llvm-6502/lib/Target/X86/X86TargetAsmInfo.cpp
2008-05-05 16:11:31 +00:00

379 lines
14 KiB
C++

//===-- X86TargetAsmInfo.cpp - X86 asm properties ---------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declarations of the X86TargetAsmInfo properties.
//
//===----------------------------------------------------------------------===//
#include "X86TargetAsmInfo.h"
#include "X86TargetMachine.h"
#include "X86Subtarget.h"
#include "llvm/DerivedTypes.h"
#include "llvm/InlineAsm.h"
#include "llvm/Instructions.h"
#include "llvm/Intrinsics.h"
#include "llvm/Module.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/Dwarf.h"
using namespace llvm;
using namespace llvm::dwarf;
static const char *const x86_asm_table[] = {
"{si}", "S",
"{di}", "D",
"{ax}", "a",
"{cx}", "c",
"{memory}", "memory",
"{flags}", "",
"{dirflag}", "",
"{fpsr}", "",
"{cc}", "cc",
0,0};
X86TargetAsmInfo::X86TargetAsmInfo(const X86TargetMachine &TM) {
const X86Subtarget *Subtarget = &TM.getSubtarget<X86Subtarget>();
X86TM = &TM;
// FIXME - Should be simplified.
AsmTransCBE = x86_asm_table;
switch (Subtarget->TargetType) {
case X86Subtarget::isDarwin:
AlignmentIsInBytes = false;
TextAlignFillValue = 0x90;
GlobalPrefix = "_";
if (!Subtarget->is64Bit())
Data64bitsDirective = 0; // we can't emit a 64-bit unit
ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
PrivateGlobalPrefix = "L"; // Marker for constant pool idxs
BSSSection = 0; // no BSS section.
ZeroFillDirective = "\t.zerofill\t"; // Uses .zerofill
ConstantPoolSection = "\t.const\n";
JumpTableDataSection = "\t.const\n";
CStringSection = "\t.cstring";
FourByteConstantSection = "\t.literal4\n";
EightByteConstantSection = "\t.literal8\n";
if (Subtarget->is64Bit())
SixteenByteConstantSection = "\t.literal16\n";
ReadOnlySection = "\t.const\n";
LCOMMDirective = "\t.lcomm\t";
SwitchToSectionDirective = "\t.section ";
COMMDirectiveTakesAlignment = false;
HasDotTypeDotSizeDirective = false;
if (TM.getRelocationModel() == Reloc::Static) {
StaticCtorsSection = ".constructor";
StaticDtorsSection = ".destructor";
} else {
StaticCtorsSection = ".mod_init_func";
StaticDtorsSection = ".mod_term_func";
}
if (Subtarget->is64Bit()) {
PersonalityPrefix = "";
PersonalitySuffix = "+4@GOTPCREL";
} else {
PersonalityPrefix = "L";
PersonalitySuffix = "$non_lazy_ptr";
}
NeedsIndirectEncoding = true;
InlineAsmStart = "## InlineAsm Start";
InlineAsmEnd = "## InlineAsm End";
CommentString = "##";
SetDirective = "\t.set";
PCSymbol = ".";
UsedDirective = "\t.no_dead_strip\t";
WeakDefDirective = "\t.weak_definition ";
WeakRefDirective = "\t.weak_reference ";
HiddenDirective = "\t.private_extern ";
ProtectedDirective = "\t.globl\t";
// In non-PIC modes, emit a special label before jump tables so that the
// linker can perform more accurate dead code stripping.
if (TM.getRelocationModel() != Reloc::PIC_) {
// Emit a local label that is preserved until the linker runs.
JumpTableSpecialLabelPrefix = "l";
}
SupportsDebugInformation = true;
NeedsSet = true;
DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
// Exceptions handling
SupportsExceptionHandling = true;
GlobalEHDirective = "\t.globl\t";
SupportsWeakOmittedEHFrame = false;
AbsoluteEHSectionOffsets = false;
if (Subtarget->is64Bit())
ShortenEHDataOn64Bit = true;
DwarfEHFrameSection =
".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
DwarfExceptionSection = ".section __DATA,__gcc_except_tab";
break;
case X86Subtarget::isELF:
ReadOnlySection = "\t.section\t.rodata";
FourByteConstantSection = "\t.section\t.rodata.cst4,\"aM\",@progbits,4";
EightByteConstantSection = "\t.section\t.rodata.cst8,\"aM\",@progbits,8";
SixteenByteConstantSection = "\t.section\t.rodata.cst16,\"aM\",@progbits,16";
CStringSection = "\t.section\t.rodata.str1.1,\"aMS\",@progbits,1";
PrivateGlobalPrefix = ".L";
WeakRefDirective = "\t.weak\t";
SetDirective = "\t.set\t";
PCSymbol = ".";
// Set up DWARF directives
HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
// Debug Information
AbsoluteDebugSectionOffsets = true;
SupportsDebugInformation = true;
DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"\",@progbits";
DwarfInfoSection = "\t.section\t.debug_info,\"\",@progbits";
DwarfLineSection = "\t.section\t.debug_line,\"\",@progbits";
DwarfFrameSection = "\t.section\t.debug_frame,\"\",@progbits";
DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",@progbits";
DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",@progbits";
DwarfStrSection = "\t.section\t.debug_str,\"\",@progbits";
DwarfLocSection = "\t.section\t.debug_loc,\"\",@progbits";
DwarfARangesSection = "\t.section\t.debug_aranges,\"\",@progbits";
DwarfRangesSection = "\t.section\t.debug_ranges,\"\",@progbits";
DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",@progbits";
// Exceptions handling
if (!Subtarget->is64Bit())
SupportsExceptionHandling = true;
AbsoluteEHSectionOffsets = false;
DwarfEHFrameSection = "\t.section\t.eh_frame,\"aw\",@progbits";
DwarfExceptionSection = "\t.section\t.gcc_except_table,\"a\",@progbits";
break;
case X86Subtarget::isCygwin:
case X86Subtarget::isMingw:
GlobalPrefix = "_";
LCOMMDirective = "\t.lcomm\t";
COMMDirectiveTakesAlignment = false;
HasDotTypeDotSizeDirective = false;
StaticCtorsSection = "\t.section .ctors,\"aw\"";
StaticDtorsSection = "\t.section .dtors,\"aw\"";
HiddenDirective = NULL;
PrivateGlobalPrefix = "L"; // Prefix for private global symbols
WeakRefDirective = "\t.weak\t";
SetDirective = "\t.set\t";
// Set up DWARF directives
HasLEB128 = true; // Target asm supports leb128 directives (little-endian)
AbsoluteDebugSectionOffsets = true;
AbsoluteEHSectionOffsets = false;
SupportsDebugInformation = true;
DwarfSectionOffsetDirective = "\t.secrel32\t";
DwarfAbbrevSection = "\t.section\t.debug_abbrev,\"dr\"";
DwarfInfoSection = "\t.section\t.debug_info,\"dr\"";
DwarfLineSection = "\t.section\t.debug_line,\"dr\"";
DwarfFrameSection = "\t.section\t.debug_frame,\"dr\"";
DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"dr\"";
DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"dr\"";
DwarfStrSection = "\t.section\t.debug_str,\"dr\"";
DwarfLocSection = "\t.section\t.debug_loc,\"dr\"";
DwarfARangesSection = "\t.section\t.debug_aranges,\"dr\"";
DwarfRangesSection = "\t.section\t.debug_ranges,\"dr\"";
DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"dr\"";
break;
case X86Subtarget::isWindows:
GlobalPrefix = "_";
HasDotTypeDotSizeDirective = false;
break;
default: break;
}
if (Subtarget->isFlavorIntel()) {
GlobalPrefix = "_";
CommentString = ";";
PrivateGlobalPrefix = "$";
AlignDirective = "\talign\t";
ZeroDirective = "\tdb\t";
ZeroDirectiveSuffix = " dup(0)";
AsciiDirective = "\tdb\t";
AscizDirective = 0;
Data8bitsDirective = "\tdb\t";
Data16bitsDirective = "\tdw\t";
Data32bitsDirective = "\tdd\t";
Data64bitsDirective = "\tdq\t";
HasDotTypeDotSizeDirective = false;
TextSection = "_text";
DataSection = "_data";
JumpTableDataSection = NULL;
SwitchToSectionDirective = "";
TextSectionStartSuffix = "\tsegment 'CODE'";
DataSectionStartSuffix = "\tsegment 'DATA'";
SectionEndDirectiveSuffix = "\tends\n";
}
// On Linux we must declare when we can use a non-executable stack.
if (Subtarget->isLinux())
NonexecutableStackDirective = "\t.section\t.note.GNU-stack,\"\",@progbits";
AssemblerDialect = Subtarget->getAsmFlavor();
}
bool X86TargetAsmInfo::LowerToBSwap(CallInst *CI) const {
// FIXME: this should verify that we are targetting a 486 or better. If not,
// we will turn this bswap into something that will be lowered to logical ops
// instead of emitting the bswap asm. For now, we don't support 486 or lower
// so don't worry about this.
// Verify this is a simple bswap.
if (CI->getNumOperands() != 2 ||
CI->getType() != CI->getOperand(1)->getType() ||
!CI->getType()->isInteger())
return false;
const IntegerType *Ty = dyn_cast<IntegerType>(CI->getType());
if (!Ty || Ty->getBitWidth() % 16 != 0)
return false;
// Okay, we can do this xform, do so now.
const Type *Tys[] = { Ty };
Module *M = CI->getParent()->getParent()->getParent();
Constant *Int = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
Value *Op = CI->getOperand(1);
Op = CallInst::Create(Int, Op, CI->getName(), CI);
CI->replaceAllUsesWith(Op);
CI->eraseFromParent();
return true;
}
bool X86TargetAsmInfo::ExpandInlineAsm(CallInst *CI) const {
InlineAsm *IA = cast<InlineAsm>(CI->getCalledValue());
std::vector<InlineAsm::ConstraintInfo> Constraints = IA->ParseConstraints();
std::string AsmStr = IA->getAsmString();
// TODO: should remove alternatives from the asmstring: "foo {a|b}" -> "foo a"
std::vector<std::string> AsmPieces;
SplitString(AsmStr, AsmPieces, "\n"); // ; as separator?
switch (AsmPieces.size()) {
default: return false;
case 1:
AsmStr = AsmPieces[0];
AsmPieces.clear();
SplitString(AsmStr, AsmPieces, " \t"); // Split with whitespace.
// bswap $0
if (AsmPieces.size() == 2 &&
AsmPieces[0] == "bswap" && AsmPieces[1] == "$0") {
// No need to check constraints, nothing other than the equivalent of
// "=r,0" would be valid here.
return LowerToBSwap(CI);
}
break;
case 3:
if (CI->getType() == Type::Int64Ty && Constraints.size() >= 2 &&
Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&
Constraints[1].Codes.size() == 1 && Constraints[1].Codes[0] == "0") {
// bswap %eax / bswap %edx / xchgl %eax, %edx -> llvm.bswap.i64
std::vector<std::string> Words;
SplitString(AsmPieces[0], Words, " \t");
if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%eax") {
Words.clear();
SplitString(AsmPieces[1], Words, " \t");
if (Words.size() == 2 && Words[0] == "bswap" && Words[1] == "%edx") {
Words.clear();
SplitString(AsmPieces[2], Words, " \t,");
if (Words.size() == 3 && Words[0] == "xchgl" && Words[1] == "%eax" &&
Words[2] == "%edx") {
return LowerToBSwap(CI);
}
}
}
}
break;
}
return false;
}
/// PreferredEHDataFormat - This hook allows the target to select data
/// format used for encoding pointers in exception handling data. Reason is
/// 0 for data, 1 for code labels, 2 for function pointers. Global is true
/// if the symbol can be relocated.
unsigned X86TargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
bool Global) const {
const X86Subtarget *Subtarget = &X86TM->getSubtarget<X86Subtarget>();
switch (Subtarget->TargetType) {
case X86Subtarget::isDarwin:
if (Reason == DwarfEncoding::Functions && Global)
return (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4);
else if (Reason == DwarfEncoding::CodeLabels || !Global)
return DW_EH_PE_pcrel;
else
return DW_EH_PE_absptr;
case X86Subtarget::isELF:
case X86Subtarget::isCygwin:
case X86Subtarget::isMingw: {
CodeModel::Model CM = X86TM->getCodeModel();
if (X86TM->getRelocationModel() == Reloc::PIC_) {
unsigned Format = 0;
if (!Subtarget->is64Bit())
// 32 bit targets always encode pointers as 4 bytes
Format = DW_EH_PE_sdata4;
else {
// 64 bit targets encode pointers in 4 bytes iff:
// - code model is small OR
// - code model is medium and we're emitting externally visible symbols or
// any code symbols
if (CM == CodeModel::Small ||
(CM == CodeModel::Medium && (Global ||
Reason != DwarfEncoding::Data)))
Format = DW_EH_PE_sdata4;
else
Format = DW_EH_PE_sdata8;
}
if (Global)
Format |= DW_EH_PE_indirect;
return (Format | DW_EH_PE_pcrel);
} else {
if (Subtarget->is64Bit() &&
(CM == CodeModel::Small ||
(CM == CodeModel::Medium && Reason != DwarfEncoding::Data)))
return DW_EH_PE_udata4;
else
return DW_EH_PE_absptr;
}
}
default:
return TargetAsmInfo::PreferredEHDataFormat(Reason, Global);
}
}