Skip to content

[clang][ARM] disable frame pointers by default for bare metal ARM targets #117140

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
stuij merged 7 commits into from
Dec 6, 2024
Merged

[clang][ARM] disable frame pointers by default for bare metal ARM targets #117140

Show file tree
Hide file tree
Changes from 6 commits
Commits
Show all changes
7 commits
Select commit Hold shift + click to select a range
4a85a0c
[clang][ARM] disable frame pointers by default for bare metal ARM tar…
stuij Nov 15, 2024
51a5d72
fix clang -> toolchains closing brace comment mislabel
stuij Nov 21, 2024
9aeb61f
Remove braces around single statement `if` body
stuij Nov 21, 2024
d953a8d
Add Apple embedded tests
stuij Nov 26, 2024
b972b8b
satisfy clang-format
stuij Nov 26, 2024
26c854f
Rename isARMBareMetal -> isArmEABIBareMetal
stuij Nov 29, 2024
cc3b138
Move isARMEABIBareMetal to clang/lib/Driver/ToolChains/Arch/ARM.cpp
stuij Dec 3, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
19 changes: 12 additions & 7 deletions clang/lib/Driver/ToolChains/BareMetal.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -128,12 +128,14 @@ BareMetal::BareMetal(const Driver &D, const llvm::Triple &Triple,
}
}

namespace clang {
namespace driver {
namespace toolchains {
/// Is the triple {arm,armeb,thumb,thumbeb}-none-none-{eabi,eabihf} ?
static bool isARMBareMetal(const llvm::Triple &Triple) {
if (Triple.getArch() != llvm::Triple::arm &&
Triple.getArch() != llvm::Triple::thumb &&
Triple.getArch() != llvm::Triple::armeb &&
Triple.getArch() != llvm::Triple::thumbeb)
bool isARMEABIBareMetal(const llvm::Triple &Triple) {
auto arch = Triple.getArch();
if (arch != llvm::Triple::arm && arch != llvm::Triple::thumb &&
arch != llvm::Triple::armeb && arch != llvm::Triple::thumbeb)
return false;

if (Triple.getVendor() != llvm::Triple::UnknownVendor)
Expand All @@ -148,6 +150,9 @@ static bool isARMBareMetal(const llvm::Triple &Triple) {

return true;
}
} // namespace toolchains
} // namespace driver
} // namespace clang

/// Is the triple {aarch64.aarch64_be}-none-elf?
static bool isAArch64BareMetal(const llvm::Triple &Triple) {
Expand Down Expand Up @@ -267,7 +272,7 @@ void BareMetal::findMultilibs(const Driver &D, const llvm::Triple &Triple,
}

bool BareMetal::handlesTarget(const llvm::Triple &Triple) {
return isARMBareMetal(Triple) || isAArch64BareMetal(Triple) ||
return isARMEABIBareMetal(Triple) || isAArch64BareMetal(Triple) ||
isRISCVBareMetal(Triple) || isPPCBareMetal(Triple);
}

Expand Down Expand Up @@ -561,7 +566,7 @@ void baremetal::Linker::ConstructJob(Compilation &C, const JobAction &JA,
// The R_ARM_TARGET2 relocation must be treated as R_ARM_REL32 on arm*-*-elf
// and arm*-*-eabi (the default is R_ARM_GOT_PREL, used on arm*-*-linux and
// arm*-*-*bsd).
if (isARMBareMetal(TC.getTriple()))
if (isARMEABIBareMetal(TC.getTriple()))
CmdArgs.push_back("--target2=rel");

CmdArgs.push_back("-o");
Expand Down
2 changes: 2 additions & 0 deletions clang/lib/Driver/ToolChains/BareMetal.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -19,6 +19,8 @@ namespace driver {

namespace toolchains {

bool isARMEABIBareMetal(const llvm::Triple &Triple);

class LLVM_LIBRARY_VISIBILITY BareMetal : public ToolChain {
public:
BareMetal(const Driver &D, const llvm::Triple &Triple,
Expand Down
4 changes: 4 additions & 0 deletions clang/lib/Driver/ToolChains/CommonArgs.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -19,6 +19,7 @@
#include "Arch/SystemZ.h"
#include "Arch/VE.h"
#include "Arch/X86.h"
#include "BareMetal.h"
#include "HIPAMD.h"
#include "Hexagon.h"
#include "MSP430.h"
Expand Down Expand Up @@ -151,6 +152,9 @@ static bool useFramePointerForTargetByDefault(const llvm::opt::ArgList &Args,
}
}

if (toolchains::isARMEABIBareMetal(Triple))
return false;

return true;
}

Expand Down
53 changes: 53 additions & 0 deletions clang/test/Driver/frame-pointer-elim.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -162,5 +162,58 @@
// RUN: FileCheck --check-prefix=KEEP-NON-LEAF %s
// RUN: not %clang -### --target=riscv64-linux-android -mbig-endian -O1 -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NON-LEAF %s

// On ARM backend bare metal targets, frame pointer is omitted
// RUN: %clang -### --target=arm-arm-none-eabi -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s
// RUN: %clang -### --target=arm-arm-none-eabihf -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s
// RUN: %clang -### --target=arm-arm-none-eabi -S -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-arm-none-eabihf -S -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-arm-none-eabi -S -O1 %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s
// RUN: %clang -### --target=arm-arm-none-eabihf -S -O1 %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s
// RUN: %clang -### --target=arm-arm-none-eabi -S -O1 -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-arm-none-eabihf -S -O1 -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=armeb-arm-none-eabi -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s
// RUN: %clang -### --target=thumb-arm-none-eabi -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s
// RUN: %clang -### --target=thumbeb-arm-none-eabi -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NONE %s

// Check that for Apple bare metal targets, we're keeping frame pointers by default
// RUN: %clang -### --target=thumbv6m-apple-none-macho -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=thumbv6m-apple-none-macho -S -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-apple-none-macho -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-apple-none-macho -S -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=thumbv6m-apple-none-macho -S -O1 %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=thumbv6m-apple-none-macho -S -O1 -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-apple-none-macho -S -O1 %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s
// RUN: %clang -### --target=arm-apple-none-macho -S -O1 -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-ALL %s

// AArch64 bare metal targets behave like hosted targets
// RUN: %clang -### --target=aarch64-none-elf -S %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NON-LEAF %s
// RUN: %clang -### --target=aarch64-none-elf -S -O1 %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NON-LEAF %s
// RUN: %clang -### --target=aarch64-none-elf -S -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NON-LEAF %s
// RUN: %clang -### --target=aarch64-none-elf -S -O1 -fno-omit-frame-pointer %s 2>&1 | \
// RUN: FileCheck --check-prefix=KEEP-NON-LEAF %s

void f0() {}
void f1() { f0(); }