| //===--- MisExpect.h - Check the use of llvm.expect with PGO data ---------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This contains code to emit diagnostic messages for potentially incorrect |
| // usage of the llvm.expect intrinsic. This utility extracts the threshold |
| // values from metadata associated with the instrumented Branch or Switch |
| // instruction. The threshold values are then used to determine if a diagnostic |
| // should be emitted. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_TRANSFORMS_UTILS_MISEXPECT_H |
| #define LLVM_TRANSFORMS_UTILS_MISEXPECT_H |
| |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/Instructions.h" |
| #include "llvm/IR/LLVMContext.h" |
| |
| namespace llvm { |
| namespace misexpect { |
| |
| /// checkBackendInstrumentation - compares PGO counters to the thresholds used |
| /// for llvm.expect and warns if the PGO counters are outside of the expected |
| /// range. It extracts the expected weights from the MD_prof weights attatched |
| /// to the instruction, which are are assumed to come from lowered llvm.expect |
| /// intrinsics. The RealWeights parameter and the extracted expected weights are |
| /// then passed to verifyMisexpect() for verification |
| /// |
| /// \param I The Instruction being checked |
| /// \param RealWeights A vector of profile weights for each target block |
| void checkBackendInstrumentation(Instruction &I, |
| const llvm::ArrayRef<uint32_t> RealWeights); |
| |
| /// checkFrontendInstrumentation - compares PGO counters to the thresholds used |
| /// for llvm.expect and warns if the PGO counters are outside of the expected |
| /// range. It extracts the expected weights from the MD_prof weights attatched |
| /// to the instruction, which are are assumed to come from profiling data |
| /// attached by the frontend prior to llvm.expect intrinsic lowering. The |
| /// ExpectedWeights parameter and the extracted real weights are then passed to |
| /// verifyMisexpect() for verification |
| /// |
| /// \param I The Instruction being checked |
| /// \param ExpectedWeights A vector of the expected weights for each target |
| /// block, this determines the threshold values used when emiting diagnostics |
| void checkFrontendInstrumentation(Instruction &I, |
| const ArrayRef<uint32_t> ExpectedWeights); |
| |
| /// veryifyMisExpect - compares RealWeights to the thresholds used |
| /// for llvm.expect and warns if the PGO counters are outside of the expected |
| /// range. |
| /// |
| /// \param I The Instruction being checked |
| /// \param RealWeights A vector of profile weights from the profile data |
| /// \param ExpectedWeights A vector of the weights attatch by llvm.expect |
| void verifyMisExpect(Instruction &I, ArrayRef<uint32_t> RealWeights, |
| const ArrayRef<uint32_t> ExpectedWeights); |
| |
| /// checkExpectAnnotations - compares PGO counters to the thresholds used |
| /// for llvm.expect and warns if the PGO counters are outside of the expected |
| /// range. It extracts the expected weights from the MD_prof weights attatched |
| /// to the instruction, which are are assumed to come from lowered llvm.expect |
| /// intrinsics. The RealWeights parameter and the extracted expected weights are |
| /// then passed to verifyMisexpect() for verification. It is a thin wrapper |
| /// around the checkFrontendInstrumentation and checkBackendInstrumentation APIs |
| /// |
| /// \param I The Instruction being checked |
| /// \param ExistingWeights A vector of profile weights for each target block |
| /// \param IsFrontend A boolean describing if this is Frontend instrumentation |
| void checkExpectAnnotations(Instruction &I, |
| const ArrayRef<uint32_t> ExistingWeights, |
| bool IsFrontend); |
| |
| } // namespace misexpect |
| } // namespace llvm |
| |
| #endif |