summaryrefslogtreecommitdiffstats
path: root/llvm/lib
diff options
context:
space:
mode:
Diffstat (limited to 'llvm/lib')
-rw-r--r--llvm/lib/Transforms/Scalar/LICM.cpp25
1 files changed, 17 insertions, 8 deletions
diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp
index 353a91fe853..6659c5ad1c2 100644
--- a/llvm/lib/Transforms/Scalar/LICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LICM.cpp
@@ -101,7 +101,7 @@ CloneInstructionInExitBlock(Instruction &I, BasicBlock &ExitBlock, PHINode &PN,
const LoopInfo *LI,
const LoopSafetyInfo *SafetyInfo);
static bool canSinkOrHoistInst(Instruction &I, AliasAnalysis *AA,
- DominatorTree *DT, TargetLibraryInfo *TLI,
+ DominatorTree *DT,
Loop *CurLoop, AliasSetTracker *CurAST,
LoopSafetyInfo *SafetyInfo);
@@ -337,7 +337,7 @@ bool llvm::sinkRegion(DomTreeNode *N, AliasAnalysis *AA, LoopInfo *LI,
// operands of the instruction are loop invariant.
//
if (isNotUsedInLoop(I, CurLoop, SafetyInfo) &&
- canSinkOrHoistInst(I, AA, DT, TLI, CurLoop, CurAST, SafetyInfo)) {
+ canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, SafetyInfo)) {
++II;
Changed |= sink(I, LI, DT, CurLoop, CurAST, SafetyInfo);
}
@@ -390,7 +390,7 @@ bool llvm::hoistRegion(DomTreeNode *N, AliasAnalysis *AA, LoopInfo *LI,
// is safe to hoist the instruction.
//
if (CurLoop->hasLoopInvariantOperands(&I) &&
- canSinkOrHoistInst(I, AA, DT, TLI, CurLoop, CurAST, SafetyInfo) &&
+ canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, SafetyInfo) &&
isSafeToExecuteUnconditionally(
I, DT, CurLoop, SafetyInfo,
CurLoop->getLoopPreheader()->getTerminator()))
@@ -436,12 +436,16 @@ void llvm::computeLoopSafetyInfo(LoopSafetyInfo *SafetyInfo, Loop *CurLoop) {
SafetyInfo->BlockColors = colorEHFunclets(*Fn);
}
-/// canSinkOrHoistInst - Return true if the hoister and sinker can handle this
-/// instruction.
+/// Returns true if the hoister and sinker can handle this instruction.
+/// If SafetyInfo is nullptr, we are checking for sinking instructions from
+/// preheader to loop body (no speculation).
+/// If SafetyInfo is not nullptr, we are checking for hoisting/sinking
+/// instructions from loop body to preheader/exit. Check if the instruction
+/// can execute specultatively.
///
-bool canSinkOrHoistInst(Instruction &I, AliasAnalysis *AA, DominatorTree *DT,
- TargetLibraryInfo *TLI, Loop *CurLoop,
- AliasSetTracker *CurAST, LoopSafetyInfo *SafetyInfo) {
+bool canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT,
+ Loop *CurLoop, AliasSetTracker *CurAST,
+ LoopSafetyInfo *SafetyInfo) {
// Loads have extra constraints we have to verify before we can hoist them.
if (LoadInst *LI = dyn_cast<LoadInst>(&I)) {
if (!LI->isUnordered())
@@ -515,6 +519,11 @@ bool canSinkOrHoistInst(Instruction &I, AliasAnalysis *AA, DominatorTree *DT,
!isa<InsertValueInst>(I))
return false;
+ // SafetyInfo is nullptr if we are checking for sinking from preheader to
+ // loop body. It will be always safe as there is no speculative execution.
+ if (!SafetyInfo)
+ return true;
+
// TODO: Plumb the context instruction through to make hoisting and sinking
// more powerful. Hoisting of loads already works due to the special casing
// above.
OpenPOWER on IntegriCloud