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authorDerek Schuff <dschuff@chromium.org>2013-01-30 11:34:40 -0800
committerDerek Schuff <dschuff@chromium.org>2013-01-30 11:34:40 -0800
commit1843e19bce9b11fc840858e136c6c52cf8b42e0b (patch)
treee8bfc928152e2d3b3dd120d141d13dc08a9b49e4 /lib/Analysis/CostModel.cpp
parentaa0fa8a8df25807f784ec9ca9deeb40328636595 (diff)
parenta662a9862501fc86904e90054f7c1519101d9126 (diff)
Merge commit 'a662a9862501fc86904e90054f7c1519101d9126'
Conflicts: include/llvm/CodeGen/IntrinsicLowering.h include/llvm/MC/MCAssembler.h include/llvm/MC/MCObjectStreamer.h lib/LLVMBuild.txt lib/Linker/LinkArchives.cpp lib/MC/MCAssembler.cpp lib/MC/MCELFStreamer.cpp lib/MC/MCParser/AsmParser.cpp lib/MC/MCPureStreamer.cpp lib/MC/WinCOFFStreamer.cpp lib/Makefile lib/Support/Unix/Memory.inc lib/Support/Unix/Process.inc lib/Support/Unix/Program.inc lib/Target/ARM/ARM.h lib/Target/ARM/ARMFastISel.cpp lib/Target/ARM/ARMISelLowering.cpp lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp lib/Target/Mips/MipsInstrFPU.td lib/Target/X86/CMakeLists.txt lib/Target/X86/X86ISelLowering.cpp lib/Target/X86/X86TargetMachine.cpp lib/Target/X86/X86TargetObjectFile.cpp lib/Transforms/InstCombine/InstCombineCalls.cpp test/CodeGen/X86/fast-isel-x86-64.ll tools/llc/llc.cpp tools/lto/LTOModule.cpp utils/TableGen/EDEmitter.cpp
Diffstat (limited to 'lib/Analysis/CostModel.cpp')
-rw-r--r--lib/Analysis/CostModel.cpp52
1 files changed, 25 insertions, 27 deletions
diff --git a/lib/Analysis/CostModel.cpp b/lib/Analysis/CostModel.cpp
index 0d0a8933b3..1784512bce 100644
--- a/lib/Analysis/CostModel.cpp
+++ b/lib/Analysis/CostModel.cpp
@@ -8,22 +8,25 @@
//===----------------------------------------------------------------------===//
//
// This file defines the cost model analysis. It provides a very basic cost
-// estimation for LLVM-IR. The cost result can be thought of as cycles, but it
-// is really unit-less. The estimated cost is ment to be used for comparing
-// alternatives.
+// estimation for LLVM-IR. This analysis uses the services of the codegen
+// to approximate the cost of any IR instruction when lowered to machine
+// instructions. The cost results are unit-less and the cost number represents
+// the throughput of the machine assuming that all loads hit the cache, all
+// branches are predicted, etc. The cost numbers can be added in order to
+// compare two or more transformation alternatives.
//
//===----------------------------------------------------------------------===//
#define CM_NAME "cost-model"
#define DEBUG_TYPE CM_NAME
#include "llvm/Analysis/Passes.h"
-#include "llvm/Function.h"
-#include "llvm/Instructions.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Value.h"
#include "llvm/Pass.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/TargetTransformInfo.h"
-#include "llvm/Value.h"
using namespace llvm;
namespace {
@@ -31,7 +34,7 @@ namespace {
public:
static char ID; // Class identification, replacement for typeinfo
- CostModelAnalysis() : FunctionPass(ID), F(0), VTTI(0) {
+ CostModelAnalysis() : FunctionPass(ID), F(0), TTI(0) {
initializeCostModelAnalysisPass(
*PassRegistry::getPassRegistry());
}
@@ -49,8 +52,8 @@ namespace {
/// The function that we analyze.
Function *F;
- /// Vector target information.
- const VectorTargetTransformInfo *VTTI;
+ /// Target information.
+ const TargetTransformInfo *TTI;
};
} // End of anonymous namespace
@@ -72,25 +75,20 @@ CostModelAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
bool
CostModelAnalysis::runOnFunction(Function &F) {
this->F = &F;
-
- // Target information.
- TargetTransformInfo *TTI;
TTI = getAnalysisIfAvailable<TargetTransformInfo>();
- if (TTI)
- VTTI = TTI->getVectorTargetTransformInfo();
return false;
}
unsigned CostModelAnalysis::getInstructionCost(const Instruction *I) const {
- if (!VTTI)
+ if (!TTI)
return -1;
switch (I->getOpcode()) {
case Instruction::Ret:
case Instruction::PHI:
case Instruction::Br: {
- return VTTI->getCFInstrCost(I->getOpcode());
+ return TTI->getCFInstrCost(I->getOpcode());
}
case Instruction::Add:
case Instruction::FAdd:
@@ -110,28 +108,28 @@ unsigned CostModelAnalysis::getInstructionCost(const Instruction *I) const {
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
- return VTTI->getArithmeticInstrCost(I->getOpcode(), I->getType());
+ return TTI->getArithmeticInstrCost(I->getOpcode(), I->getType());
}
case Instruction::Select: {
const SelectInst *SI = cast<SelectInst>(I);
Type *CondTy = SI->getCondition()->getType();
- return VTTI->getCmpSelInstrCost(I->getOpcode(), I->getType(), CondTy);
+ return TTI->getCmpSelInstrCost(I->getOpcode(), I->getType(), CondTy);
}
case Instruction::ICmp:
case Instruction::FCmp: {
Type *ValTy = I->getOperand(0)->getType();
- return VTTI->getCmpSelInstrCost(I->getOpcode(), ValTy);
+ return TTI->getCmpSelInstrCost(I->getOpcode(), ValTy);
}
case Instruction::Store: {
const StoreInst *SI = cast<StoreInst>(I);
Type *ValTy = SI->getValueOperand()->getType();
- return VTTI->getMemoryOpCost(I->getOpcode(), ValTy,
+ return TTI->getMemoryOpCost(I->getOpcode(), ValTy,
SI->getAlignment(),
SI->getPointerAddressSpace());
}
case Instruction::Load: {
const LoadInst *LI = cast<LoadInst>(I);
- return VTTI->getMemoryOpCost(I->getOpcode(), I->getType(),
+ return TTI->getMemoryOpCost(I->getOpcode(), I->getType(),
LI->getAlignment(),
LI->getPointerAddressSpace());
}
@@ -148,7 +146,7 @@ unsigned CostModelAnalysis::getInstructionCost(const Instruction *I) const {
case Instruction::FPTrunc:
case Instruction::BitCast: {
Type *SrcTy = I->getOperand(0)->getType();
- return VTTI->getCastInstrCost(I->getOpcode(), I->getType(), SrcTy);
+ return TTI->getCastInstrCost(I->getOpcode(), I->getType(), SrcTy);
}
case Instruction::ExtractElement: {
const ExtractElementInst * EEI = cast<ExtractElementInst>(I);
@@ -156,8 +154,8 @@ unsigned CostModelAnalysis::getInstructionCost(const Instruction *I) const {
unsigned Idx = -1;
if (CI)
Idx = CI->getZExtValue();
- return VTTI->getVectorInstrCost(I->getOpcode(),
- EEI->getOperand(0)->getType(), Idx);
+ return TTI->getVectorInstrCost(I->getOpcode(),
+ EEI->getOperand(0)->getType(), Idx);
}
case Instruction::InsertElement: {
const InsertElementInst * IE = cast<InsertElementInst>(I);
@@ -165,8 +163,8 @@ unsigned CostModelAnalysis::getInstructionCost(const Instruction *I) const {
unsigned Idx = -1;
if (CI)
Idx = CI->getZExtValue();
- return VTTI->getVectorInstrCost(I->getOpcode(),
- IE->getType(), Idx);
+ return TTI->getVectorInstrCost(I->getOpcode(),
+ IE->getType(), Idx);
}
default:
// We don't have any information on this instruction.