[GVN,NewGVN] Move patchReplacementInstruction to Utils/Local.h

This function is shared between both implementations. I am not sure if
Utils/Local.h is the best place though.

Reviewers: davide, dberlin, efriedma, xbolva00

Reviewed By: efriedma, xbolva00

Differential Revision: https://reviews.llvm.org/D47337

llvm-svn: 339138
This commit is contained in:
Florian Hahn 2018-08-07 13:27:33 +00:00
parent 462b74cad3
commit 39bbe179aa
4 changed files with 35 additions and 62 deletions

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@ -393,6 +393,10 @@ void combineMetadata(Instruction *K, const Instruction *J, ArrayRef<unsigned> Kn
/// Unknown metadata is removed.
void combineMetadataForCSE(Instruction *K, const Instruction *J);
/// Patch the replacement so that it is not more restrictive than the value
/// being replaced.
void patchReplacementInstruction(Instruction *I, Value *Repl);
// Replace each use of 'From' with 'To', if that use does not belong to basic
// block where 'From' is defined. Returns the number of replacements made.
unsigned replaceNonLocalUsesWith(Instruction *From, Value *To);

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@ -1444,37 +1444,6 @@ bool GVN::processAssumeIntrinsic(IntrinsicInst *IntrinsicI) {
return Changed;
}
static void patchReplacementInstruction(Instruction *I, Value *Repl) {
auto *ReplInst = dyn_cast<Instruction>(Repl);
if (!ReplInst)
return;
// Patch the replacement so that it is not more restrictive than the value
// being replaced.
// Note that if 'I' is a load being replaced by some operation,
// for example, by an arithmetic operation, then andIRFlags()
// would just erase all math flags from the original arithmetic
// operation, which is clearly not wanted and not needed.
if (!isa<LoadInst>(I))
ReplInst->andIRFlags(I);
// FIXME: If both the original and replacement value are part of the
// same control-flow region (meaning that the execution of one
// guarantees the execution of the other), then we can combine the
// noalias scopes here and do better than the general conservative
// answer used in combineMetadata().
// In general, GVN unifies expressions over different control-flow
// regions, and so we need a conservative combination of the noalias
// scopes.
static const unsigned KnownIDs[] = {
LLVMContext::MD_tbaa, LLVMContext::MD_alias_scope,
LLVMContext::MD_noalias, LLVMContext::MD_range,
LLVMContext::MD_fpmath, LLVMContext::MD_invariant_load,
LLVMContext::MD_invariant_group};
combineMetadata(ReplInst, I, KnownIDs);
}
static void patchAndReplaceAllUsesWith(Instruction *I, Value *Repl) {
patchReplacementInstruction(I, Repl);
I->replaceAllUsesWith(Repl);

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@ -3697,37 +3697,6 @@ void NewGVN::convertClassToLoadsAndStores(
}
}
static void patchReplacementInstruction(Instruction *I, Value *Repl) {
auto *ReplInst = dyn_cast<Instruction>(Repl);
if (!ReplInst)
return;
// Patch the replacement so that it is not more restrictive than the value
// being replaced.
// Note that if 'I' is a load being replaced by some operation,
// for example, by an arithmetic operation, then andIRFlags()
// would just erase all math flags from the original arithmetic
// operation, which is clearly not wanted and not needed.
if (!isa<LoadInst>(I))
ReplInst->andIRFlags(I);
// FIXME: If both the original and replacement value are part of the
// same control-flow region (meaning that the execution of one
// guarantees the execution of the other), then we can combine the
// noalias scopes here and do better than the general conservative
// answer used in combineMetadata().
// In general, GVN unifies expressions over different control-flow
// regions, and so we need a conservative combination of the noalias
// scopes.
static const unsigned KnownIDs[] = {
LLVMContext::MD_tbaa, LLVMContext::MD_alias_scope,
LLVMContext::MD_noalias, LLVMContext::MD_range,
LLVMContext::MD_fpmath, LLVMContext::MD_invariant_load,
LLVMContext::MD_invariant_group};
combineMetadata(ReplInst, I, KnownIDs);
}
static void patchAndReplaceAllUsesWith(Instruction *I, Value *Repl) {
patchReplacementInstruction(I, Repl);
I->replaceAllUsesWith(Repl);

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@ -2354,6 +2354,37 @@ void llvm::combineMetadataForCSE(Instruction *K, const Instruction *J) {
combineMetadata(K, J, KnownIDs);
}
void llvm::patchReplacementInstruction(Instruction *I, Value *Repl) {
auto *ReplInst = dyn_cast<Instruction>(Repl);
if (!ReplInst)
return;
// Patch the replacement so that it is not more restrictive than the value
// being replaced.
// Note that if 'I' is a load being replaced by some operation,
// for example, by an arithmetic operation, then andIRFlags()
// would just erase all math flags from the original arithmetic
// operation, which is clearly not wanted and not needed.
if (!isa<LoadInst>(I))
ReplInst->andIRFlags(I);
// FIXME: If both the original and replacement value are part of the
// same control-flow region (meaning that the execution of one
// guarantees the execution of the other), then we can combine the
// noalias scopes here and do better than the general conservative
// answer used in combineMetadata().
// In general, GVN unifies expressions over different control-flow
// regions, and so we need a conservative combination of the noalias
// scopes.
static const unsigned KnownIDs[] = {
LLVMContext::MD_tbaa, LLVMContext::MD_alias_scope,
LLVMContext::MD_noalias, LLVMContext::MD_range,
LLVMContext::MD_fpmath, LLVMContext::MD_invariant_load,
LLVMContext::MD_invariant_group};
combineMetadata(ReplInst, I, KnownIDs);
}
template <typename RootType, typename DominatesFn>
static unsigned replaceDominatedUsesWith(Value *From, Value *To,
const RootType &Root,