From edd2bb863ec070f8cdef8ce110e5dfc97fe13745 Mon Sep 17 00:00:00 2001
From: Andy Ayers <andya@microsoft.com>
Date: Thu, 14 May 2015 01:10:41 +0000
Subject: [PATCH] Don't omit the constant when computing a cross-section
 relative relocation.

Differential Revision: http://reviews.llvm.org/D9692

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237327 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/MC/WinCOFFObjectWriter.cpp         |  2 +-
 test/MC/COFF/cross-section-relative.ll | 97 ++++++++++++++++++++++++++
 2 files changed, 98 insertions(+), 1 deletion(-)
 create mode 100644 test/MC/COFF/cross-section-relative.ll

diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp
index 58546307255..11a83791368 100644
--- a/lib/MC/WinCOFFObjectWriter.cpp
+++ b/lib/MC/WinCOFFObjectWriter.cpp
@@ -738,7 +738,7 @@ void WinCOFFObjectWriter::RecordRelocation(
     int64_t OffsetOfRelocation =
         Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
 
-    FixedValue = OffsetOfRelocation - OffsetOfB;
+    FixedValue = (OffsetOfRelocation - OffsetOfB) + Target.getConstant();
   } else {
     FixedValue = Target.getConstant();
   }
diff --git a/test/MC/COFF/cross-section-relative.ll b/test/MC/COFF/cross-section-relative.ll
new file mode 100644
index 00000000000..18823f8b29a
--- /dev/null
+++ b/test/MC/COFF/cross-section-relative.ll
@@ -0,0 +1,97 @@
+; Verify the assembler produces the expected expressions
+; RUN: llc -mtriple=x86_64-pc-win32 %s -o - | FileCheck %s
+; Verify the .fix data section conveys the right offsets and the right relocations
+; RUN: llc -mtriple=x86_64-pc-win32 -filetype=obj %s -o - | llvm-readobj -relocations -expand-relocs -sections -section-data | FileCheck %s --check-prefix=READOBJ
+
+;;;; some globals
+
+@g1 = constant i32 1;
+@g2 = constant i32 2;
+@g3 = constant i32 3;
+@g4 = constant i32 4;
+@__ImageBase = external global i64*;
+
+;;;; cross-section relative relocations
+
+; CHECK: .quad (g3-t1)+4
+@t1 = global i64 add(i64 sub(i64 ptrtoint(i32* @g3 to i64), i64 ptrtoint(i64* @t1 to i64)), i64 4), section ".fix"
+; CHECK: .quad g3-t2
+@t2 = global i64 sub(i64 ptrtoint(i32* @g3 to i64), i64 ptrtoint(i64* @t2 to i64)), section ".fix"
+; CHECK: .quad (g3-t3)-4
+@t3 = global i64 sub(i64 sub(i64 ptrtoint(i32* @g3 to i64), i64 ptrtoint(i64* @t3 to i64)), i64 4), section ".fix"
+; CHECK: .long g3-t4
+@t4 = global i32 trunc(i64 sub(i64 ptrtoint(i32* @g3 to i64), i64 ptrtoint(i32* @t4 to i64)) to i32), section ".fix"
+
+;;;; image base relocation
+
+; CHECK: .long g3@IMGREL
+@t5 = global i32 trunc(i64 sub(i64 ptrtoint(i32* @g3 to i64), i64 ptrtoint(i64** @__ImageBase to i64)) to i32), section ".fix"
+
+;;;; cross-section relative with source offset
+
+%struct.EEType = type { [2 x i8], i64, i32}
+
+; CHECK: .long g3-(t6+16)
+@t6 = global %struct.EEType { 
+        [2 x i8] c"\01\02", 
+        i64 256,
+        i32 trunc(i64 sub(i64 ptrtoint(i32* @g3 to i64), i64 ptrtoint(i32* getelementptr inbounds (%struct.EEType, %struct.EEType* @t6, i32 0, i32 2) to i64)) to i32 )
+}, section ".fix"
+
+; READOBJ:  Section {
+; READOBJ:    Number: 5
+; READOBJ:    Name: .fix (2E 66 69 78 00 00 00 00)
+; READOBJ:    VirtualSize: 0x0
+; READOBJ:    VirtualAddress: 0x0
+; READOBJ:    RawDataSize: 56
+; READOBJ:    PointerToRawData: 0xEC
+; READOBJ:    PointerToRelocations: 0x124
+; READOBJ:    PointerToLineNumbers: 0x0
+; READOBJ:    RelocationCount: 6
+; READOBJ:    LineNumberCount: 0
+; READOBJ:    Characteristics [ (0xC0500040)
+; READOBJ:      IMAGE_SCN_ALIGN_16BYTES (0x500000)
+; READOBJ:      IMAGE_SCN_CNT_INITIALIZED_DATA (0x40)
+; READOBJ:      IMAGE_SCN_MEM_READ (0x40000000)
+; READOBJ:      IMAGE_SCN_MEM_WRITE (0x80000000)
+; READOBJ:    ]
+; READOBJ:    SectionData (
+; READOBJ:      0000: 10000000 00000000 0C000000 00000000  |................|
+; READOBJ:      0010: 08000000 00000000 0C000000 00000000  |................|
+; READOBJ:      0020: 01020000 00000000 00010000 00000000  |................|
+; READOBJ:      0030: 0C000000 00000000                    |........|
+; READOBJ:    )
+; READOBJ:  }
+; READOBJ:  ]
+; READOBJ:  Relocations [
+; READOBJ:  Section (5) .fix {
+; READOBJ:    Relocation {
+; READOBJ:      Offset: 0x0
+; READOBJ:      Type: IMAGE_REL_AMD64_REL32 (4)
+; READOBJ:      Symbol: .rdata
+; READOBJ:    }
+; READOBJ:    Relocation {
+; READOBJ:      Offset: 0x8
+; READOBJ:      Type: IMAGE_REL_AMD64_REL32 (4)
+; READOBJ:      Symbol: .rdata
+; READOBJ:    }
+; READOBJ:    Relocation {
+; READOBJ:      Offset: 0x10
+; READOBJ:      Type: IMAGE_REL_AMD64_REL32 (4)
+; READOBJ:      Symbol: .rdata
+; READOBJ:    }
+; READOBJ:    Relocation {
+; READOBJ:      Offset: 0x18
+; READOBJ:      Type: IMAGE_REL_AMD64_REL32 (4)
+; READOBJ:      Symbol: .rdata
+; READOBJ:    }
+; READOBJ:    Relocation {
+; READOBJ:      Offset: 0x1C
+; READOBJ:      Type: IMAGE_REL_AMD64_ADDR32NB (3)
+; READOBJ:      Symbol: g3
+; READOBJ:    }
+; READOBJ:    Relocation {
+; READOBJ:      Offset: 0x30
+; READOBJ:      Type: IMAGE_REL_AMD64_REL32 (4)
+; READOBJ:      Symbol: .rdata
+; READOBJ:    }
-- 
2.34.1