llvm-project/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp

81 lines
2.7 KiB
C++

//===- InferFunctionAttrs.cpp - Infer implicit function attributes --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/IPO/InferFunctionAttrs.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
using namespace llvm;
#define DEBUG_TYPE "inferattrs"
static bool inferAllPrototypeAttributes(Module &M,
const TargetLibraryInfo &TLI) {
bool Changed = false;
for (Function &F : M.functions())
// We only infer things using the prototype and the name; we don't need
// definitions.
if (F.isDeclaration() && !F.hasFnAttribute((Attribute::OptimizeNone)))
Changed |= inferLibFuncAttributes(F, TLI);
return Changed;
}
PreservedAnalyses InferFunctionAttrsPass::run(Module &M,
ModuleAnalysisManager &AM) {
auto &TLI = AM.getResult<TargetLibraryAnalysis>(M);
if (!inferAllPrototypeAttributes(M, TLI))
// If we didn't infer anything, preserve all analyses.
return PreservedAnalyses::all();
// Otherwise, we may have changed fundamental function attributes, so clear
// out all the passes.
return PreservedAnalyses::none();
}
namespace {
struct InferFunctionAttrsLegacyPass : public ModulePass {
static char ID; // Pass identification, replacement for typeid
InferFunctionAttrsLegacyPass() : ModulePass(ID) {
initializeInferFunctionAttrsLegacyPassPass(
*PassRegistry::getPassRegistry());
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<TargetLibraryInfoWrapperPass>();
}
bool runOnModule(Module &M) override {
if (skipModule(M))
return false;
auto &TLI = getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
return inferAllPrototypeAttributes(M, TLI);
}
};
}
char InferFunctionAttrsLegacyPass::ID = 0;
INITIALIZE_PASS_BEGIN(InferFunctionAttrsLegacyPass, "inferattrs",
"Infer set function attributes", false, false)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
INITIALIZE_PASS_END(InferFunctionAttrsLegacyPass, "inferattrs",
"Infer set function attributes", false, false)
Pass *llvm::createInferFunctionAttrsLegacyPass() {
return new InferFunctionAttrsLegacyPass();
}