparisons.
|
|
if (Cond == ISD::SETGE || Cond == ISD::SETUGE) {
|
|
if (C1 == MinVal) return DAG.getConstant(1, VT); // X >= MIN --> true
|
|
// X >= C0 --> X > (C0-1)
|
|
return DAG.getSetCC(VT, N0, DAG.getConstant(C1-1, N1.getValueType()),
|
|
(Cond == ISD::SETGE) ? ISD::SETGT : ISD::SETUGT);
|
|
}
|
|
|
|
if (Cond == ISD::SETLE || Cond == ISD::SETULE) {
|
|
if (C1 == MaxVal) return DAG.getConstant(1, VT); // X <= MAX --> true
|
|
// X <= C0 --> X < (C0+1)
|
|
return DAG.getSetCC(VT, N0, DAG.getConstant(C1+1, N1.getValueType()),
|
|
(Cond == ISD::SETLE) ? ISD::SETLT : ISD::SETULT);
|
|
}
|
|
|
|
if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C1 == MinVal)
|
|
return DAG.getConstant(0, VT); // X < MIN --> false
|
|
if ((Cond == ISD::SETGE || Cond == ISD::SETUGE) && C1 == MinVal)
|
|
return DAG.getConstant(1, VT); // X >= MIN --> true
|
|
if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C1 == MaxVal)
|
|
return DAG.getConstant(0, VT); // X > MAX --> false
|
|
if ((Cond == ISD::SETLE || Cond == ISD::SETULE) && C1 == MaxVal)
|
|
return DAG.getConstant(1, VT); // X <= MAX --> true
|
|
|
|
// Canonicalize setgt X, Min --> setne X, Min
|
|
if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C1 == MinVal)
|
|
return DAG.getSetCC(VT, N0, N1, ISD::SETNE);
|
|
// Canonicalize setlt X, Max --> setne X, Max
|
|
if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C1 == MaxVal)
|
|
return DAG.getSetCC(VT, N0, N1, ISD::SETNE);
|
|
|
|
// If we have setult X, 1, turn it into seteq X, 0
|
|
if ((Cond == ISD::SETLT || Cond == ISD::SETULT) && C1 == MinVal+1)
|
|
return DAG.getSetCC(VT, N0, DAG.getConstant(MinVal, N0.getValueType()),
|
|
ISD::SETEQ);
|
|
// If we have setugt X, Max-1, turn it into seteq X, Max
|
|
else if ((Cond == ISD::SETGT || Cond == ISD::SETUGT) && C1 == MaxVal-1)
|
|
return DAG.getSetCC(VT, N0, DAG.getConstant(MaxVal, N0.getValueType()),
|
|
ISD::SETEQ);
|
|
|
|
// If we have "setcc X, C0", check to see if we can shrink the immediate
|
|
// by changing cc.
|
|
|
|
// SETUGT X, SINTMAX -> SETLT X, 0
|
|
if (Cond == ISD::SETUGT && OperandBitSize != 1 &&
|
|
C1 == (~0ULL >> (65-OperandBitSize)))
|
|
return DAG.getSetCC(VT, N0, DAG.getConstant(0, N1.getValueType()),
|
|
ISD::SETLT);
|
|
|
|
// FIXME: Implement the rest of these.
|
|
|
|
// Fold bit comparisons when we can.
|
|
if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
|
|
VT == N0.getValueType() && N0.getOpcode() == ISD::AND)
|
|
if (ConstantSDNode *AndRHS =
|
|
dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
|
|
if (Cond == ISD::SETNE && C1 == 0) {// (X & 8) != 0 --> (X & 8) >> 3
|
|
// Perform the xform if the AND RHS is a single bit.
|
|
if (isPowerOf2_64(AndRHS->getValue())) {
|
|
return DAG.getNode(ISD::SRL, VT, N0,
|
|
DAG.getConstant(Log2_64(AndRHS->getValue()),
|
|
getShiftAmountTy()));
|
|
}
|
|
} else if (Cond == ISD::SETEQ && C1 == AndRHS->getValue()) {
|
|
// (X & 8) == 8 --> (X & 8) >> 3
|
|
// Perform the xform if C1 is a single bit.
|
|
if (C1.isPowerOf2()) {
|
|
return DAG.getNode(ISD::SRL, VT, N0,
|
|
DAG.getConstant(C1.logBase2(), getShiftAmountTy()));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
} else if (isa<ConstantSDNode>(N0.Val)) {
|
|
// Ensure that the constant occurs on the RHS.
|
|
return DAG.getSetCC(VT, N1, N0, ISD::getSetCCSwappedOperands(Cond));
|
|
}
|
|
|
|
if (isa<ConstantFPSDNode>(N0.Val)) {
|
|
// Constant fold or commute setcc.
|
|
SDOperand O = DAG.FoldSetCC(VT, N0, N1, Cond);
|
|
if (O.Val) return O;
|
|
} else if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N1.Val)) {
|
|
// If the RHS of an FP comparison is a constant, simplify it away in
|
|
// some cases.
|
|
if (CFP->getValueAPF().isNaN()) {
|
|
// If an operand is known to be a nan, we can fold it.
|
|
switch (ISD::getUnorderedFlavor(Cond)) {
|
|
default: assert(0 && "Unknown flavor!");
|
|
case 0: // Known false.
|
|
return DAG.getConstant(0, VT);
|
|
case 1: // Known true.
|
|
return DAG.getConstant(1, VT);
|
|
case 2: // Undefined.
|
|
return DAG.getNode(ISD::UNDEF, VT);
|
|
}
|
|
}
|
|
|
|
// Otherwise, we know the RHS is not a NaN. Simplify the node to drop the
|
|
// constant if knowing that the operand is non-nan is enough. We prefer to
|
|
// have SETO(x,x) instead of SETO(x, 0.0) because this avoids having to
|
|
// materialize 0.0.
|
|
if (Cond == ISD::SETO || Cond == ISD::SETUO)
|
|
return DAG.getSetCC(VT, N0, N0, Cond);
|
|
}
|
|
|
|
if (N0 == N1) {
|
|
// We can always fold X == X for integer setcc's.
|
|
if (N0.getValueType().isInteger())
|
|
return DAG.getConstant(ISD::isTrueWhenEqual(Cond), VT);
|
|
unsigned UOF = ISD::getUnorderedFlavor(Cond);
|
|
if (UOF == 2) // FP operators that are undefined on NaNs.
|
|
return DAG.getConstant(ISD::isTrueWhenEqual(Cond), VT);
|
|
if (UOF == unsigned(ISD::isTrueWhenEqual(Cond)))
|
|
return DAG.getConstant(UOF, VT);
|
|
// Otherwise, we can't fold it. However, we can simplify it to SETUO/SETO
|
|
// if it is not already.
|
|
ISD::CondCode NewCond = UOF == 0 ? ISD::SETO : ISD::SETUO;
|
|
if (NewCond != Cond)
|
|
return DAG.getSetCC(VT, N0, N1, NewCond);
|
|
}
|
|
|
|
if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
|
|
N0.getValueType().isInteger()) {
|
|
if (N0.getOpcode() == ISD::ADD || N0.getOpcode() == ISD::SUB ||
|
|
N0.getOpcode() == ISD::XOR) {
|
|
// Simplify (X+Y) == (X+Z) --> Y == Z
|
|
if (N0.getOpcode() == N1.getOpcode()) {
|
|
if (N0.getOperand(0) == N1.getOperand(0))
|
|
return DAG.getSetCC(VT, N0.getOperand(1), N1.getOperand(1), Cond);
|
|
if (N0.getOperand(1) == N1.getOperand(1))
|
|
return DAG.getSetCC(VT, N0.getOperand(0), N1.getOperand(0), Cond);
|
|
if (DAG.isCommutativeBinOp(N0.getOpcode())) {
|
|
// If X op Y == Y op X, try other combinations.
|
|
if (N0.getOperand(0) == N1.getOperand(1))
|
|
return DAG.getSetCC(VT, N0.getOperand(1), N1.getOperand(0), Cond);
|
|
if (N0.getOperand(1) == N1.getOperand(0))
|
|
return DAG.getSetCC(VT, N0.getOperand(0), N1.getOperand(1), Cond);
|
|
}
|
|
}
|
|
|
|
if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(N1)) {
|
|
if (ConstantSDNode *LHSR = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
|
|
// Turn (X+C1) == C2 --> X == C2-C1
|
|
if (N0.getOpcode() == ISD::ADD && N0.Val->hasOneUse()) {
|
|
return DAG.getSetCC(VT, N0.getOperand(0),
|
|
DAG.getConstant(RHSC->getValue()-LHSR->getValue(),
|
|
N0.getValueType()), Cond);
|
|
}
|
|
|
|
// Turn (X^C1) == C2 into X == C1^C2 iff X&~C1 = 0.
|
|
if (N0.getOpcode() == ISD::XOR)
|
|
// If we know that all of the inverted bits are zero, don't bother
|
|
// performing the inversion.
|
|
if (DAG.MaskedValueIsZero(N0.getOperand(0), ~LHSR->getAPIntValue()))
|
|
return
|
|
DAG.getSetCC(VT, N0.getOperand(0),
|
|
DAG.getConstant(LHSR->getAPIntValue() ^
|
|
RHSC->getAPIntValue(),
|
|
N0.getValueType()),
|
|
Cond);
|
|
}
|
|
|
|
// Turn (C1-X) == C2 --> X == C1-C2
|
|
if (ConstantSDNode *SUBC = dyn_cast<ConstantSDNode>(N0.getOperand(0))) {
|
|
if (N0.getOpcode() == ISD::SUB && N0.Val->hasOneUse()) {
|
|
return
|
|
DAG.getSetCC(VT, N0.getOperand(1),
|
|
DAG.getConstant(SUBC->getAPIntValue() -
|
|
RHSC->getAPIntValue(),
|
|
N0.getValueType()),
|
|
Cond);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Simplify (X+Z) == X --> Z == 0
|
|
if (N0.getOperand(0) == N1)
|
|
return DAG.getSetCC(VT, N0.getOperand(1),
|
|
DAG.getConstant(0, N0.getValueType()), Cond);
|
|
if (N0.getOperand(1) == N1) {
|
|
if (DAG.isCommutativeBinOp(N0.getOpcode()))
|
|
return DAG.getSetCC(VT, N0.getOperand(0),
|
|
DAG.getConstant(0, N0.getValueType()), Cond);
|
|
else if (N0.Val->hasOneUse()) {
|
|
assert(N0.getOpcode() == ISD::SUB && "Unexpected operation!");
|
|
// (Z-X) == X --> Z == X<<1
|
|
SDOperand SH = DAG.getNode(ISD::SHL, N1.getValueType(),
|
|
N1,
|
|
DAG.getConstant(1, getShiftAmountTy()));
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(SH.Val);
|
|
return DAG.getSetCC(VT, N0.getOperand(0), SH, Cond);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (N1.getOpcode() == ISD::ADD || N1.getOpcode() == ISD::SUB ||
|
|
N1.getOpcode() == ISD::XOR) {
|
|
// Simplify X == (X+Z) --> Z == 0
|
|
if (N1.getOperand(0) == N0) {
|
|
return DAG.getSetCC(VT, N1.getOperand(1),
|
|
DAG.getConstant(0, N1.getValueType()), Cond);
|
|
} else if (N1.getOperand(1) == N0) {
|
|
if (DAG.isCommutativeBinOp(N1.getOpcode())) {
|
|
return DAG.getSetCC(VT, N1.getOperand(0),
|
|
DAG.getConstant(0, N1.getValueType()), Cond);
|
|
} else if (N1.Val->hasOneUse()) {
|
|
assert(N1.getOpcode() == ISD::SUB && "Unexpected operation!");
|
|
// X == (Z-X) --> X<<1 == Z
|
|
SDOperand SH = DAG.getNode(ISD::SHL, N1.getValueType(), N0,
|
|
DAG.getConstant(1, getShiftAmountTy()));
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(SH.Val);
|
|
return DAG.getSetCC(VT, SH, N1.getOperand(0), Cond);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Fold away ALL boolean setcc's.
|
|
SDOperand Temp;
|
|
if (N0.getValueType() == MVT::i1 && foldBooleans) {
|
|
switch (Cond) {
|
|
default: assert(0 && "Unknown integer setcc!");
|
|
case ISD::SETEQ: // X == Y -> (X^Y)^1
|
|
Temp = DAG.getNode(ISD::XOR, MVT::i1, N0, N1);
|
|
N0 = DAG.getNode(ISD::XOR, MVT::i1, Temp, DAG.getConstant(1, MVT::i1));
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(Temp.Val);
|
|
break;
|
|
case ISD::SETNE: // X != Y --> (X^Y)
|
|
N0 = DAG.getNode(ISD::XOR, MVT::i1, N0, N1);
|
|
break;
|
|
case ISD::SETGT: // X >s Y --> X == 0 & Y == 1 --> X^1 & Y
|
|
case ISD::SETULT: // X <u Y --> X == 0 & Y == 1 --> X^1 & Y
|
|
Temp = DAG.getNode(ISD::XOR, MVT::i1, N0, DAG.getConstant(1, MVT::i1));
|
|
N0 = DAG.getNode(ISD::AND, MVT::i1, N1, Temp);
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(Temp.Val);
|
|
break;
|
|
case ISD::SETLT: // X <s Y --> X == 1 & Y == 0 --> Y^1 & X
|
|
case ISD::SETUGT: // X >u Y --> X == 1 & Y == 0 --> Y^1 & X
|
|
Temp = DAG.getNode(ISD::XOR, MVT::i1, N1, DAG.getConstant(1, MVT::i1));
|
|
N0 = DAG.getNode(ISD::AND, MVT::i1, N0, Temp);
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(Temp.Val);
|
|
break;
|
|
case ISD::SETULE: // X <=u Y --> X == 0 | Y == 1 --> X^1 | Y
|
|
case ISD::SETGE: // X >=s Y --> X == 0 | Y == 1 --> X^1 | Y
|
|
Temp = DAG.getNode(ISD::XOR, MVT::i1, N0, DAG.getConstant(1, MVT::i1));
|
|
N0 = DAG.getNode(ISD::OR, MVT::i1, N1, Temp);
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(Temp.Val);
|
|
break;
|
|
case ISD::SETUGE: // X >=u Y --> X == 1 | Y == 0 --> Y^1 | X
|
|
case ISD::SETLE: // X <=s Y --> X == 1 | Y == 0 --> Y^1 | X
|
|
Temp = DAG.getNode(ISD::XOR, MVT::i1, N1, DAG.getConstant(1, MVT::i1));
|
|
N0 = DAG.getNode(ISD::OR, MVT::i1, N0, Temp);
|
|
break;
|
|
}
|
|
if (VT != MVT::i1) {
|
|
if (!DCI.isCalledByLegalizer())
|
|
DCI.AddToWorklist(N0.Val);
|
|
// FIXME: If running after legalize, we probably can't do this.
|
|
N0 = DAG.getNode(ISD::ZERO_EXTEND, VT, N0);
|
|
}
|
|
return N0;
|
|
}
|
|
|
|
// Could not fold it.
|
|
return SDOperand();
|
|
}
|
|
|
|
/// isGAPlusOffset - Returns true (and the GlobalValue and the offset) if the
|
|
/// node is a GlobalAddress + offset.
|
|
bool TargetLowering::isGAPlusOffset(SDNode *N, GlobalValue* &GA,
|
|
int64_t &Offset) const {
|
|
if (isa<GlobalAddressSDNode>(N)) {
|
|
GlobalAddressSDNode *GASD = cast<GlobalAddressSDNode>(N);
|
|
GA = GASD->getGlobal();
|
|
Offset += GASD->getOffset();
|
|
return true;
|
|
}
|
|
|
|
if (N->getOpcode() == ISD::ADD) {
|
|
SDOperand N1 = N->getOperand(0);
|
|
SDOperand N2 = N->getOperand(1);
|
|
if (isGAPlusOffset(N1.Val, GA, Offset)) {
|
|
ConstantSDNode *V = dyn_cast<ConstantSDNode>(N2);
|
|
if (V) {
|
|
Offset += V->getSignExtended();
|
|
return true;
|
|
}
|
|
} else if (isGAPlusOffset(N2.Val, GA, Offset)) {
|
|
ConstantSDNode *V = dyn_cast<ConstantSDNode>(N1);
|
|
if (V) {
|
|
Offset += V->getSignExtended();
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
/// isConsecutiveLoad - Return true if LD (which must be a LoadSDNode) is
|
|
/// loading 'Bytes' bytes from a location that is 'Dist' units away from the
|
|
/// location that the 'Base' load is loading from.
|
|
bool TargetLowering::isConsecutiveLoad(SDNode *LD, SDNode *Base,
|
|
unsigned Bytes, int Dist,
|
|
const MachineFrameInfo *MFI) const {
|
|
if (LD->getOperand(0).Val != Base->getOperand(0).Val)
|
|
return false;
|
|
MVT VT = LD->getValueType(0);
|
|
if (VT.getSizeInBits() / 8 != Bytes)
|
|
return false;
|
|
|
|
SDOperand Loc = LD->getOperand(1);
|
|
SDOperand BaseLoc = Base->getOperand(1);
|
|
if (Loc.getOpcode() == ISD::FrameIndex) {
|
|
if (BaseLoc.getOpcode() != ISD::FrameIndex)
|
|
return false;
|
|
int FI = cast<FrameIndexSDNode>(Loc)->getIndex();
|
|
int BFI = cast<FrameIndexSDNode>(BaseLoc)->getIndex();
|
|
int FS = MFI->getObjectSize(FI);
|
|
int BFS = MFI->getObjectSize(BFI);
|
|
if (FS != BFS || FS != (int)Bytes) return false;
|
|
return MFI->getObjectOffset(FI) == (MFI->getObjectOffset(BFI) + Dist*Bytes);
|
|
}
|
|
|
|
GlobalValue *GV1 = NULL;
|
|
GlobalValue *GV2 = NULL;
|
|
int64_t Offset1 = 0;
|
|
int64_t Offset2 = 0;
|
|
bool isGA1 = isGAPlusOffset(Loc.Val, GV1, Offset1);
|
|
bool isGA2 = isGAPlusOffset(BaseLoc.Val, GV2, Offset2);
|
|
if (isGA1 && isGA2 && GV1 == GV2)
|
|
return Offset1 == (Offset2 + Dist*Bytes);
|
|
return false;
|
|
}
|
|
|
|
|
|
SDOperand TargetLowering::
|
|
PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const {
|
|
// Default implementation: no optimization.
|
|
return SDOperand();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Inline Assembler Implementation Methods
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
|
TargetLowering::ConstraintType
|
|
TargetLowering::getConstraintType(const std::string &Constraint) const {
|
|
// FIXME: lots more standard ones to handle.
|
|
if (Constraint.size() == 1) {
|
|
switch (Constraint[0]) {
|
|
default: break;
|
|
case 'r': return C_RegisterClass;
|
|
case 'm': // memory
|
|
case 'o': // offsetable
|
|
case 'V': // not offsetable
|
|
return C_Memory;
|
|
case 'i': // Simple Integer or Relocatable Constant
|
|
case 'n': // Simple Integer
|
|
case 's': // Relocatable Constant
|
|
case 'X': // Allow ANY value.
|
|
case 'I': // Target registers.
|
|
case 'J':
|
|
case 'K':
|
|
case 'L':
|
|
case 'M':
|
|
case 'N':
|
|
case 'O':
|
|
case 'P':
|
|
return C_Other;
|
|
}
|
|
}
|
|
|
|
if (Constraint.size() > 1 && Constraint[0] == '{' &&
|
|
Constraint[Constraint.size()-1] == '}')
|
|
return C_Register;
|
|
return C_Unknown;
|
|
}
|
|
|
|
/// LowerXConstraint - try to replace an X constraint, which matches anything,
|
|
/// with another that has more specific requirements based on the type of the
|
|
/// corresponding operand.
|
|
const char *TargetLowering::LowerXConstraint(MVT ConstraintVT) const{
|
|
if (ConstraintVT.isInteger())
|
|
return "r";
|
|
if (ConstraintVT.isFloatingPoint())
|
|
return "f"; // works for many targets
|
|
return 0;
|
|
}
|
|
|
|
/// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
|
|
/// vector. If it is invalid, don't add anything to Ops.
|
|
void TargetLowering::LowerAsmOperandForConstraint(SDOperand Op,
|
|
char ConstraintLetter,
|
|
std::vector<SDOperand> &Ops,
|
|
SelectionDAG &DAG) const {
|
|
switch (ConstraintLetter) {
|
|
default: break;
|
|
case 'X': // Allows any operand; labels (basic block) use this.
|
|
if (Op.getOpcode() == ISD::BasicBlock) {
|
|
Ops.push_back(Op);
|
|
return;
|
|
}
|
|
// fall through
|
|
case 'i': // Simple Integer or Relocatable Constant
|
|
case 'n': // Simple Integer
|
|
case 's': { // Relocatable Constant
|
|
// These operands are interested in values of the form (GV+C), where C may
|
|
// be folded in as an offset of GV, or it may be explicitly added. Also, it
|
|
// is possible and fine if either GV or C are missing.
|
|
ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op);
|
|
GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(Op);
|
|
|
|
// If we have "(add GV, C)", pull out GV/C
|
|
if (Op.getOpcode() == ISD::ADD) {
|
|
C = dyn_cast<ConstantSDNode>(Op.getOperand(1));
|
|
GA = dyn_cast<GlobalAddressSDNode>(Op.getOperand(0));
|
|
if (C == 0 || GA == 0) {
|
|
C = dyn_cast<ConstantSDNode>(Op.getOperand(0));
|
|
GA = dyn_cast<GlobalAddressSDNode>(Op.getOperand(1));
|
|
}
|
|
if (C == 0 || GA == 0)
|
|
C = 0, GA = 0;
|
|
}
|
|
|
|
// If we find a valid operand, map to the TargetXXX version so that the
|
|
// value itself doesn't get selected.
|
|
if (GA) { // Either &GV or &GV+C
|
|
if (ConstraintLetter != 'n') {
|
|
int64_t Offs = GA->getOffset();
|
|
if (C) Offs += C->getValue();
|
|
Ops.push_back(DAG.getTargetGlobalAddress(GA->getGlobal(),
|
|
Op.getValueType(), Offs));
|
|
return;
|
|
}
|
|
}
|
|
if (C) { // just C, no GV.
|
|
// Simple constants are not allowed for 's'.
|
|
if (ConstraintLetter != 's') {
|
|
Ops.push_back(DAG.getTargetConstant(C->getValue(), Op.getValueType()));
|
|
return;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
std::vector<unsigned> TargetLowering::
|
|
getRegClassForInlineAsmConstraint(const std::string &Constraint,
|
|
MVT VT) const {
|
|
return std::vector<unsigned>();
|
|
}
|
|
|
|
|
|
std::pair<unsigned, const TargetRegisterClass*> TargetLowering::
|
|
getRegForInlineAsmConstraint(const std::string &Constraint,
|
|
MVT VT) const {
|
|
if (Constraint[0] != '{')
|
|
return std::pair<unsigned, const TargetRegisterClass*>(0, 0);
|
|
assert(*(Constraint.end()-1) == '}' && "Not a brace enclosed constraint?");
|
|
|
|
// Remove the braces from around the name.
|
|
std::string RegName(Constraint.begin()+1, Constraint.end()-1);
|
|
|
|
// Figure out which register class contains this reg.
|
|
const TargetRegisterInfo *RI = TM.getRegisterInfo();
|
|
for (TargetRegisterInfo::regclass_iterator RCI = RI->regclass_begin(),
|
|
E = RI->regclass_end(); RCI != E; ++RCI) {
|
|
const TargetRegisterClass *RC = *RCI;
|
|
|
|
// If none of the the value types for this register class are valid, we
|
|
// can't use it. For example, 64-bit reg classes on 32-bit targets.
|
|
bool isLegal = false;
|
|
for (TargetRegisterClass::vt_iterator I = RC->vt_begin(), E = RC->vt_end();
|
|
I != E; ++I) {
|
|
if (isTypeLegal(*I)) {
|
|
isLegal = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!isLegal) continue;
|
|
|
|
for (TargetRegisterClass::iterator I = RC->begin(), E = RC->end();
|
|
I != E; ++I) {
|
|
if (StringsEqualNoCase(RegName, RI->get(*I).AsmName))
|
|
return std::make_pair(*I, RC);
|
|
}
|
|
}
|
|
|
|
return std::pair<unsigned, const TargetRegisterClass*>(0, 0);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Constraint Selection.
|
|
|
|
/// getConstraintGenerality - Return an integer indicating how general CT
|
|
/// is.
|
|
static unsigned getConstraintGenerality(TargetLowering::ConstraintType CT) {
|
|
switch (CT) {
|
|
default: assert(0 && "Unknown constraint type!");
|
|
case TargetLowering::C_Other:
|
|
case TargetLowering::C_Unknown:
|
|
return 0;
|
|
case TargetLowering::C_Register:
|
|
return 1;
|
|
case TargetLowering::C_RegisterClass:
|
|
return 2;
|
|
case TargetLowering::C_Memory:
|
|
return 3;
|
|
}
|
|
}
|
|
|
|
/// ChooseConstraint - If there are multiple different constraints that we
|
|
/// could pick for this operand (e.g. "imr") try to pick the 'best' one.
|
|
/// This is somewhat tricky: constraints fall into four classes:
|
|
/// Other -> immediates and magic values
|
|
/// Register -> one specific register
|
|
/// RegisterClass -> a group of regs
|
|
/// Memory -> memory
|
|
/// Ideally, we would pick the most specific constraint possible: if we have
|
|
/// something that fits into a register, we would pick it. The problem here
|
|
/// is that if we have something that could either be in a register or in
|
|
/// memory that use of the register could cause selection of *other*
|
|
/// operands to fail: they might only succeed if we pick memory. Because of
|
|
/// this the heuristic we use is:
|
|
///
|
|
/// 1) If there is an 'other' constraint, and if the operand is valid for
|
|
/// that constraint, use it. This makes us take advantage of 'i'
|
|
/// constraints when available.
|
|
/// 2) Otherwise, pick the most general constraint present. This prefers
|
|
/// 'm' over 'r', for example.
|
|
///
|
|
static void ChooseConstraint(TargetLowering::AsmOperandInfo &OpInfo,
|
|
const TargetLowering &TLI,
|
|
SDOperand Op, SelectionDAG *DAG) {
|
|
assert(OpInfo.Codes.size() > 1 && "Doesn't have multiple constraint options");
|
|
unsigned BestIdx = 0;
|
|
TargetLowering::ConstraintType BestType = TargetLowering::C_Unknown;
|
|
int BestGenerality = -1;
|
|
|
|
// Loop over the options, keeping track of the most general one.
|
|
for (unsigned i = 0, e = OpInfo.Codes.size(); i != e; ++i) {
|
|
TargetLowering::ConstraintType CType =
|
|
TLI.getConstraintType(OpInfo.Codes[i]);
|
|
|
|
// If this is an 'other' constraint, see if the operand is valid for it.
|
|
// For example, on X86 we might have an 'rI' constraint. If the operand
|
|
// is an integer in the range [0..31] we want to use I (saving a load
|
|
// of a register), otherwise we must use 'r'.
|
|
if (CType == TargetLowering::C_Other && Op.Val) {
|
|
assert(OpInfo.Codes[i].size() == 1 &&
|
|
"Unhandled multi-letter 'other' constraint");
|
|
std::vector<SDOperand> ResultOps;
|
|
TLI.LowerAsmOperandForConstraint(Op, OpInfo.Codes[i][0],
|
|
ResultOps, *DAG);
|
|
if (!ResultOps.empty()) {
|
|
BestType = CType;
|
|
BestIdx = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// This constraint letter is more general than the previous one, use it.
|
|
int Generality = getConstraintGenerality(CType);
|
|
if (Generality > BestGenerality) {
|
|
BestType = CType;
|
|
BestIdx = i;
|
|
BestGenerality = Generality;
|
|
}
|
|
}
|
|
|
|
OpInfo.ConstraintCode = OpInfo.Codes[BestIdx];
|
|
OpInfo.ConstraintType = BestType;
|
|
}
|
|
|
|
/// ComputeConstraintToUse - Determines the constraint code and constraint
|
|
/// type to use for the specific AsmOperandInfo, setting
|
|
/// OpInfo.ConstraintCode and OpInfo.ConstraintType.
|
|
void TargetLowering::ComputeConstraintToUse(AsmOperandInfo &OpInfo,
|
|
SDOperand Op,
|
|
SelectionDAG *DAG) const {
|
|
assert(!OpInfo.Codes.empty() && "Must have at least one constraint");
|
|
|
|
// Single-letter constraints ('r') are very common.
|
|
if (OpInfo.Codes.size() == 1) {
|
|
OpInfo.ConstraintCode = OpInfo.Codes[0];
|
|
OpInfo.ConstraintType = getConstraintType(OpInfo.ConstraintCode);
|
|
} else {
|
|
ChooseConstraint(OpInfo, *this, Op, DAG);
|
|
}
|
|
|
|
// 'X' matches anything.
|
|
if (OpInfo.ConstraintCode == "X" && OpInfo.CallOperandVal) {
|
|
// Labels and constants are handled elsewhere ('X' is the only thing
|
|
// that matches labels).
|
|
if (isa<BasicBlock>(OpInfo.CallOperandVal) ||
|
|
isa<ConstantInt>(OpInfo.CallOperandVal))
|
|
return;
|
|
|
|
// Otherwise, try to resolve it to something we know about by looking at
|
|
// the actual operand type.
|
|
if (const char *Repl = LowerXConstraint(OpInfo.ConstraintVT)) {
|
|
OpInfo.ConstraintCode = Repl;
|
|
OpInfo.ConstraintType = getConstraintType(OpInfo.ConstraintCode);
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Loop Strength Reduction hooks
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// isLegalAddressingMode - Return true if the addressing mode represented
|
|
/// by AM is legal for this target, for a load/store of the specified type.
|
|
bool TargetLowering::isLegalAddressingMode(const AddrMode &AM,
|
|
const Type *Ty) const {
|
|
// The default implementation of this implements a conservative RISCy, r+r and
|
|
// r+i addr mode.
|
|
|
|
// Allows a sign-extended 16-bit immediate field.
|
|
if (AM.BaseOffs <= -(1LL << 16) || AM.BaseOffs >= (1LL << 16)-1)
|
|
return false;
|
|
|
|
// No global is ever allowed as a base.
|
|
if (AM.BaseGV)
|
|
return false;
|
|
|
|
// Only support r+r,
|
|
switch (AM.Scale) {
|
|
case 0: // "r+i" or just "i", depending on HasBaseReg.
|
|
break;
|
|
case 1:
|
|
if (AM.HasBaseReg && AM.BaseOffs) // "r+r+i" is not allowed.
|
|
return false;
|
|
// Otherwise we have r+r or r+i.
|
|
break;
|
|
case 2:
|
|
if (AM.HasBaseReg || AM.BaseOffs) // 2*r+r or 2*r+i is not allowed.
|
|
return false;
|
|
// Allow 2*r as r+r.
|
|
break;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
// Magic for divide replacement
|
|
|
|
struct ms {
|
|
int64_t m; // magic number
|
|
int64_t s; // shift amount
|
|
};
|
|
|
|
struct mu {
|
|
uint64_t m; // magic number
|
|
int64_t a; // add indicator
|
|
int64_t s; // shift amount
|
|
};
|
|
|
|
/// magic - calculate the magic numbers required to codegen an integer sdiv as
|
|
/// a sequence of multiply and shifts. Requires that the divisor not be 0, 1,
|
|
/// or -1.
|
|
static ms magic32(int32_t d) {
|
|
int32_t p;
|
|
uint32_t ad, anc, delta, q1, r1, q2, r2, t;
|
|
const uint32_t two31 = 0x80000000U;
|
|
struct ms mag;
|
|
|
|
ad = abs(d);
|
|
t = two31 + ((uint32_t)d >> 31);
|
|
anc = t - 1 - t%ad; // absolute value of nc
|
|
p = 31; // initialize p
|
|
q1 = two31/anc; // initialize q1 = 2p/abs(nc)
|
|
r1 = two31 - q1*anc; // initialize r1 = rem(2p,abs(nc))
|
|
q2 = two31/ad; // initialize q2 = 2p/abs(d)
|
|
r2 = two31 - q2*ad; // initialize r2 = rem(2p,abs(d))
|
|
do {
|
|
p = p + 1;
|
|
q1 = 2*q1; // update q1 = 2p/abs(nc)
|
|
r1 = 2*r1; // update r1 = rem(2p/abs(nc))
|
|
if (r1 >= anc) { // must be unsigned comparison
|
|
q1 = q1 + 1;
|
|
r1 = r1 - anc;
|
|
}
|
|
q2 = 2*q2; // update q2 = 2p/abs(d)
|
|
r2 = 2*r2; // update r2 = rem(2p/abs(d))
|
|
if (r2 >= ad) { // must be unsigned comparison
|
|
q2 = q2 + 1;
|
|
r2 = r2 - ad;
|
|
}
|
|
delta = ad - r2;
|
|
} while (q1 < delta || (q1 == delta && r1 == 0));
|
|
|
|
mag.m = (int32_t)(q2 + 1); // make sure to sign extend
|
|
if (d < 0) mag.m = -mag.m; // resulting magic number
|
|
mag.s = p - 32; // resulting shift
|
|
return mag;
|
|
}
|
|
|
|
/// magicu - calculate the magic numbers required to codegen an integer udiv as
|
|
/// a sequence of multiply, add and shifts. Requires that the divisor not be 0.
|
|
static mu magicu32(uint32_t d) {
|
|
int32_t p;
|
|
uint32_t nc, delta, q1, r1, q2, r2;
|
|
struct mu magu;
|
|
magu.a = 0; // initialize "add" indicator
|
|
nc = - 1 - (-d)%d;
|
|
p = 31; // initialize p
|
|
q1 = 0x80000000/nc; // initialize q1 = 2p/nc
|
|
r1 = 0x80000000 - q1*nc; // initialize r1 = rem(2p,nc)
|
|
q2 = 0x7FFFFFFF/d; // initialize q2 = (2p-1)/d
|
|
r2 = 0x7FFFFFFF - q2*d; // initialize r2 = rem((2p-1),d)
|
|
do {
|
|
p = p + 1;
|
|
if (r1 >= nc - r1 ) {
|
|
q1 = 2*q1 + 1; // update q1
|
|
r1 = 2*r1 - nc; // update r1
|
|
}
|
|
else {
|
|
q1 = 2*q1; // update q1
|
|
r1 = 2*r1; // update r1
|
|
}
|
|
if (r2 + 1 >= d - r2) {
|
|
if (q2 >= 0x7FFFFFFF) magu.a = 1;
|
|
q2 = 2*q2 + 1; // update q2
|
|
r2 = 2*r2 + 1 - d; // update r2
|
|
}
|
|
else {
|
|
if (q2 >= 0x80000000) magu.a = 1;
|
|
q2 = 2*q2; // update q2
|
|
r2 = 2*r2 + 1; // update r2
|
|
}
|
|
delta = d - 1 - r2;
|
|
} while (p < 64 && (q1 < delta || (q1 == delta && r1 == 0)));
|
|
magu.m = q2 + 1; // resulting magic number
|
|
magu.s = p - 32; // resulting shift
|
|
return magu;
|
|
}
|
|
|
|
/// magic - calculate the magic numbers required to codegen an integer sdiv as
|
|
/// a sequence of multiply and shifts. Requires that the divisor not be 0, 1,
|
|
/// or -1.
|
|
static ms magic64(int64_t d) {
|
|
int64_t p;
|
|
uint64_t ad, anc, delta, q1, r1, q2, r2, t;
|
|
const uint64_t two63 = 9223372036854775808ULL; // 2^63
|
|
struct ms mag;
|
|
|
|
ad = d >= 0 ? d : -d;
|
|
t = two63 + ((uint64_t)d >> 63);
|
|
anc = t - 1 - t%ad; // absolute value of nc
|
|
p = 63; // initialize p
|
|
q1 = two63/anc; // initialize q1 = 2p/abs(nc)
|
|
r1 = two63 - q1*anc; // initialize r1 = rem(2p,abs(nc))
|
|
q2 = two63/ad; // initialize q2 = 2p/abs(d)
|
|
r2 = two63 - q2*ad; // initialize r2 = rem(2p,abs(d))
|
|
do {
|
|
p = p + 1;
|
|
q1 = 2*q1; // update q1 = 2p/abs(nc)
|
|
r1 = 2*r1; // update r1 = rem(2p/abs(nc))
|
|
if (r1 >= anc) { // must be unsigned comparison
|
|
q1 = q1 + 1;
|
|
r1 = r1 - anc;
|
|
}
|
|
q2 = 2*q2; // update q2 = 2p/abs(d)
|
|
r2 = 2*r2; // update r2 = rem(2p/abs(d))
|
|
if (r2 >= ad) { // must be unsigned comparison
|
|
q2 = q2 + 1;
|
|
r2 = r2 - ad;
|
|
}
|
|
delta = ad - r2;
|
|
} while (q1 < delta || (q1 == delta && r1 == 0));
|
|
|
|
mag.m = q2 + 1;
|
|
if (d < 0) mag.m = -mag.m; // resulting magic number
|
|
mag.s = p - 64; // resulting shift
|
|
return mag;
|
|
}
|
|
|
|
/// magicu - calculate the magic numbers required to codegen an integer udiv as
|
|
/// a sequence of multiply, add and shifts. Requires that the divisor not be 0.
|
|
static mu magicu64(uint64_t d)
|
|
{
|
|
int64_t p;
|
|
uint64_t nc, delta, q1, r1, q2, r2;
|
|
struct mu magu;
|
|
magu.a = 0; // initialize "add" indicator
|
|
nc = - 1 - (-d)%d;
|
|
p = 63; // initialize p
|
|
q1 = 0x8000000000000000ull/nc; // initialize q1 = 2p/nc
|
|
r1 = 0x8000000000000000ull - q1*nc; // initialize r1 = rem(2p,nc)
|
|
q2 = 0x7FFFFFFFFFFFFFFFull/d; // initialize q2 = (2p-1)/d
|
|
r2 = 0x7FFFFFFFFFFFFFFFull - q2*d; // initialize r2 = rem((2p-1),d)
|
|
do {
|
|
p = p + 1;
|
|
if (r1 >= nc - r1 ) {
|
|
q1 = 2*q1 + 1; // update q1
|
|
r1 = 2*r1 - nc; // update r1
|
|
}
|
|
else {
|
|
q1 = 2*q1; // update q1
|
|
r1 = 2*r1; // update r1
|
|
}
|
|
if (r2 + 1 >= d - r2) {
|
|
if (q2 >= 0x7FFFFFFFFFFFFFFFull) magu.a = 1;
|
|
q2 = 2*q2 + 1; // update q2
|
|
r2 = 2*r2 + 1 - d; // update r2
|
|
}
|
|
else {
|
|
if (q2 >= 0x8000000000000000ull) magu.a = 1;
|
|
q2 = 2*q2; // update q2
|
|
r2 = 2*r2 + 1; // update r2
|
|
}
|
|
delta = d - 1 - r2;
|
|
} while (p < 128 && (q1 < delta || (q1 == delta && r1 == 0)));
|
|
magu.m = q2 + 1; // resulting magic number
|
|
magu.s = p - 64; // resulting shift
|
|
return magu;
|
|
}
|
|
|
|
/// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant,
|
|
/// return a DAG expression to select that will generate the same value by
|
|
/// multiplying by a magic number. See:
|
|
/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
|
|
SDOperand TargetLowering::BuildSDIV(SDNode *N, SelectionDAG &DAG,
|
|
std::vector<SDNode*>* Created) const {
|
|
MVT VT = N->getValueType(0);
|
|
|
|
// Check to see if we can do this.
|
|
if (!isTypeLegal(VT) || (VT != MVT::i32 && VT != MVT::i64))
|
|
return SDOperand(); // BuildSDIV only operates on i32 or i64
|
|
|
|
int64_t d = cast<ConstantSDNode>(N->getOperand(1))->getSignExtended();
|
|
ms magics = (VT == MVT::i32) ? magic32(d) : magic64(d);
|
|
|
|
// Multiply the numerator (operand 0) by the magic value
|
|
SDOperand Q;
|
|
if (isOperationLegal(ISD::MULHS, VT))
|
|
Q = DAG.getNode(ISD::MULHS, VT, N->getOperand(0),
|
|
DAG.getConstant(magics.m, VT));
|
|
else if (isOperationLegal(ISD::SMUL_LOHI, VT))
|
|
Q = SDOperand(DAG.getNode(ISD::SMUL_LOHI, DAG.getVTList(VT, VT),
|
|
N->getOperand(0),
|
|
DAG.getConstant(magics.m, VT)).Val, 1);
|
|
else
|
|
return SDOperand(); // No mulhs or equvialent
|
|
// If d > 0 and m < 0, add the numerator
|
|
if (d > 0 && magics.m < 0) {
|
|
Q = DAG.getNode(ISD::ADD, VT, Q, N->getOperand(0));
|
|
if (Created)
|
|
Created->push_back(Q.Val);
|
|
}
|
|
// If d < 0 and m > 0, subtract the numerator.
|
|
if (d < 0 && magics.m > 0) {
|
|
Q = DAG.getNode(ISD::SUB, VT, Q, N->getOperand(0));
|
|
if (Created)
|
|
Created->push_back(Q.Val);
|
|
}
|
|
// Shift right algebraic if shift value is nonzero
|
|
if (magics.s > 0) {
|
|
Q = DAG.getNode(ISD::SRA, VT, Q,
|
|
DAG.getConstant(magics.s, getShiftAmountTy()));
|
|
if (Created)
|
|
Created->push_back(Q.Val);
|
|
}
|
|
// Extract the sign bit and add it to the quotient
|
|
SDOperand T =
|
|
DAG.getNode(ISD::SRL, VT, Q, DAG.getConstant(VT.getSizeInBits()-1,
|
|
getShiftAmountTy()));
|
|
if (Created)
|
|
Created->push_back(T.Val);
|
|
return DAG.getNode(ISD::ADD, VT, Q, T);
|
|
}
|
|
|
|
/// BuildUDIVSequence - Given an ISD::UDIV node expressing a divide by constant,
|
|
/// return a DAG expression to select that will generate the same value by
|
|
/// multiplying by a magic number. See:
|
|
/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
|
|
SDOperand TargetLowering::BuildUDIV(SDNode *N, SelectionDAG &DAG,
|
|
std::vector<SDNode*>* Created) const {
|
|
MVT VT = N->getValueType(0);
|
|
|
|
// Check to see if we can do this.
|
|
if (!isTypeLegal(VT) || (VT != MVT::i32 && VT != MVT::i64))
|
|
return SDOperand(); // BuildUDIV only operates on i32 or i64
|
|
|
|
uint64_t d = cast<ConstantSDNode>(N->getOperand(1))->getValue();
|
|
mu magics = (VT == MVT::i32) ? magicu32(d) : magicu64(d);
|
|
|
|
// Multiply the numerator (operand 0) by the magic value
|
|
SDOperand Q;
|
|
if (isOperationLegal(ISD::MULHU, VT))
|
|
Q = DAG.getNode(ISD::MULHU, VT, N->getOperand(0),
|
|
DAG.getConstant(magics.m, VT));
|
|
else if (isOperationLegal(ISD::UMUL_LOHI, VT))
|
|
Q = SDOperand(DAG.getNode(ISD::UMUL_LOHI, DAG.getVTList(VT, VT),
|
|
N->getOperand(0),
|
|
DAG.getConstant(magics.m, VT)).Val, 1);
|
|
else
|
|
return SDOperand(); // No mulhu or equvialent
|
|
if (Created)
|
|
Created->push_back(Q.Val);
|
|
|
|
if (magics.a == 0) {
|
|
return DAG.getNode(ISD::SRL, VT, Q,
|
|
DAG.getConstant(magics.s, getShiftAmountTy()));
|
|
} else {
|
|
SDOperand NPQ = DAG.getNode(ISD::SUB, VT, N->getOperand(0), Q);
|
|
if (Created)
|
|
Created->push_back(NPQ.Val);
|
|
NPQ = DAG.getNode(ISD::SRL, VT, NPQ,
|
|
DAG.getConstant(1, getShiftAmountTy()));
|
|
if (Created)
|
|
Created->push_back(NPQ.Val);
|
|
NPQ = DAG.getNode(ISD::ADD, VT, NPQ, Q);
|
|
if (Created)
|
|
Created->push_back(NPQ.Val);
|
|
return DAG.getNode(ISD::SRL, VT, NPQ,
|
|
DAG.getConstant(magics.s-1, getShiftAmountTy()));
|
|
}
|
|
}
|