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Revert "IRGen: Always eliminate frame pointers of leaf functions" #31993

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Revert "IRGen: Always eliminate frame pointers of leaf functions" #31993

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2 changes: 0 additions & 2 deletions include/swift/AST/IRGenOptions.h
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Original file line number Diff line number Diff line change
Expand Up @@ -191,7 +191,6 @@ class IRGenOptions {
unsigned DisableLLVMSLPVectorizer : 1;

/// Disable frame pointer elimination?
unsigned DisableFPElimLeaf : 1;
unsigned DisableFPElim : 1;

/// Special codegen for playgrounds.
Expand Down Expand Up @@ -320,7 +319,6 @@ class IRGenOptions {
DisableClangModuleSkeletonCUs(false), UseJIT(false),
DisableLLVMOptzns(false),
DisableSwiftSpecificLLVMOptzns(false), DisableLLVMSLPVectorizer(false),
DisableFPElimLeaf(false),
DisableFPElim(true), Playground(false), EmitStackPromotionChecks(false),
FunctionSections(false), PrintInlineTree(false), EmbedMode(IRGenEmbedMode::None),
HasValueNamesSetting(false), ValueNames(false),
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4 changes: 0 additions & 4 deletions include/swift/Option/Options.td
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Expand Up @@ -1010,10 +1010,6 @@ def enable_private_imports : Flag<["-"], "enable-private-imports">,
Flags<[FrontendOption, NoInteractiveOption, HelpHidden]>,
HelpText<"Allows this module's internal and private API to be accessed">;

def disable_leaf_frame_pointer_elim : Flag<["-"], "no-omit-leaf-frame-pointer">,
Flags<[FrontendOption, NoInteractiveOption, HelpHidden]>,
HelpText<"Don't omit the frame pointer for leaf functions">;

def sanitize_EQ : CommaJoined<["-"], "sanitize=">,
Flags<[FrontendOption, NoInteractiveOption]>, MetaVarName<"<check>">,
HelpText<"Turn on runtime checks for erroneous behavior.">;
Expand Down
2 changes: 0 additions & 2 deletions lib/Driver/ToolChains.cpp
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Expand Up @@ -288,8 +288,6 @@ void ToolChain::addCommonFrontendArgs(const OutputInfo &OI,
arguments.push_back("-enable-anonymous-context-mangled-names");
}

inputArgs.AddLastArg(arguments, options::OPT_disable_leaf_frame_pointer_elim);

// Pass through any subsystem flags.
inputArgs.AddAllArgs(arguments, options::OPT_Xllvm);
inputArgs.AddAllArgs(arguments, options::OPT_Xcc);
Expand Down
3 changes: 0 additions & 3 deletions lib/Frontend/CompilerInvocation.cpp
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Expand Up @@ -1514,9 +1514,6 @@ static bool ParseIRGenArgs(IRGenOptions &Opts, ArgList &Args,
getRuntimeCompatVersion();
}

if (Args.hasArg(OPT_disable_leaf_frame_pointer_elim))
Opts.DisableFPElimLeaf = true;

return false;
}

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58 changes: 16 additions & 42 deletions lib/IRGen/IRGenModule.cpp
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Expand Up @@ -90,34 +90,21 @@ static llvm::PointerType *createStructPointerType(IRGenModule &IGM,
return createStructType(IGM, name, types)->getPointerTo(DefaultAS);
};

static clang::CodeGenOptions::FramePointerKind
shouldUseFramePointer(const IRGenOptions &Opts, const llvm::Triple &triple) {
if (Opts.DisableFPElim) {
// General frame pointer elimination is disabled.
// Should we at least eliminate in leaf functions?
// Currently we only do that on arm64 (this matches the behavior of clang).
return Opts.DisableFPElimLeaf
? clang::CodeGenOptions::FramePointerKind::All
: triple.isAArch64()
? clang::CodeGenOptions::FramePointerKind::NonLeaf
: clang::CodeGenOptions::FramePointerKind::All;
}

return clang::CodeGenOptions::FramePointerKind::None;
}

static clang::CodeGenerator *
createClangCodeGenerator(ASTContext &Context, llvm::LLVMContext &LLVMContext,
const IRGenOptions &Opts, StringRef ModuleName,
StringRef PD, const llvm::Triple &triple) {
static clang::CodeGenerator *createClangCodeGenerator(ASTContext &Context,
llvm::LLVMContext &LLVMContext,
const IRGenOptions &Opts,
StringRef ModuleName,
StringRef PD) {
auto Loader = Context.getClangModuleLoader();
auto *Importer = static_cast<ClangImporter*>(&*Loader);
assert(Importer && "No clang module loader!");
auto &ClangContext = Importer->getClangASTContext();

auto &CGO = Importer->getClangCodeGenOpts();
CGO.OptimizationLevel = Opts.shouldOptimize() ? 3 : 0;
CGO.setFramePointer(shouldUseFramePointer(Opts, triple));
CGO.setFramePointer(Opts.DisableFPElim
? clang::CodeGenOptions::FramePointerKind::All
: clang::CodeGenOptions::FramePointerKind::None);
CGO.DiscardValueNames = !Opts.shouldProvideValueNames();
switch (Opts.DebugInfoLevel) {
case IRGenDebugInfoLevel::None:
Expand Down Expand Up @@ -207,17 +194,17 @@ static void sanityCheckStdlib(IRGenModule &IGM) {

IRGenModule::IRGenModule(IRGenerator &irgen,
std::unique_ptr<llvm::TargetMachine> &&target,
SourceFile *SF, StringRef ModuleName,
StringRef OutputFilename,
SourceFile *SF,
StringRef ModuleName, StringRef OutputFilename,
StringRef MainInputFilenameForDebugInfo,
StringRef PrivateDiscriminator)
: LLVMContext(new llvm::LLVMContext()), IRGen(irgen),
Context(irgen.SIL.getASTContext()),
: LLVMContext(new llvm::LLVMContext()),
IRGen(irgen), Context(irgen.SIL.getASTContext()),
// The LLVMContext (and the IGM itself) will get deleted by the IGMDeleter
// as long as the IGM is registered with the IRGenerator.
ClangCodeGen(createClangCodeGenerator(Context, *LLVMContext, irgen.Opts,
ModuleName, PrivateDiscriminator,
irgen.getEffectiveClangTriple())),
ClangCodeGen(createClangCodeGenerator(Context, *LLVMContext,
irgen.Opts,
ModuleName, PrivateDiscriminator)),
Module(*ClangCodeGen->GetModule()),
DataLayout(irgen.getClangDataLayout()),
Triple(irgen.getEffectiveClangTriple()), TargetMachine(std::move(target)),
Expand Down Expand Up @@ -1001,20 +988,7 @@ bool swift::irgen::shouldRemoveTargetFeature(StringRef feature) {

void IRGenModule::setHasFramePointer(llvm::AttrBuilder &Attrs,
bool HasFramePointer) {
if (!HasFramePointer) {
Attrs.addAttribute("frame-pointer", "none");
return;
}
if (IRGen.Opts.DisableFPElimLeaf) {
Attrs.addAttribute("frame-pointer", "all");
return;
}

// We omit frame pointers for leaf functions only for arm64 for now (matching
// clang's behavior).
auto framePointer =
IRGen.getEffectiveClangTriple().isAArch64() ? "non-leaf" : "all";
Attrs.addAttribute("frame-pointer", framePointer);
Attrs.addAttribute("frame-pointer", HasFramePointer ? "all" : "none");
}

void IRGenModule::setHasFramePointer(llvm::Function *F,
Expand Down
64 changes: 0 additions & 64 deletions test/IRGen/framepointer.sil
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This file was deleted.

73 changes: 0 additions & 73 deletions test/IRGen/framepointer_arm64.sil
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6 changes: 6 additions & 0 deletions test/Misc/tbi.sil
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Original file line number Diff line number Diff line change
Expand Up @@ -19,13 +19,19 @@

// NO_TBI-LABEL: .globl _testTBI
// NO_TBI: _testTBI
// NO_TBI-NEXT: stp
// NO_TBI-NEXT: mov
// NO_TBI-NEXT: and
// NO_TBI-NEXT: ldr
// NO_TBI-NEXT: ldp
// NO_TBI-NEXT: ret

// TBI-LABEL: .globl _testTBI
// TBI: _testTBI:
// TBI-NEXT: stp
// TBI-NEXT: mov
// TBI-NEXT: ldr
// TBI-NEXT: ldp
// TBI-NEXT: ret

sil_stage canonical
Expand Down