On Darwin, ams printer should output a second label before a jump table so the linker knows it's a new atom. But this is only needed if the jump table is put in a separate section from the function body.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73720 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2009-06-18 20:37:15 +00:00
parent bcf9737f1e
commit b13bafe5c1
5 changed files with 20 additions and 15 deletions

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@ -347,8 +347,9 @@ void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
const char* JumpTableDataSection = TAI->getJumpTableDataSection();
const Function *F = MF.getFunction();
unsigned SectionFlags = TAI->SectionFlagsForGlobal(F);
bool JTInDiffSection = false;
if ((IsPic && !(LoweringInfo && LoweringInfo->usesGlobalOffsetTable())) ||
!JumpTableDataSection ||
!JumpTableDataSection ||
SectionFlags & SectionFlags::Linkonce) {
// In PIC mode, we need to emit the jump table to the same section as the
// function body itself, otherwise the label differences won't make sense.
@ -357,6 +358,7 @@ void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
SwitchToSection(TAI->SectionForGlobal(F));
} else {
SwitchToDataSection(JumpTableDataSection);
JTInDiffSection = true;
}
EmitAlignment(Log2_32(MJTI->getAlignment()));
@ -380,8 +382,10 @@ void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
// before each jump table. The first label is never referenced, but tells
// the assembler and linker the extents of the jump table object. The
// second label is actually referenced by the code.
if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
if (JTInDiffSection) {
if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
}
O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
<< '_' << i << ":\n";

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@ -74,10 +74,10 @@ ARMDarwinTargetAsmInfo::ARMDarwinTargetAsmInfo(const ARMTargetMachine &TM):
// In non-PIC modes, emit a special label before jump tables so that the
// linker can perform more accurate dead code stripping.
if (TM.getRelocationModel() != Reloc::PIC_) {
// Emit a local label that is preserved until the linker runs.
JumpTableSpecialLabelPrefix = "l";
}
// Emit a local label that is preserved until the linker runs.
// We do not check the relocation model here since it can be overridden
// later.
JumpTableSpecialLabelPrefix = "l";
NeedsSet = true;
DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";

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@ -68,10 +68,9 @@ PPCDarwinTargetAsmInfo::PPCDarwinTargetAsmInfo(const PPCTargetMachine &TM):
// In non-PIC modes, emit a special label before jump tables so that the
// linker can perform more accurate dead code stripping.
if (TM.getRelocationModel() != Reloc::PIC_) {
// Emit a local label that is preserved until the linker runs.
JumpTableSpecialLabelPrefix = "l";
}
// We do not check the relocation model here since it can be overridden
// later.
JumpTableSpecialLabelPrefix = "l";
}
/// PreferredEHDataFormat - This hook allows the target to select data

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@ -99,10 +99,10 @@ X86DarwinTargetAsmInfo::X86DarwinTargetAsmInfo(const X86TargetMachine &TM):
// In non-PIC modes, emit a special label before jump tables so that the
// linker can perform more accurate dead code stripping.
if (TM.getRelocationModel() != Reloc::PIC_) {
// Emit a local label that is preserved until the linker runs.
JumpTableSpecialLabelPrefix = "l";
}
// Emit a local label that is preserved until the linker runs.
// We do not check the relocation model here since it can be overridden
// later.
JumpTableSpecialLabelPrefix = "l";
SupportsDebugInformation = true;
NeedsSet = true;

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@ -1,6 +1,8 @@
; RUN: llvm-as < %s | llc -relocation-model=pic -mtriple=i386-linux-gnu -asm-verbose=false | not grep -F .text
; RUN: llvm-as < %s | llc -relocation-model=pic -mtriple=i686-apple-darwin -asm-verbose=false | not grep lea
; RUN: llvm-as < %s | llc -relocation-model=pic -mtriple=i686-apple-darwin -asm-verbose=false | grep add | count 2
; RUN: llvm-as < %s | llc -mtriple=x86_64-apple-darwin | not grep 'lJTI'
; rdar://6971437
declare void @_Z3bari(i32)