Commit 47046f05 authored by Martin Storsjö's avatar Martin Storsjö
Browse files

[MC] Produce proper section relative relocations for COFF in .debug_frame 

The third parameter to Streamer.EmitSymbolValue() is "bool
IsSectionRelative = false".

For ELF, these debug sections are mapped to address zero, so a normal,
absolute address relocation works just fine, but COFF needs a section
relative relocation, and COFF is the only target where
needsDwarfSectionOffsetDirective() returns true. This matches how
EmitSymbolValue is called elsewhere in the same source file.

Differential Revision: https://reviews.llvm.org/D70661
parent 943513b7

llvm/lib/MC/MCDwarf.cpp

+2 −1
Original line number Diff line number Diff line
@@ -1701,7 +1701,8 @@ void FrameEmitterImpl::EmitFDE(const MCSymbol &cieStart, 
        MakeStartMinusEndExpr(Streamer, SectionStart, cieStart, 0);

    emitAbsValue(Streamer, offset, 4);

  } else {

    Streamer.EmitSymbolValue(&cieStart, 4);

    Streamer.EmitSymbolValue(&cieStart, 4,

                             asmInfo->needsDwarfSectionOffsetDirective());

  }



  // PC Begin

llvm/test/MC/COFF/cfi-sections.s

0 → 100644
+26 −0
Original line number Diff line number Diff line 
// RUN: llvm-mc -filetype=obj -triple x86_64-mingw32 %s -o - | llvm-objdump -r - | FileCheck --check-prefix=COFF_X86_64 %s

// RUN: llvm-mc -filetype=obj -triple i686-mingw32 %s -o - | llvm-objdump -r - | FileCheck --check-prefix=COFF_I686 %s



.cfi_sections .debug_frame



f1:

        .cfi_startproc

        nop

        .cfi_endproc



f2:

        .cfi_startproc

        nop

        .cfi_endproc



// COFF_X86_64: RELOCATION RECORDS FOR [.debug_frame]:

// COFF_X86_64-NEXT: {{.*}} IMAGE_REL_AMD64_SECREL .debug_frame

// COFF_X86_64-NEXT: {{.*}} IMAGE_REL_AMD64_ADDR64 .text

// COFF_X86_64-NEXT: {{.*}} IMAGE_REL_AMD64_SECREL .debug_frame

// COFF_X86_64-NEXT: {{.*}} IMAGE_REL_AMD64_ADDR64 .text



// COFF_I686: RELOCATION RECORDS FOR [.debug_frame]:

// COFF_I686-NEXT: {{.*}} IMAGE_REL_I386_SECREL .debug_frame

// COFF_I686-NEXT: {{.*}} IMAGE_REL_I386_DIR32 .text

// COFF_I686-NEXT: {{.*}} IMAGE_REL_I386_SECREL .debug_frame

// COFF_I686-NEXT: {{.*}} IMAGE_REL_I386_DIR32 .text