Commit 8b2730d1 authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r228565: 

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r228565 | majnemer | 2015-02-08 22:31:31 -0800 (Sun, 08 Feb 2015) | 3 lines

MC: Calculate intra-section symbol differences correctly for COFF

This fixes PR22060.
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llvm-svn: 228667
parent 5e87af44

llvm/lib/MC/WinCOFFObjectWriter.cpp

+11 −6
Original line number Diff line number Diff line
@@ -710,17 +710,22 @@ void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm, 
    CrossSection = &Symbol.getSection() != &B->getSection();



    // Offset of the symbol in the section

    int64_t a = Layout.getSymbolOffset(&B_SD);

    int64_t OffsetOfB = Layout.getSymbolOffset(&B_SD);



    // Offset of the relocation in the section

    int64_t b = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();



    FixedValue = b - a;

    // In the case where we have SymbA and SymB, we just need to store the delta

    // between the two symbols.  Update FixedValue to account for the delta, and

    // skip recording the relocation.

    if (!CrossSection)

    if (!CrossSection) {

      int64_t OffsetOfA = Layout.getSymbolOffset(&A_SD);

      FixedValue = (OffsetOfA - OffsetOfB) + Target.getConstant();

      return;

    }



    // Offset of the relocation in the section

    int64_t OffsetOfRelocation =

        Layout.getFragmentOffset(Fragment) + Fixup.getOffset();



    FixedValue = OffsetOfRelocation - OffsetOfB;

  } else {

    FixedValue = Target.getConstant();

  }

llvm/test/MC/COFF/diff.s

+25 −0
Original line number Diff line number Diff line 
// RUN: llvm-mc -filetype=obj -triple i686-pc-mingw32 %s | llvm-readobj -s -sr -sd | FileCheck %s



.section baz, "xr"

	.def	X

	.scl	2;

	.type	32;

	.endef

	.globl	X

X:

	mov	Y-X+42,	%eax

	retl



	.def	Y

	.scl	2;

	.type	32;

	.endef

	.globl	Y

Y:

	retl



	.def	 _foobar;

	.scl	2;

	.type	32;
@@ -30,3 +48,10 @@ _rust_crate: 
// CHECK:        SectionData (

// CHECK-NEXT:     0000: 00000000 00000000 1C000000 20000000

// CHECK-NEXT:   )



// CHECK:        Name: baz

// CHECK:        Relocations [

// CHECK-NEXT:   ]

// CHECK:        SectionData (

// CHECK-NEXT:     0000: A1300000 00C3C3

// CHECK-NEXT:   )