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Differential D55267

[AMDGPU] Set metadata access for explicit section
ClosedPublic

Authored by piotr on Dec 4 2018, 7:11 AM.

Details

Reviewers
dstuttard
tpr
kzhuravl
nhaehnle
t-tye
Commits
rG3732b4ce2590: [AMDGPU] Set metadata access for explicit section
rL348922: [AMDGPU] Set metadata access for explicit section
Summary

This patch provides a means to set Metadata section kind
for a global variable, if its explicit section name is
prefixed with ".AMDGPU.metadata."
This could be useful to make the global variable go to
an ELF section without any section flags set.

Diff Detail

Event Timeline

piotr created this revision.Dec 4 2018, 7:11 AM
Herald added subscribers: t-tye, yaxunl, wdng and 2 others. · View Herald TranscriptDec 4 2018, 7:11 AM
piotr added a subscriber: llvm-commits.Dec 10 2018, 1:09 AM
dstuttard accepted this revision.Dec 11 2018, 1:13 AM
dstuttard added a reviewer: t-tye.

LGTM - but probably need approval from one of the other reviewers as well

This revision is now accepted and ready to land.Dec 11 2018, 1:13 AM
kzhuravl accepted this revision.Dec 11 2018, 5:21 AM

LGTM

Closed by commit rL348922: [AMDGPU] Set metadata access for explicit section (authored by piotr). · Explain WhyDec 12 2018, 3:23 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
lib/
Target/
AMDGPU/
2 lines
10 lines
test/
CodeGen/
AMDGPU/
56 lines

Diff 176626

lib/Target/AMDGPU/AMDGPUTargetObjectFile.h

Show All 20 Lines
#include "llvm/Target/TargetMachine.h" #include "llvm/Target/TargetMachine.h"
namespace llvm { namespace llvm {
class AMDGPUTargetObjectFile : public TargetLoweringObjectFileELF { class AMDGPUTargetObjectFile : public TargetLoweringObjectFileELF {
public: public:
MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind, MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
const TargetMachine &TM) const override; const TargetMachine &TM) const override;
MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
const TargetMachine &TM) const override;
}; };
} // end namespace llvm } // end namespace llvm
#endif #endif

lib/Target/AMDGPU/AMDGPUTargetObjectFile.cpp

Show All 23 Lines
MCSection *AMDGPUTargetObjectFile::SelectSectionForGlobal( MCSection *AMDGPUTargetObjectFile::SelectSectionForGlobal(
const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const { const GlobalObject *GO, SectionKind Kind, const TargetMachine &TM) const {
if (Kind.isReadOnly() && AMDGPU::isReadOnlySegment(GO) && if (Kind.isReadOnly() && AMDGPU::isReadOnlySegment(GO) &&
AMDGPU::shouldEmitConstantsToTextSection(TM.getTargetTriple())) AMDGPU::shouldEmitConstantsToTextSection(TM.getTargetTriple()))
return TextSection; return TextSection;
return TargetLoweringObjectFileELF::SelectSectionForGlobal(GO, Kind, TM); return TargetLoweringObjectFileELF::SelectSectionForGlobal(GO, Kind, TM);
} }
MCSection *AMDGPUTargetObjectFile::getExplicitSectionGlobal(
const GlobalObject *GO, SectionKind SK, const TargetMachine &TM) const {
// Set metadata access for the explicit section
StringRef SectionName = GO->getSection();
if (SectionName.startswith(".AMDGPU.metadata."))
SK = SectionKind::getMetadata();
return TargetLoweringObjectFileELF::getExplicitSectionGlobal(GO, SK, TM);
}

test/CodeGen/AMDGPU/elf.metadata.ll

  • This file was added.
; RUN: llc < %s -march=amdgcn -mcpu=fiji -filetype=obj | llvm-readobj -symbols -s -sd - | FileCheck %s
; CHECK: Section {
; CHECK: Name: .AMDGPU.metadata.info_1
; CHECK: Type: SHT_PROGBITS (0x1)
; CHECK: Flags [ (0x0)
; CHECK: Size: 16
; CHECK: SectionData (
; CHECK: 0000: 414D4431 414D4431 414D4431 414D4431 |AMD1AMD1AMD1AMD1|
; CHECK: )
; CHECK: }
; CHECK: Section {
; CHECK: Name: .AMDGPU.metadata.info_2
; CHECK: Type: SHT_PROGBITS (0x1)
; CHECK: Flags [ (0x0)
; CHECK: Size: 16
; CHECK: SectionData (
; CHECK: 0000: 414D4432 414D4432 414D4432 414D4432 |AMD2AMD2AMD2AMD2|
; CHECK: )
; CHECK: }
; CHECK: Section {
; CHECK: Name: .AMDGPU.metadata.info_3
; CHECK: Type: SHT_PROGBITS (0x1)
; CHECK: Flags [ (0x0)
; CHECK: Size: 16
; CHECK: SectionData (
; CHECK: 0000: 414D4433 414D4433 414D4433 414D4433 |AMD3AMD3AMD3AMD3|
; CHECK: )
; CHECK: }
; CHECK: Symbol {
; CHECK: Name: metadata_info_var_1
; CHECK: Size: 16
; CHECK: Binding: Local
; CHECK: Section: .AMDGPU.metadata.info_1
; CHECK: }
; CHECK: Symbol {
; CHECK: Name: metadata_info_var_2
; CHECK: Size: 16
; CHECK: Binding: Global
; CHECK: Section: .AMDGPU.metadata.info_2
; CHECK: }
; CHECK: Symbol {
; CHECK: Name: metadata_info_var_3
; CHECK: Size: 16
; CHECK: Binding: Global
; CHECK: Section: .AMDGPU.metadata.info_3
; CHECK: }
@metadata_info_var_1 = internal global [4 x i32][i32 826559809, i32 826559809, i32 826559809, i32 826559809], align 1, section ".AMDGPU.metadata.info_1"
@metadata_info_var_2 = constant [4 x i32][i32 843337025, i32 843337025, i32 843337025, i32 843337025], align 1, section ".AMDGPU.metadata.info_2"
@metadata_info_var_3 = global [4 x i32][i32 860114241, i32 860114241, i32 860114241, i32 860114241], align 1, section ".AMDGPU.metadata.info_3"