blob: 18d5911d10f121910da0492cad77e66093919318 [file] [log] [blame]
//===- InferFunctionAttrs.cpp - Infer implicit function attributes --------===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include "llvm/Transforms/IPO/InferFunctionAttrs.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Module.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
#define DEBUG_TYPE "inferattrs"
static bool inferAllPrototypeAttributes(
Module &M, function_ref<TargetLibraryInfo &(Function &)> GetTLI) {
bool Changed = false;
for (Function &F : M.functions())
// We only infer things using the prototype and the name; we don't need
// definitions. This ensures libfuncs are annotated and also allows our
// CGSCC inference to avoid needing to duplicate the inference from other
// attribute logic on all calls to declarations (as declarations aren't
// explicitly visited by CGSCC passes in the new pass manager.)
if (F.isDeclaration() && !F.hasOptNone()) {
if (!F.hasFnAttribute(Attribute::NoBuiltin))
Changed |= inferNonMandatoryLibFuncAttrs(F, GetTLI(F));
Changed |= inferAttributesFromOthers(F);
return Changed;
PreservedAnalyses InferFunctionAttrsPass::run(Module &M,
ModuleAnalysisManager &AM) {
FunctionAnalysisManager &FAM =
auto GetTLI = [&FAM](Function &F) -> TargetLibraryInfo & {
return FAM.getResult<TargetLibraryAnalysis>(F);
if (!inferAllPrototypeAttributes(M, GetTLI))
// 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();