llvm-6502/lib/Target/X86/X86.td
Preston Gurd 2e2efd9600 Generic Bypass Slow Div
- CodeGenPrepare pass for identifying div/rem ops
- Backend specifies the type mapping using addBypassSlowDivType
- Enabled only for Intel Atom with O2 32-bit -> 8-bit
- Replace IDIV with instructions which test its value and use DIVB if the value
is positive and less than 256.
- In the case when the quotient and remainder of a divide are used a DIV
and a REM instruction will be present in the IR. In the non-Atom case
they are both lowered to IDIVs and CSE removes the redundant IDIV instruction,
using the quotient and remainder from the first IDIV. However,
due to this optimization CSE is not able to eliminate redundant
IDIV instructions because they are located in different basic blocks.
This is overcome by calculating both the quotient (DIV) and remainder (REM)
in each basic block that is inserted by the optimization and reusing the result
values when a subsequent DIV or REM instruction uses the same operands.
- Test cases check for the presents of the optimization when calculating
either the quotient, remainder,  or both.

Patch by Tyler Nowicki!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163150 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-04 18:22:17 +00:00

313 lines
15 KiB
TableGen

//===-- X86.td - Target definition file for the Intel X86 --*- tablegen -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is a target description file for the Intel i386 architecture, referred
// to here as the "X86" architecture.
//
//===----------------------------------------------------------------------===//
// Get the target-independent interfaces which we are implementing...
//
include "llvm/Target/Target.td"
//===----------------------------------------------------------------------===//
// X86 Subtarget state
//
def Mode64Bit : SubtargetFeature<"64bit-mode", "In64BitMode", "true",
"64-bit mode (x86_64)">;
//===----------------------------------------------------------------------===//
// X86 Subtarget features
//===----------------------------------------------------------------------===//
def FeatureCMOV : SubtargetFeature<"cmov","HasCMov", "true",
"Enable conditional move instructions">;
def FeaturePOPCNT : SubtargetFeature<"popcnt", "HasPOPCNT", "true",
"Support POPCNT instruction">;
def FeatureMMX : SubtargetFeature<"mmx","X86SSELevel", "MMX",
"Enable MMX instructions">;
def FeatureSSE1 : SubtargetFeature<"sse", "X86SSELevel", "SSE1",
"Enable SSE instructions",
// SSE codegen depends on cmovs, and all
// SSE1+ processors support them.
[FeatureMMX, FeatureCMOV]>;
def FeatureSSE2 : SubtargetFeature<"sse2", "X86SSELevel", "SSE2",
"Enable SSE2 instructions",
[FeatureSSE1]>;
def FeatureSSE3 : SubtargetFeature<"sse3", "X86SSELevel", "SSE3",
"Enable SSE3 instructions",
[FeatureSSE2]>;
def FeatureSSSE3 : SubtargetFeature<"ssse3", "X86SSELevel", "SSSE3",
"Enable SSSE3 instructions",
[FeatureSSE3]>;
def FeatureSSE41 : SubtargetFeature<"sse41", "X86SSELevel", "SSE41",
"Enable SSE 4.1 instructions",
[FeatureSSSE3]>;
def FeatureSSE42 : SubtargetFeature<"sse42", "X86SSELevel", "SSE42",
"Enable SSE 4.2 instructions",
[FeatureSSE41]>;
def Feature3DNow : SubtargetFeature<"3dnow", "X863DNowLevel", "ThreeDNow",
"Enable 3DNow! instructions",
[FeatureMMX]>;
def Feature3DNowA : SubtargetFeature<"3dnowa", "X863DNowLevel", "ThreeDNowA",
"Enable 3DNow! Athlon instructions",
[Feature3DNow]>;
// All x86-64 hardware has SSE2, but we don't mark SSE2 as an implied
// feature, because SSE2 can be disabled (e.g. for compiling OS kernels)
// without disabling 64-bit mode.
def Feature64Bit : SubtargetFeature<"64bit", "HasX86_64", "true",
"Support 64-bit instructions",
[FeatureCMOV]>;
def FeatureCMPXCHG16B : SubtargetFeature<"cmpxchg16b", "HasCmpxchg16b", "true",
"64-bit with cmpxchg16b",
[Feature64Bit]>;
def FeatureSlowBTMem : SubtargetFeature<"slow-bt-mem", "IsBTMemSlow", "true",
"Bit testing of memory is slow">;
def FeatureFastUAMem : SubtargetFeature<"fast-unaligned-mem",
"IsUAMemFast", "true",
"Fast unaligned memory access">;
def FeatureSSE4A : SubtargetFeature<"sse4a", "HasSSE4A", "true",
"Support SSE 4a instructions",
[FeatureSSE3]>;
def FeatureAVX : SubtargetFeature<"avx", "X86SSELevel", "AVX",
"Enable AVX instructions",
[FeatureSSE42]>;
def FeatureAVX2 : SubtargetFeature<"avx2", "X86SSELevel", "AVX2",
"Enable AVX2 instructions",
[FeatureAVX]>;
def FeaturePCLMUL : SubtargetFeature<"pclmul", "HasPCLMUL", "true",
"Enable packed carry-less multiplication instructions",
[FeatureSSE2]>;
def FeatureFMA : SubtargetFeature<"fma", "HasFMA", "true",
"Enable three-operand fused multiple-add",
[FeatureAVX]>;
def FeatureFMA4 : SubtargetFeature<"fma4", "HasFMA4", "true",
"Enable four-operand fused multiple-add",
[FeatureAVX, FeatureSSE4A]>;
def FeatureXOP : SubtargetFeature<"xop", "HasXOP", "true",
"Enable XOP instructions",
[FeatureFMA4]>;
def FeatureVectorUAMem : SubtargetFeature<"vector-unaligned-mem",
"HasVectorUAMem", "true",
"Allow unaligned memory operands on vector/SIMD instructions">;
def FeatureAES : SubtargetFeature<"aes", "HasAES", "true",
"Enable AES instructions",
[FeatureSSE2]>;
def FeatureMOVBE : SubtargetFeature<"movbe", "HasMOVBE", "true",
"Support MOVBE instruction">;
def FeatureRDRAND : SubtargetFeature<"rdrand", "HasRDRAND", "true",
"Support RDRAND instruction">;
def FeatureF16C : SubtargetFeature<"f16c", "HasF16C", "true",
"Support 16-bit floating point conversion instructions">;
def FeatureFSGSBase : SubtargetFeature<"fsgsbase", "HasFSGSBase", "true",
"Support FS/GS Base instructions">;
def FeatureLZCNT : SubtargetFeature<"lzcnt", "HasLZCNT", "true",
"Support LZCNT instruction">;
def FeatureBMI : SubtargetFeature<"bmi", "HasBMI", "true",
"Support BMI instructions">;
def FeatureBMI2 : SubtargetFeature<"bmi2", "HasBMI2", "true",
"Support BMI2 instructions">;
def FeatureLeaForSP : SubtargetFeature<"lea-sp", "UseLeaForSP", "true",
"Use LEA for adjusting the stack pointer">;
def FeatureSlowDivide : SubtargetFeature<"idiv-to-divb",
"HasSlowDivide", "true",
"Use small divide for positive values less than 256">;
//===----------------------------------------------------------------------===//
// X86 processors supported.
//===----------------------------------------------------------------------===//
include "X86Schedule.td"
def ProcIntelAtom : SubtargetFeature<"atom", "X86ProcFamily", "IntelAtom",
"Intel Atom processors">;
class Proc<string Name, list<SubtargetFeature> Features>
: ProcessorModel<Name, GenericModel, Features>;
class AtomProc<string Name, list<SubtargetFeature> Features>
: ProcessorModel<Name, AtomModel, Features>;
def : Proc<"generic", []>;
def : Proc<"i386", []>;
def : Proc<"i486", []>;
def : Proc<"i586", []>;
def : Proc<"pentium", []>;
def : Proc<"pentium-mmx", [FeatureMMX]>;
def : Proc<"i686", []>;
def : Proc<"pentiumpro", [FeatureCMOV]>;
def : Proc<"pentium2", [FeatureMMX, FeatureCMOV]>;
def : Proc<"pentium3", [FeatureSSE1]>;
def : Proc<"pentium3m", [FeatureSSE1, FeatureSlowBTMem]>;
def : Proc<"pentium-m", [FeatureSSE2, FeatureSlowBTMem]>;
def : Proc<"pentium4", [FeatureSSE2]>;
def : Proc<"pentium4m", [FeatureSSE2, FeatureSlowBTMem]>;
def : Proc<"x86-64", [FeatureSSE2, Feature64Bit, FeatureSlowBTMem]>;
def : Proc<"yonah", [FeatureSSE3, FeatureSlowBTMem]>;
def : Proc<"prescott", [FeatureSSE3, FeatureSlowBTMem]>;
def : Proc<"nocona", [FeatureSSE3, FeatureCMPXCHG16B,
FeatureSlowBTMem]>;
def : Proc<"core2", [FeatureSSSE3, FeatureCMPXCHG16B,
FeatureSlowBTMem]>;
def : Proc<"penryn", [FeatureSSE41, FeatureCMPXCHG16B,
FeatureSlowBTMem]>;
def : AtomProc<"atom", [ProcIntelAtom, FeatureSSE3, FeatureCMPXCHG16B,
FeatureMOVBE, FeatureSlowBTMem, FeatureLeaForSP,
FeatureSlowDivide]>;
// "Arrandale" along with corei3 and corei5
def : Proc<"corei7", [FeatureSSE42, FeatureCMPXCHG16B,
FeatureSlowBTMem, FeatureFastUAMem,
FeaturePOPCNT, FeatureAES]>;
def : Proc<"nehalem", [FeatureSSE42, FeatureCMPXCHG16B,
FeatureSlowBTMem, FeatureFastUAMem,
FeaturePOPCNT]>;
// Westmere is a similar machine to nehalem with some additional features.
// Westmere is the corei3/i5/i7 path from nehalem to sandybridge
def : Proc<"westmere", [FeatureSSE42, FeatureCMPXCHG16B,
FeatureSlowBTMem, FeatureFastUAMem,
FeaturePOPCNT, FeatureAES, FeaturePCLMUL]>;
// Sandy Bridge
// SSE is not listed here since llvm treats AVX as a reimplementation of SSE,
// rather than a superset.
def : Proc<"corei7-avx", [FeatureAVX, FeatureCMPXCHG16B, FeaturePOPCNT,
FeatureAES, FeaturePCLMUL]>;
// Ivy Bridge
def : Proc<"core-avx-i", [FeatureAVX, FeatureCMPXCHG16B, FeaturePOPCNT,
FeatureAES, FeaturePCLMUL,
FeatureRDRAND, FeatureF16C, FeatureFSGSBase]>;
// Haswell
def : Proc<"core-avx2", [FeatureAVX2, FeatureCMPXCHG16B, FeaturePOPCNT,
FeatureAES, FeaturePCLMUL, FeatureRDRAND,
FeatureF16C, FeatureFSGSBase,
FeatureMOVBE, FeatureLZCNT, FeatureBMI,
FeatureBMI2, FeatureFMA]>;
def : Proc<"k6", [FeatureMMX]>;
def : Proc<"k6-2", [Feature3DNow]>;
def : Proc<"k6-3", [Feature3DNow]>;
def : Proc<"athlon", [Feature3DNowA, FeatureSlowBTMem]>;
def : Proc<"athlon-tbird", [Feature3DNowA, FeatureSlowBTMem]>;
def : Proc<"athlon-4", [FeatureSSE1, Feature3DNowA, FeatureSlowBTMem]>;
def : Proc<"athlon-xp", [FeatureSSE1, Feature3DNowA, FeatureSlowBTMem]>;
def : Proc<"athlon-mp", [FeatureSSE1, Feature3DNowA, FeatureSlowBTMem]>;
def : Proc<"k8", [FeatureSSE2, Feature3DNowA, Feature64Bit,
FeatureSlowBTMem]>;
def : Proc<"opteron", [FeatureSSE2, Feature3DNowA, Feature64Bit,
FeatureSlowBTMem]>;
def : Proc<"athlon64", [FeatureSSE2, Feature3DNowA, Feature64Bit,
FeatureSlowBTMem]>;
def : Proc<"athlon-fx", [FeatureSSE2, Feature3DNowA, Feature64Bit,
FeatureSlowBTMem]>;
def : Proc<"k8-sse3", [FeatureSSE3, Feature3DNowA, FeatureCMPXCHG16B,
FeatureSlowBTMem]>;
def : Proc<"opteron-sse3", [FeatureSSE3, Feature3DNowA, FeatureCMPXCHG16B,
FeatureSlowBTMem]>;
def : Proc<"athlon64-sse3", [FeatureSSE3, Feature3DNowA, FeatureCMPXCHG16B,
FeatureSlowBTMem]>;
def : Proc<"amdfam10", [FeatureSSE4A,
Feature3DNowA, FeatureCMPXCHG16B, FeatureLZCNT,
FeaturePOPCNT, FeatureSlowBTMem]>;
// Bobcat
def : Proc<"btver1", [FeatureSSSE3, FeatureSSE4A, FeatureCMPXCHG16B,
FeatureLZCNT, FeaturePOPCNT]>;
// Bulldozer
def : Proc<"bdver1", [FeatureXOP, FeatureFMA4, FeatureCMPXCHG16B,
FeatureAES, FeaturePCLMUL,
FeatureLZCNT, FeaturePOPCNT]>;
// Enhanced Bulldozer
def : Proc<"bdver2", [FeatureXOP, FeatureFMA4, FeatureCMPXCHG16B,
FeatureAES, FeaturePCLMUL,
FeatureF16C, FeatureLZCNT,
FeaturePOPCNT, FeatureBMI, FeatureFMA]>;
def : Proc<"winchip-c6", [FeatureMMX]>;
def : Proc<"winchip2", [Feature3DNow]>;
def : Proc<"c3", [Feature3DNow]>;
def : Proc<"c3-2", [FeatureSSE1]>;
//===----------------------------------------------------------------------===//
// Register File Description
//===----------------------------------------------------------------------===//
include "X86RegisterInfo.td"
//===----------------------------------------------------------------------===//
// Instruction Descriptions
//===----------------------------------------------------------------------===//
include "X86InstrInfo.td"
def X86InstrInfo : InstrInfo;
//===----------------------------------------------------------------------===//
// Calling Conventions
//===----------------------------------------------------------------------===//
include "X86CallingConv.td"
//===----------------------------------------------------------------------===//
// Assembly Parser
//===----------------------------------------------------------------------===//
def ATTAsmParser : AsmParser {
string AsmParserClassName = "AsmParser";
}
def ATTAsmParserVariant : AsmParserVariant {
int Variant = 0;
// Discard comments in assembly strings.
string CommentDelimiter = "#";
// Recognize hard coded registers.
string RegisterPrefix = "%";
}
def IntelAsmParserVariant : AsmParserVariant {
int Variant = 1;
// Discard comments in assembly strings.
string CommentDelimiter = ";";
// Recognize hard coded registers.
string RegisterPrefix = "";
}
//===----------------------------------------------------------------------===//
// Assembly Printers
//===----------------------------------------------------------------------===//
// The X86 target supports two different syntaxes for emitting machine code.
// This is controlled by the -x86-asm-syntax={att|intel}
def ATTAsmWriter : AsmWriter {
string AsmWriterClassName = "ATTInstPrinter";
int Variant = 0;
bit isMCAsmWriter = 1;
}
def IntelAsmWriter : AsmWriter {
string AsmWriterClassName = "IntelInstPrinter";
int Variant = 1;
bit isMCAsmWriter = 1;
}
def X86 : Target {
// Information about the instructions...
let InstructionSet = X86InstrInfo;
let AssemblyParsers = [ATTAsmParser];
let AssemblyParserVariants = [ATTAsmParserVariant, IntelAsmParserVariant];
let AssemblyWriters = [ATTAsmWriter, IntelAsmWriter];
}