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Put jump tables in distinct sections if -ffunction-sections is used. 

A small regression in r230411 was that we were basing the decision on
-fdata-sections.

llvm-svn: 230707
This commit is contained in:
Rafael Espindola 2015-02-26 23:55:11 +00:00
parent 44949ff3e1
commit 4491d0d337
2 changed files with 34 additions and 20 deletions
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48
llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
View File

@ -244,22 +244,9 @@ static StringRef getSectionPrefixForGlobal(SectionKind Kind) {
return ".data.rel.ro";
}
const MCSection *TargetLoweringObjectFileELF::
SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler &Mang, const TargetMachine &TM) const {
unsigned Flags = getELFSectionFlags(Kind);
// If we have -ffunction-section or -fdata-section then we should emit the
// global value to a uniqued section specifically for it.
bool EmitUniqueSection = false;
if (!(Flags & ELF::SHF_MERGE) && !Kind.isCommon()) {
if (Kind.isText())
EmitUniqueSection = TM.getFunctionSections();
else
EmitUniqueSection = TM.getDataSections();
}
EmitUniqueSection |= GV->hasComdat();
static const MCSectionELF *selectELFSectionForGlobal(
MCContext &Ctx, const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
const TargetMachine &TM, bool EmitUniqueSection, unsigned Flags) {
unsigned EntrySize = 0;
if (Kind.isMergeableCString()) {
if (Kind.isMergeable2ByteCString()) {
@ -309,9 +296,29 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
Name.push_back('.');
TM.getNameWithPrefix(Name, GV, Mang, true);
}
return getContext().getELFSection(Name, getELFSectionType(Name, Kind), Flags,
EntrySize, Group,
EmitUniqueSection && !UniqueSectionNames);
return Ctx.getELFSection(Name, getELFSectionType(Name, Kind), Flags,
EntrySize, Group,
EmitUniqueSection && !UniqueSectionNames);
}
const MCSection *TargetLoweringObjectFileELF::SelectSectionForGlobal(
const GlobalValue *GV, SectionKind Kind, Mangler &Mang,
const TargetMachine &TM) const {
unsigned Flags = getELFSectionFlags(Kind);
// If we have -ffunction-section or -fdata-section then we should emit the
// global value to a uniqued section specifically for it.
bool EmitUniqueSection = false;
if (!(Flags & ELF::SHF_MERGE) && !Kind.isCommon()) {
if (Kind.isText())
EmitUniqueSection = TM.getFunctionSections();
else
EmitUniqueSection = TM.getDataSections();
}
EmitUniqueSection |= GV->hasComdat();
return selectELFSectionForGlobal(getContext(), GV, Kind, Mang, TM,
EmitUniqueSection, Flags);
}
const MCSection *TargetLoweringObjectFileELF::getSectionForJumpTable(
@ -323,7 +330,8 @@ const MCSection *TargetLoweringObjectFileELF::getSectionForJumpTable(
if (!EmitUniqueSection)
return ReadOnlySection;
return SelectSectionForGlobal(&F, SectionKind::getReadOnly(), Mang, TM);
return selectELFSectionForGlobal(getContext(), &F, SectionKind::getReadOnly(),
Mang, TM, EmitUniqueSection, ELF::SHF_ALLOC);
}
bool TargetLoweringObjectFileELF::shouldPutJumpTableInFunctionSection(

6
llvm/test/CodeGen/X86/global-sections.ll
View File

@ -3,6 +3,7 @@
; RUN: llc < %s -mtriple=i386-apple-darwin10 -relocation-model=static | FileCheck %s -check-prefix=DARWIN-STATIC
; RUN: llc < %s -mtriple=x86_64-apple-darwin10 | FileCheck %s -check-prefix=DARWIN64
; RUN: llc < %s -mtriple=i386-unknown-linux-gnu -data-sections -function-sections | FileCheck %s -check-prefix=LINUX-SECTIONS
; RUN: llc < %s -mtriple=i386-unknown-linux-gnu -function-sections | FileCheck %s -check-prefix=LINUX-FUNC-SECTIONS
; RUN: llc < %s -mtriple=x86_64-pc-linux -data-sections -function-sections -relocation-model=pic | FileCheck %s -check-prefix=LINUX-SECTIONS-PIC
; RUN: llc < %s -mtriple=i686-pc-win32 -data-sections -function-sections | FileCheck %s -check-prefix=WIN32-SECTIONS
@ -42,6 +43,11 @@ bb5:
; LINUX-SECTIONS-NEXT: .cfi_endproc
; LINUX-SECTIONS-NEXT: .section .rodata.F2,"a",@progbits
; LINUX-FUNC-SECTIONS: .section .text.F2,"ax",@progbits
; LINUX-FUNC-SECTIONS: .size F2,
; LINUX-FUNC-SECTIONS-NEXT: .cfi_endproc
; LINUX-FUNC-SECTIONS-NEXT: .section .rodata.F2,"a",@progbits
; LINUX-SECTIONS-PIC: .section .text.F2,"ax",@progbits
; LINUX-SECTIONS-PIC: .size F2,
; LINUX-SECTIONS-PIC-NEXT: .cfi_endproc