[llvm] Use TargetABI to assign default-target features in getDefaultSubtargetFeatures (PR #100833)
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llvm-commits at lists.llvm.org
Mon Sep 9 14:15:02 PDT 2024
https://github.com/hiraditya updated https://github.com/llvm/llvm-project/pull/100833
>From a65c4f556c1c417a16a1aacd0450afb07e3f90df Mon Sep 17 00:00:00 2001
From: AdityaK <hiraditya at msn.com>
Date: Fri, 26 Jul 2024 14:22:40 -0700
Subject: [PATCH] Use TargetABI to assign default-target features in
getDefaultSubtargetFeatures
It is currently not possible to provide any reasonable
target-features for compiler generated functions (See: #69780)
Having a target-abi will provide a way to add minimal
requirements for target-features like `+d` for RISC-V.
---
.../llvm/LTO/legacy/ThinLTOCodeGenerator.h | 2 +-
.../llvm/TargetParser/SubtargetFeature.h | 3 ++-
.../llvm/Transforms/Utils/ModuleUtils.h | 3 +++
llvm/lib/LTO/LTOBackend.cpp | 4 +++-
llvm/lib/LTO/LTOCodeGenerator.cpp | 3 ++-
llvm/lib/LTO/LTOModule.cpp | 3 ++-
llvm/lib/LTO/ThinLTOCodeGenerator.cpp | 21 ++++++++++++-------
llvm/lib/TargetParser/SubtargetFeature.cpp | 5 ++++-
llvm/lib/Transforms/Utils/ModuleUtils.cpp | 8 +++++++
9 files changed, 38 insertions(+), 14 deletions(-)
diff --git a/llvm/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h b/llvm/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h
index 7eb30d56e10c10..4ab1ca274dcd95 100644
--- a/llvm/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h
+++ b/llvm/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h
@@ -40,7 +40,7 @@ struct TargetMachineBuilder {
std::optional<Reloc::Model> RelocModel;
CodeGenOptLevel CGOptLevel = CodeGenOptLevel::Aggressive;
- std::unique_ptr<TargetMachine> create() const;
+ std::unique_ptr<TargetMachine> create(const StringRef TargetABI) const;
};
/// This class define an interface similar to the LTOCodeGenerator, but adapted
diff --git a/llvm/include/llvm/TargetParser/SubtargetFeature.h b/llvm/include/llvm/TargetParser/SubtargetFeature.h
index 2e1f00dad2df36..24d911a469627a 100644
--- a/llvm/include/llvm/TargetParser/SubtargetFeature.h
+++ b/llvm/include/llvm/TargetParser/SubtargetFeature.h
@@ -195,7 +195,8 @@ class SubtargetFeatures {
void dump() const;
/// Adds the default features for the specified target triple.
- void getDefaultSubtargetFeatures(const Triple& Triple);
+ void getDefaultSubtargetFeatures(const Triple &Triple,
+ const StringRef ABIInfo);
/// Determine if a feature has a flag; '+' or '-'
static bool hasFlag(StringRef Feature) {
diff --git a/llvm/include/llvm/Transforms/Utils/ModuleUtils.h b/llvm/include/llvm/Transforms/Utils/ModuleUtils.h
index 2a52d3ed1431e5..51fbb070751f90 100644
--- a/llvm/include/llvm/Transforms/Utils/ModuleUtils.h
+++ b/llvm/include/llvm/Transforms/Utils/ModuleUtils.h
@@ -97,6 +97,9 @@ void appendToUsed(Module &M, ArrayRef<GlobalValue *> Values);
/// Adds global values to the llvm.compiler.used list.
void appendToCompilerUsed(Module &M, ArrayRef<GlobalValue *> Values);
+/// Returns the TargetABI Metadata if present, empty StringRef otherwise.
+StringRef getTargetABIFromMD(Module &M);
+
/// Removes global values from the llvm.used and llvm.compiler.used arrays. \p
/// ShouldRemove should return true for any initializer field that should not be
/// included in the replacement global.
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index 4e58cd369c3ac9..d06b562655b93c 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -201,7 +201,9 @@ static std::unique_ptr<TargetMachine>
createTargetMachine(const Config &Conf, const Target *TheTarget, Module &M) {
StringRef TheTriple = M.getTargetTriple();
SubtargetFeatures Features;
- Features.getDefaultSubtargetFeatures(Triple(TheTriple));
+ StringRef TargetABI = llvm::getTargetABIFromMD(M);
+
+ Features.getDefaultSubtargetFeatures(Triple(TheTriple), TargetABI);
for (const std::string &A : Conf.MAttrs)
Features.AddFeature(A);
diff --git a/llvm/lib/LTO/LTOCodeGenerator.cpp b/llvm/lib/LTO/LTOCodeGenerator.cpp
index a192392e045851..f33e7f3c146d70 100644
--- a/llvm/lib/LTO/LTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/LTOCodeGenerator.cpp
@@ -402,7 +402,8 @@ bool LTOCodeGenerator::determineTarget() {
// Construct LTOModule, hand over ownership of module and target. Use MAttr as
// the default set of features.
SubtargetFeatures Features(join(Config.MAttrs, ""));
- Features.getDefaultSubtargetFeatures(Triple);
+ StringRef TargetABI = llvm::getTargetABIFromMD(*MergedModule);
+ Features.getDefaultSubtargetFeatures(Triple, TargetABI);
FeatureStr = Features.getString();
if (Config.CPU.empty())
Config.CPU = lto::getThinLTODefaultCPU(Triple);
diff --git a/llvm/lib/LTO/LTOModule.cpp b/llvm/lib/LTO/LTOModule.cpp
index eac78069f4d2bc..45152b60032c62 100644
--- a/llvm/lib/LTO/LTOModule.cpp
+++ b/llvm/lib/LTO/LTOModule.cpp
@@ -204,6 +204,7 @@ LTOModule::makeLTOModule(MemoryBufferRef Buffer, const TargetOptions &options,
if (TripleStr.empty())
TripleStr = sys::getDefaultTargetTriple();
llvm::Triple Triple(TripleStr);
+ StringRef TargetABI = llvm::getTargetABIFromMD(*M);
// find machine architecture for this module
std::string errMsg;
@@ -213,7 +214,7 @@ LTOModule::makeLTOModule(MemoryBufferRef Buffer, const TargetOptions &options,
// construct LTOModule, hand over ownership of module and target
SubtargetFeatures Features;
- Features.getDefaultSubtargetFeatures(Triple);
+ Features.getDefaultSubtargetFeatures(Triple, TargetABI);
std::string FeatureStr = Features.getString();
// Set a default CPU for Darwin triples.
std::string CPU;
diff --git a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
index 76268c950cf581..d6c5bbdcccf443 100644
--- a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -60,6 +60,7 @@
#include "llvm/Transforms/IPO/WholeProgramDevirt.h"
#include "llvm/Transforms/ObjCARC.h"
#include "llvm/Transforms/Utils/FunctionImportUtils.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
#include <numeric>
@@ -577,7 +578,8 @@ void ThinLTOCodeGenerator::crossReferenceSymbol(StringRef Name) {
}
// TargetMachine factory
-std::unique_ptr<TargetMachine> TargetMachineBuilder::create() const {
+std::unique_ptr<TargetMachine>
+TargetMachineBuilder::create(const StringRef TargetABI) const {
std::string ErrMsg;
const Target *TheTarget =
TargetRegistry::lookupTarget(TheTriple.str(), ErrMsg);
@@ -587,7 +589,7 @@ std::unique_ptr<TargetMachine> TargetMachineBuilder::create() const {
// Use MAttr as the default set of features.
SubtargetFeatures Features(MAttr);
- Features.getDefaultSubtargetFeatures(TheTriple);
+ Features.getDefaultSubtargetFeatures(TheTriple, TargetABI);
std::string FeatureStr = Features.getString();
std::unique_ptr<TargetMachine> TM(
@@ -913,10 +915,10 @@ void ThinLTOCodeGenerator::internalize(Module &TheModule,
*/
void ThinLTOCodeGenerator::optimize(Module &TheModule) {
initTMBuilder(TMBuilder, Triple(TheModule.getTargetTriple()));
-
+ StringRef TargetABI = llvm::getTargetABIFromMD(TheModule);
// Optimize now
- optimizeModule(TheModule, *TMBuilder.create(), OptLevel, Freestanding,
- DebugPassManager, nullptr);
+ optimizeModule(TheModule, *TMBuilder.create(TargetABI), OptLevel,
+ Freestanding, DebugPassManager, nullptr);
}
/// Write out the generated object file, either from CacheEntryPath or from
@@ -991,8 +993,10 @@ void ThinLTOCodeGenerator::run() {
auto TheModule = loadModuleFromInput(Mod.get(), Context, false,
/*IsImporting*/ false);
+ StringRef TargetABI = llvm::getTargetABIFromMD(*TheModule);
// CodeGen
- auto OutputBuffer = codegenModule(*TheModule, *TMBuilder.create());
+ auto OutputBuffer =
+ codegenModule(*TheModule, *TMBuilder.create(TargetABI));
if (SavedObjectsDirectoryPath.empty())
ProducedBinaries[count] = std::move(OutputBuffer);
else
@@ -1177,10 +1181,11 @@ void ThinLTOCodeGenerator::run() {
saveTempBitcode(*TheModule, SaveTempsDir, count, ".0.original.bc");
auto &ImportList = ImportLists[ModuleIdentifier];
+ StringRef TargetABI = llvm::getTargetABIFromMD(*TheModule);
// Run the main process now, and generates a binary
auto OutputBuffer = ProcessThinLTOModule(
- *TheModule, *Index, ModuleMap, *TMBuilder.create(), ImportList,
- ExportList, GUIDPreservedSymbols,
+ *TheModule, *Index, ModuleMap, *TMBuilder.create(TargetABI),
+ ImportList, ExportList, GUIDPreservedSymbols,
ModuleToDefinedGVSummaries[ModuleIdentifier], CacheOptions,
DisableCodeGen, SaveTempsDir, Freestanding, OptLevel, count,
DebugPassManager);
diff --git a/llvm/lib/TargetParser/SubtargetFeature.cpp b/llvm/lib/TargetParser/SubtargetFeature.cpp
index 2c51c403c19349..a1cdcc0acdf197 100644
--- a/llvm/lib/TargetParser/SubtargetFeature.cpp
+++ b/llvm/lib/TargetParser/SubtargetFeature.cpp
@@ -68,7 +68,8 @@ LLVM_DUMP_METHOD void SubtargetFeatures::dump() const {
}
#endif
-void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
+void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple &Triple,
+ const StringRef TargetABI) {
// FIXME: This is an inelegant way of specifying the features of a
// subtarget. It would be better if we could encode this information
// into the IR.
@@ -81,5 +82,7 @@ void SubtargetFeatures::getDefaultSubtargetFeatures(const Triple& Triple) {
AddFeature("64bit");
AddFeature("altivec");
}
+ } else if (Triple.isRISCV64() && TargetABI.contains("lp64d")) {
+ AddFeature("+d");
}
}
diff --git a/llvm/lib/Transforms/Utils/ModuleUtils.cpp b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
index 7249571f344938..52a59053cf6c0e 100644
--- a/llvm/lib/Transforms/Utils/ModuleUtils.cpp
+++ b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
@@ -163,6 +163,14 @@ void llvm::appendToCompilerUsed(Module &M, ArrayRef<GlobalValue *> Values) {
appendToUsedList(M, "llvm.compiler.used", Values);
}
+StringRef llvm::getTargetABIFromMD(Module &M) {
+ StringRef TargetABI = "";
+ if (auto *TargetABIMD =
+ dyn_cast_or_null<MDString>(M.getModuleFlag("target-abi")))
+ TargetABI = TargetABIMD->getString();
+ return TargetABI;
+}
+
static void removeFromUsedList(Module &M, StringRef Name,
function_ref<bool(Constant *)> ShouldRemove) {
GlobalVariable *GV = M.getNamedGlobal(Name);
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