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path: root/lib/Transforms/Scalar/SpeculativeExecution.cpp
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Diffstat (limited to 'lib/Transforms/Scalar/SpeculativeExecution.cpp')
-rw-r--r--lib/Transforms/Scalar/SpeculativeExecution.cpp43
1 files changed, 42 insertions, 1 deletions
diff --git a/lib/Transforms/Scalar/SpeculativeExecution.cpp b/lib/Transforms/Scalar/SpeculativeExecution.cpp
index a0fc966cee2c..a7c308b59877 100644
--- a/lib/Transforms/Scalar/SpeculativeExecution.cpp
+++ b/lib/Transforms/Scalar/SpeculativeExecution.cpp
@@ -208,6 +208,47 @@ bool SpeculativeExecutionPass::runOnBasicBlock(BasicBlock &B) {
return false;
}
+static unsigned ComputeSpeculationCost(const Instruction *I,
+ const TargetTransformInfo &TTI) {
+ switch (Operator::getOpcode(I)) {
+ case Instruction::GetElementPtr:
+ case Instruction::Add:
+ case Instruction::Mul:
+ case Instruction::And:
+ case Instruction::Or:
+ case Instruction::Select:
+ case Instruction::Shl:
+ case Instruction::Sub:
+ case Instruction::LShr:
+ case Instruction::AShr:
+ case Instruction::Xor:
+ case Instruction::ZExt:
+ case Instruction::SExt:
+ case Instruction::Call:
+ case Instruction::BitCast:
+ case Instruction::PtrToInt:
+ case Instruction::IntToPtr:
+ case Instruction::AddrSpaceCast:
+ case Instruction::FPToUI:
+ case Instruction::FPToSI:
+ case Instruction::UIToFP:
+ case Instruction::SIToFP:
+ case Instruction::FPExt:
+ case Instruction::FPTrunc:
+ case Instruction::FAdd:
+ case Instruction::FSub:
+ case Instruction::FMul:
+ case Instruction::FDiv:
+ case Instruction::FRem:
+ case Instruction::ICmp:
+ case Instruction::FCmp:
+ return TTI.getUserCost(I);
+
+ default:
+ return UINT_MAX; // Disallow anything not whitelisted.
+ }
+}
+
bool SpeculativeExecutionPass::considerHoistingFromTo(
BasicBlock &FromBlock, BasicBlock &ToBlock) {
SmallSet<const Instruction *, 8> NotHoisted;
@@ -223,7 +264,7 @@ bool SpeculativeExecutionPass::considerHoistingFromTo(
unsigned TotalSpeculationCost = 0;
for (auto& I : FromBlock) {
- const unsigned Cost = TTI->getUserCost(&I);
+ const unsigned Cost = ComputeSpeculationCost(&I, *TTI);
if (Cost != UINT_MAX && isSafeToSpeculativelyExecute(&I) &&
AllPrecedingUsesFromBlockHoisted(&I)) {
TotalSpeculationCost += Cost;