Files
llvm-project/llvm/lib/Analysis/RuntimeLibcallInfo.cpp
Matt Arsenault 04c81a9973 CodeGen: Add LibcallLoweringInfo analysis pass (#168622)
The libcall lowering decisions should be program dependent,
depending on the current module's RuntimeLibcallInfo. We need
another related analysis derived from that plus the current
function's subtarget to provide concrete lowering decisions.

This takes on a somewhat unusual form. It's a Module analysis,
with a lookup keyed on the subtarget. This is a separate module
analysis from RuntimeLibraryAnalysis to avoid that depending on
codegen. It's not a function pass to avoid depending on any
particular function, to avoid repeated subtarget map lookups in
most of the use passes, and to avoid any recomputation in the
common case of one subtarget (and keeps it reusable across
repeated compilations).

This also switches ExpandFp and PreISelIntrinsicLowering as
a sample function and module pass. Note this is not yet wired
up to SelectionDAG, which is still using the LibcallLoweringInfo
constructed inside of TargetLowering.
2025-12-03 22:00:12 +01:00

62 lines
2.3 KiB
C++

//===- RuntimeLibcallInfo.cpp ---------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/RuntimeLibcallInfo.h"
#include "llvm/InitializePasses.h"
using namespace llvm;
AnalysisKey RuntimeLibraryAnalysis::Key;
RuntimeLibraryAnalysis::RuntimeLibraryAnalysis(const Triple &TT,
ExceptionHandling ExceptionModel,
FloatABI::ABIType FloatABI,
EABI EABIVersion,
StringRef ABIName,
VectorLibrary VecLib)
: LibcallsInfo(std::in_place, TT, ExceptionModel, FloatABI, EABIVersion,
ABIName, VecLib) {}
RTLIB::RuntimeLibcallsInfo
RuntimeLibraryAnalysis::run(const Module &M, ModuleAnalysisManager &) {
if (!LibcallsInfo)
LibcallsInfo = RTLIB::RuntimeLibcallsInfo(M);
return *LibcallsInfo;
}
INITIALIZE_PASS(RuntimeLibraryInfoWrapper, "runtime-library-info",
"Runtime Library Function Analysis", false, true)
RuntimeLibraryInfoWrapper::RuntimeLibraryInfoWrapper()
: ImmutablePass(ID), RTLA(RTLIB::RuntimeLibcallsInfo(Triple())) {}
RuntimeLibraryInfoWrapper::RuntimeLibraryInfoWrapper(
const Triple &TT, ExceptionHandling ExceptionModel,
FloatABI::ABIType FloatABI, EABI EABIVersion, StringRef ABIName,
VectorLibrary VecLib)
: ImmutablePass(ID), RTLCI(std::in_place, TT, ExceptionModel, FloatABI,
EABIVersion, ABIName, VecLib) {}
char RuntimeLibraryInfoWrapper::ID = 0;
ModulePass *llvm::createRuntimeLibraryInfoWrapperPass() {
return new RuntimeLibraryInfoWrapper();
}
void RuntimeLibraryInfoWrapper::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
// Assume this is stable unless explicitly invalidated.
bool RTLIB::RuntimeLibcallsInfo::invalidate(
Module &M, const PreservedAnalyses &PA,
ModuleAnalysisManager::Invalidator &) {
auto PAC = PA.getChecker<RuntimeLibraryAnalysis>();
return !PAC.preservedWhenStateless();
}