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Do all replacements of __pseudo* memory ops in a single optimization pass.

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Collected the old PseudoGSToGSPass and PseudoMaskedStorePass into a single
pass, ReplacePseudoMemoryOpsPass, which handles both of their tasks.
This commit is contained in:
Matt Pharr
2012-06-12 13:05:03 -07:00
parent 19b46be20d
commit d6c6f95373
1 changed files with 177 additions and 212 deletions
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341
opt.cpp
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@@ -92,10 +92,11 @@ static llvm::Pass *CreateVSelMovmskOptPass();
static llvm::Pass *CreateDetectGSBaseOffsetsPass();
static llvm::Pass *CreateGSToLoadStorePass();
static llvm::Pass *CreateGatherCoalescePass();
static llvm::Pass *CreatePseudoGSToGSPass();
static llvm::Pass *CreatePseudoMaskedStorePass();
static llvm::Pass *CreateMaskedStoreOptPass();
static llvm::Pass *CreateMaskedLoadOptPass();
static llvm::Pass *CreateReplacePseudoMemoryOpsPass();
static llvm::Pass *CreateIsCompileTimeConstantPass(bool isLastTry);
static llvm::Pass *CreateMakeInternalFuncsStaticPass();
@@ -414,10 +415,9 @@ Optimize(llvm::Module *module, int optLevel) {
// take the various __pseudo_* functions it has emitted and turn
// them into something that can actually execute.
optPM.add(CreateDetectGSBaseOffsetsPass());
if (g->opt.disableHandlePseudoMemoryOps == false) {
optPM.add(CreatePseudoGSToGSPass());
optPM.add(CreatePseudoMaskedStorePass());
}
if (g->opt.disableHandlePseudoMemoryOps == false)
optPM.add(CreateReplacePseudoMemoryOpsPass());
optPM.add(CreateIntrinsicsOptPass());
optPM.add(CreateIsCompileTimeConstantPass(true));
optPM.add(llvm::createFunctionInliningPass());
@@ -488,8 +488,7 @@ Optimize(llvm::Module *module, int optLevel) {
optPM.add(CreateMaskedStoreOptPass());
optPM.add(CreateMaskedLoadOptPass());
}
if (g->opt.disableHandlePseudoMemoryOps == false)
optPM.add(CreatePseudoMaskedStorePass());
if (g->opt.disableGatherScatterOptimizations == false &&
g->target.vectorWidth > 1) {
optPM.add(CreateGSToLoadStorePass());
@@ -502,14 +501,15 @@ Optimize(llvm::Module *module, int optLevel) {
optPM.add(CreateGatherCoalescePass());
}
}
if (g->opt.disableHandlePseudoMemoryOps == false) {
optPM.add(CreatePseudoMaskedStorePass());
optPM.add(CreatePseudoGSToGSPass());
}
if (g->opt.disableHandlePseudoMemoryOps == false)
optPM.add(CreateReplacePseudoMemoryOpsPass());
if (!g->opt.disableMaskAllOnOptimizations) {
optPM.add(CreateMaskedStoreOptPass());
optPM.add(CreateMaskedLoadOptPass());
}
optPM.add(llvm::createFunctionInliningPass());
optPM.add(llvm::createConstantPropagationPass());
optPM.add(CreateIntrinsicsOptPass());
@@ -2088,152 +2088,6 @@ CreateMaskedLoadOptPass() {
}
///////////////////////////////////////////////////////////////////////////
// PseudoMaskedStorePass
/** When the front-end needs to do a masked store, it emits a
__pseudo_masked_store* call as a placeholder. This pass lowers these
calls to either __masked_store* or __masked_store_blend* calls.
*/
class PseudoMaskedStorePass : public llvm::BasicBlockPass {
public:
static char ID;
PseudoMaskedStorePass() : BasicBlockPass(ID) { }
const char *getPassName() const { return "Lower Masked Stores"; }
bool runOnBasicBlock(llvm::BasicBlock &BB);
};
char PseudoMaskedStorePass::ID = 0;
/** This routine attempts to determine if the given pointer in lvalue is
pointing to stack-allocated memory. It's conservative in that it
should never return true for non-stack allocated memory, but may return
false for memory that actually is stack allocated. The basic strategy
is to traverse through the operands and see if the pointer originally
comes from an AllocaInst.
*/
static bool
lIsSafeToBlend(llvm::Value *lvalue) {
llvm::BitCastInst *bc = llvm::dyn_cast<llvm::BitCastInst>(lvalue);
if (bc != NULL)
return lIsSafeToBlend(bc->getOperand(0));
else {
llvm::AllocaInst *ai = llvm::dyn_cast<llvm::AllocaInst>(lvalue);
if (ai) {
llvm::Type *type = ai->getType();
llvm::PointerType *pt =
llvm::dyn_cast<llvm::PointerType>(type);
assert(pt != NULL);
type = pt->getElementType();
llvm::ArrayType *at;
while ((at = llvm::dyn_cast<llvm::ArrayType>(type))) {
type = at->getElementType();
}
llvm::VectorType *vt =
llvm::dyn_cast<llvm::VectorType>(type);
return (vt != NULL &&
(int)vt->getNumElements() == g->target.vectorWidth);
}
else {
llvm::GetElementPtrInst *gep =
llvm::dyn_cast<llvm::GetElementPtrInst>(lvalue);
if (gep != NULL)
return lIsSafeToBlend(gep->getOperand(0));
else
return false;
}
}
}
struct LMSInfo {
LMSInfo(const char *pname, const char *bname, const char *msname) {
pseudoFunc = m->module->getFunction(pname);
blendFunc = m->module->getFunction(bname);
maskedStoreFunc = m->module->getFunction(msname);
Assert(pseudoFunc != NULL && blendFunc != NULL &&
maskedStoreFunc != NULL);
}
llvm::Function *pseudoFunc;
llvm::Function *blendFunc;
llvm::Function *maskedStoreFunc;
};
bool
PseudoMaskedStorePass::runOnBasicBlock(llvm::BasicBlock &bb) {
DEBUG_START_PASS("PseudoMaskedStorePass");
LMSInfo msInfo[] = {
LMSInfo("__pseudo_masked_store_i8", "__masked_store_blend_i8",
"__masked_store_i8"),
LMSInfo("__pseudo_masked_store_i16", "__masked_store_blend_i16",
"__masked_store_i16"),
LMSInfo("__pseudo_masked_store_i32", "__masked_store_blend_i32",
"__masked_store_i32"),
LMSInfo("__pseudo_masked_store_float", "__masked_store_blend_float",
"__masked_store_float"),
LMSInfo("__pseudo_masked_store_i64", "__masked_store_blend_i64",
"__masked_store_i64"),
LMSInfo("__pseudo_masked_store_double", "__masked_store_blend_double",
"__masked_store_double")
};
bool modifiedAny = false;
restart:
for (llvm::BasicBlock::iterator iter = bb.begin(), e = bb.end(); iter != e; ++iter) {
// Iterate through all of the instructions and look for
// __pseudo_masked_store_* calls.
llvm::CallInst *callInst = llvm::dyn_cast<llvm::CallInst>(&*iter);
if (callInst == NULL)
continue;
LMSInfo *info = NULL;
for (unsigned int i = 0; i < sizeof(msInfo) / sizeof(msInfo[0]); ++i) {
if (msInfo[i].pseudoFunc != NULL &&
callInst->getCalledFunction() == msInfo[i].pseudoFunc) {
info = &msInfo[i];
break;
}
}
if (info == NULL)
continue;
llvm::Value *lvalue = callInst->getArgOperand(0);
llvm::Value *rvalue = callInst->getArgOperand(1);
llvm::Value *mask = callInst->getArgOperand(2);
// We need to choose between doing the load + blend + store trick,
// or serializing the masked store. Even on targets with a native
// masked store instruction, this is preferable since it lets us
// keep values in registers rather than going out to the stack.
bool doBlend = (!g->opt.disableBlendedMaskedStores &&
lIsSafeToBlend(lvalue));
// Generate the call to the appropriate masked store function and
// replace the __pseudo_* one with it.
llvm::Function *fms = doBlend ? info->blendFunc : info->maskedStoreFunc;
llvm::Instruction *inst = lCallInst(fms, lvalue, rvalue, mask, "", callInst);
lCopyMetadata(inst, callInst);
callInst->eraseFromParent();
modifiedAny = true;
goto restart;
}
DEBUG_END_PASS("PseudoMaskedStorePass");
return modifiedAny;
}
static llvm::Pass *
CreatePseudoMaskedStorePass() {
return new PseudoMaskedStorePass;
}
///////////////////////////////////////////////////////////////////////////
// GSToLoadStorePass
@@ -3595,26 +3449,131 @@ CreateGatherCoalescePass() {
///////////////////////////////////////////////////////////////////////////
// PseudoGSToGSPass
// ReplacePseudoMemoryOpsPass
/** For any gathers and scatters remaining after the GSToLoadStorePass
runs, we need to turn them into actual native gathers and scatters.
This task is handled by the PseudoGSToGSPass here.
This task is handled by the ReplacePseudoMemoryOpsPass here.
*/
class PseudoGSToGSPass : public llvm::BasicBlockPass {
class ReplacePseudoMemoryOpsPass : public llvm::BasicBlockPass {
public:
static char ID;
PseudoGSToGSPass() : BasicBlockPass(ID) { }
ReplacePseudoMemoryOpsPass() : BasicBlockPass(ID) { }
const char *getPassName() const { return "Gather/Scatter Improvements"; }
const char *getPassName() const { return "Replace Pseudo Memory Ops"; }
bool runOnBasicBlock(llvm::BasicBlock &BB);
};
char PseudoGSToGSPass::ID = 0;
char ReplacePseudoMemoryOpsPass::ID = 0;
/** This routine attempts to determine if the given pointer in lvalue is
pointing to stack-allocated memory. It's conservative in that it
should never return true for non-stack allocated memory, but may return
false for memory that actually is stack allocated. The basic strategy
is to traverse through the operands and see if the pointer originally
comes from an AllocaInst.
*/
static bool
lIsSafeToBlend(llvm::Value *lvalue) {
llvm::BitCastInst *bc = llvm::dyn_cast<llvm::BitCastInst>(lvalue);
if (bc != NULL)
return lIsSafeToBlend(bc->getOperand(0));
else {
llvm::AllocaInst *ai = llvm::dyn_cast<llvm::AllocaInst>(lvalue);
if (ai) {
llvm::Type *type = ai->getType();
llvm::PointerType *pt =
llvm::dyn_cast<llvm::PointerType>(type);
assert(pt != NULL);
type = pt->getElementType();
llvm::ArrayType *at;
while ((at = llvm::dyn_cast<llvm::ArrayType>(type))) {
type = at->getElementType();
}
llvm::VectorType *vt =
llvm::dyn_cast<llvm::VectorType>(type);
return (vt != NULL &&
(int)vt->getNumElements() == g->target.vectorWidth);
}
else {
llvm::GetElementPtrInst *gep =
llvm::dyn_cast<llvm::GetElementPtrInst>(lvalue);
if (gep != NULL)
return lIsSafeToBlend(gep->getOperand(0));
else
return false;
}
}
}
struct LowerGSInfo {
static bool
lReplacePseudoMaskedStore(llvm::CallInst *callInst) {
struct LMSInfo {
LMSInfo(const char *pname, const char *bname, const char *msname) {
pseudoFunc = m->module->getFunction(pname);
blendFunc = m->module->getFunction(bname);
maskedStoreFunc = m->module->getFunction(msname);
Assert(pseudoFunc != NULL && blendFunc != NULL &&
maskedStoreFunc != NULL);
}
llvm::Function *pseudoFunc;
llvm::Function *blendFunc;
llvm::Function *maskedStoreFunc;
};
LMSInfo msInfo[] = {
LMSInfo("__pseudo_masked_store_i8", "__masked_store_blend_i8",
"__masked_store_i8"),
LMSInfo("__pseudo_masked_store_i16", "__masked_store_blend_i16",
"__masked_store_i16"),
LMSInfo("__pseudo_masked_store_i32", "__masked_store_blend_i32",
"__masked_store_i32"),
LMSInfo("__pseudo_masked_store_float", "__masked_store_blend_float",
"__masked_store_float"),
LMSInfo("__pseudo_masked_store_i64", "__masked_store_blend_i64",
"__masked_store_i64"),
LMSInfo("__pseudo_masked_store_double", "__masked_store_blend_double",
"__masked_store_double")
};
LMSInfo *info = NULL;
for (unsigned int i = 0; i < sizeof(msInfo) / sizeof(msInfo[0]); ++i) {
if (msInfo[i].pseudoFunc != NULL &&
callInst->getCalledFunction() == msInfo[i].pseudoFunc) {
info = &msInfo[i];
break;
}
}
if (info == NULL)
return false;
llvm::Value *lvalue = callInst->getArgOperand(0);
llvm::Value *rvalue = callInst->getArgOperand(1);
llvm::Value *mask = callInst->getArgOperand(2);
// We need to choose between doing the load + blend + store trick,
// or serializing the masked store. Even on targets with a native
// masked store instruction, this is preferable since it lets us
// keep values in registers rather than going out to the stack.
bool doBlend = (!g->opt.disableBlendedMaskedStores &&
lIsSafeToBlend(lvalue));
// Generate the call to the appropriate masked store function and
// replace the __pseudo_* one with it.
llvm::Function *fms = doBlend ? info->blendFunc : info->maskedStoreFunc;
llvm::Instruction *inst = lCallInst(fms, lvalue, rvalue, mask, "", callInst);
lCopyMetadata(inst, callInst);
callInst->eraseFromParent();
return true;
}
static bool
lReplacePseudoGS(llvm::CallInst *callInst) {
struct LowerGSInfo {
LowerGSInfo(const char *pName, const char *aName, bool ig)
: isGather(ig) {
pseudoFunc = m->module->getFunction(pName);
@@ -3624,12 +3583,7 @@ struct LowerGSInfo {
llvm::Function *pseudoFunc;
llvm::Function *actualFunc;
const bool isGather;
};
bool
PseudoGSToGSPass::runOnBasicBlock(llvm::BasicBlock &bb) {
DEBUG_START_PASS("PseudoGSToGSPass");
};
LowerGSInfo lgsInfo[] = {
LowerGSInfo("__pseudo_gather_base_offsets32_i8", "__gather_base_offsets32_i8", true),
@@ -3689,19 +3643,7 @@ PseudoGSToGSPass::runOnBasicBlock(llvm::BasicBlock &bb) {
LowerGSInfo("__pseudo_scatter64_double", "__scatter64_double", false),
};
bool modifiedAny = false;
restart:
for (llvm::BasicBlock::iterator iter = bb.begin(), e = bb.end(); iter != e; ++iter) {
// Loop over the instructions and find calls to the
// __pseudo_*_base_offsets_* functions.
llvm::CallInst *callInst = llvm::dyn_cast<llvm::CallInst>(&*iter);
if (callInst == NULL)
continue;
llvm::Function *calledFunc = callInst->getCalledFunction();
if (calledFunc == NULL)
continue;
LowerGSInfo *info = NULL;
for (unsigned int i = 0; i < sizeof(lgsInfo) / sizeof(lgsInfo[0]); ++i) {
@@ -3712,7 +3654,8 @@ PseudoGSToGSPass::runOnBasicBlock(llvm::BasicBlock &bb) {
}
}
if (info == NULL)
continue;
return false;
// Get the source position from the metadata attached to the call
// instruction so that we can issue PerformanceWarning()s below.
@@ -3726,19 +3669,42 @@ PseudoGSToGSPass::runOnBasicBlock(llvm::BasicBlock &bb) {
else
PerformanceWarning(pos, "Scatter required to store value.");
}
return true;
}
bool
ReplacePseudoMemoryOpsPass::runOnBasicBlock(llvm::BasicBlock &bb) {
DEBUG_START_PASS("ReplacePseudoMemoryOpsPass");
bool modifiedAny = false;
restart:
for (llvm::BasicBlock::iterator iter = bb.begin(), e = bb.end(); iter != e; ++iter) {
llvm::CallInst *callInst = llvm::dyn_cast<llvm::CallInst>(&*iter);
if (callInst == NULL ||
callInst->getCalledFunction() == NULL)
continue;
if (lReplacePseudoGS(callInst)) {
modifiedAny = true;
goto restart;
}
else if (lReplacePseudoMaskedStore(callInst)) {
modifiedAny = true;
goto restart;
}
}
DEBUG_END_PASS("PseudoGSToGSPass");
DEBUG_END_PASS("ReplacePseudoMemoryOpsPass");
return modifiedAny;
}
static llvm::Pass *
CreatePseudoGSToGSPass() {
return new PseudoGSToGSPass;
CreateReplacePseudoMemoryOpsPass() {
return new ReplacePseudoMemoryOpsPass;
}
@@ -3846,7 +3812,6 @@ CreateIsCompileTimeConstantPass(bool isLastTry) {
return new IsCompileTimeConstantPass(isLastTry);
}
///////////////////////////////////////////////////////////////////////////
// MakeInternalFuncsStaticPass