[llvm] r348922 - [AMDGPU] Set metadata access for explicit section

[Piotr Sobczak via llvm-commits]

Author: piotr
Date: Wed Dec 12 03:20:04 2018
New Revision: 348922

URL: http://llvm.org/viewvc/llvm-project?rev=348922&view=rev
Log:
[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.

Reviewers: dstuttard, tpr, kzhuravl, nhaehnle, t-tye

Reviewed By: dstuttard, kzhuravl

Subscribers: llvm-commits, arsenm, jvesely, wdng, yaxunl, t-tye

Differential Revision: https://reviews.llvm.org/D55267

Added:
    llvm/trunk/test/CodeGen/AMDGPU/elf.metadata.ll
Modified:
    llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.cpp
    llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.h

Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.cpp?rev=348922&r1=348921&r2=348922&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.cpp Wed Dec 12 03:20:04 2018
@@ -29,3 +29,13 @@ MCSection *AMDGPUTargetObjectFile::Selec
 
   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);
+}

Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.h?rev=348922&r1=348921&r2=348922&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.h (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetObjectFile.h Wed Dec 12 03:20:04 2018
@@ -26,6 +26,8 @@ class AMDGPUTargetObjectFile : public Ta
   public:
     MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
                                       const TargetMachine &TM) const override;
+    MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
+                                        const TargetMachine &TM) const override;
 };
 
 } // end namespace llvm

Added: llvm/trunk/test/CodeGen/AMDGPU/elf.metadata.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/elf.metadata.ll?rev=348922&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/elf.metadata.ll (added)
+++ llvm/trunk/test/CodeGen/AMDGPU/elf.metadata.ll Wed Dec 12 03:20:04 2018
@@ -0,0 +1,56 @@
+; 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: }
+
+ at metadata_info_var_1 = internal global [4 x i32][i32 826559809, i32 826559809, i32 826559809, i32 826559809], align 1, section ".AMDGPU.metadata.info_1"
+ at metadata_info_var_2 = constant [4 x i32][i32 843337025, i32 843337025, i32 843337025, i32 843337025], align 1, section ".AMDGPU.metadata.info_2"
+ at metadata_info_var_3 = global [4 x i32][i32 860114241, i32 860114241, i32 860114241, i32 860114241], align 1, section ".AMDGPU.metadata.info_3"