| 1 | //===----------------------------------------------------------------------===// |
|---|---|
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #include "llvm/Transforms/Instrumentation/PGOForceFunctionAttrs.h" |
| 10 | #include "llvm/Analysis/BlockFrequencyInfo.h" |
| 11 | #include "llvm/Analysis/ProfileSummaryInfo.h" |
| 12 | #include "llvm/IR/PassManager.h" |
| 13 | #include "llvm/Support/ErrorHandling.h" |
| 14 | |
| 15 | using namespace llvm; |
| 16 | |
| 17 | static bool shouldRunOnFunction(Function &F, ProfileSummaryInfo &PSI, |
| 18 | FunctionAnalysisManager &FAM) { |
| 19 | if (F.isDeclaration()) |
| 20 | return false; |
| 21 | // Respect existing attributes. |
| 22 | if (F.hasOptNone() || F.hasOptSize() || F.hasMinSize()) |
| 23 | return false; |
| 24 | if (F.hasFnAttribute(Attribute::Cold)) |
| 25 | return true; |
| 26 | if (!PSI.hasProfileSummary()) |
| 27 | return false; |
| 28 | BlockFrequencyInfo &BFI = FAM.getResult<BlockFrequencyAnalysis>(IR&: F); |
| 29 | return PSI.isFunctionColdInCallGraph(F: &F, BFI); |
| 30 | } |
| 31 | |
| 32 | PreservedAnalyses PGOForceFunctionAttrsPass::run(Module &M, |
| 33 | ModuleAnalysisManager &AM) { |
| 34 | if (ColdType == PGOOptions::ColdFuncOpt::Default) |
| 35 | return PreservedAnalyses::all(); |
| 36 | ProfileSummaryInfo &PSI = AM.getResult<ProfileSummaryAnalysis>(IR&: M); |
| 37 | FunctionAnalysisManager &FAM = |
| 38 | AM.getResult<FunctionAnalysisManagerModuleProxy>(IR&: M).getManager(); |
| 39 | bool MadeChange = false; |
| 40 | for (Function &F : M) { |
| 41 | if (!shouldRunOnFunction(F, PSI, FAM)) |
| 42 | continue; |
| 43 | switch (ColdType) { |
| 44 | case PGOOptions::ColdFuncOpt::Default: |
| 45 | llvm_unreachable("bailed out for default above"); |
| 46 | break; |
| 47 | case PGOOptions::ColdFuncOpt::OptSize: |
| 48 | F.addFnAttr(Attribute::OptimizeForSize); |
| 49 | break; |
| 50 | case PGOOptions::ColdFuncOpt::MinSize: |
| 51 | F.addFnAttr(Attribute::MinSize); |
| 52 | break; |
| 53 | case PGOOptions::ColdFuncOpt::OptNone: |
| 54 | // alwaysinline is incompatible with optnone. |
| 55 | if (F.hasFnAttribute(Attribute::AlwaysInline)) |
| 56 | continue; |
| 57 | F.addFnAttr(Attribute::OptimizeNone); |
| 58 | F.addFnAttr(Attribute::NoInline); |
| 59 | break; |
| 60 | } |
| 61 | MadeChange = true; |
| 62 | } |
| 63 | return MadeChange ? PreservedAnalyses::none() : PreservedAnalyses::all(); |
| 64 | } |
| 65 |