From 8a14aa1bd96a59b2997c4a88907bd895e3ef3efb Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@google.com>
Date: Fri, 2 Aug 2013 18:40:50 +0000
Subject: [PATCH] [PECOFF] Relocations now take into account the address which
 is stored at the relocation site

Patch by Ron Ofir.

llvm-svn: 187664
---
 lld/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp |  2 ++
 lld/test/pecoff/Inputs/reloc.obj.yaml        | 53 ++++++++++++++++++++++++++++
 lld/test/pecoff/reloc.test                   | 46 +++++++++++++++---------
 3 files changed, 84 insertions(+), 17 deletions(-)
 create mode 100644 lld/test/pecoff/Inputs/reloc.obj.yaml

diff --git a/lld/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp b/lld/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp
index d7d8176..f8ee81d 100644
--- a/lld/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp
+++ b/lld/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp
@@ -290,6 +290,8 @@ public:
         auto relocSite = reinterpret_cast<ulittle32_t *>(
             fileBuffer + layout->_fileOffset + ref->offsetInAtom());
         uint64_t targetAddr = atomRva[ref->target()];
+        // Also account for whatever offset is already stored at the relocation site.
+        targetAddr += *relocSite;
 
         // Skip if this reference is not for relocation.
         if (ref->kind() < lld::Reference::kindTargetLow)
diff --git a/lld/test/pecoff/Inputs/reloc.obj.yaml b/lld/test/pecoff/Inputs/reloc.obj.yaml
new file mode 100644
index 0000000..7143fd3
--- /dev/null
+++ b/lld/test/pecoff/Inputs/reloc.obj.yaml
@@ -0,0 +1,53 @@
+---
+header:
+  Machine:         IMAGE_FILE_MACHINE_I386
+  Characteristics: [  ]
+sections:
+  - Name:            .text
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     5589E583EC14C745FC00000000C744240C00000000C744240807000000C744240400000000C7042400000000FF150000000083EC1031C083C4145DC3
+    Relocations:
+      - VirtualAddress:  25
+        SymbolName:      .data
+        Type:            IMAGE_REL_I386_DIR32
+      - VirtualAddress:  33
+        SymbolName:      .data
+        Type:            IMAGE_REL_I386_DIR32
+      - VirtualAddress:  46
+        SymbolName:      __imp__MessageBoxA@16
+        Type:            IMAGE_REL_I386_DIR32
+  - Name:            .data
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ, IMAGE_SCN_MEM_WRITE ]
+    Alignment:       4
+    SectionData:     576F726C64210048656C6C6F2C00
+symbols:
+  - Name:            .text
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    NumberOfAuxSymbols: 1
+    AuxiliaryData:   3C0000000300000000000000010000000000
+  - Name:            .data
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    NumberOfAuxSymbols: 1
+    AuxiliaryData:   0E0000000000000000000000020000000000
+  - Name:            _main
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            __imp__MessageBoxA@16
+    Value:           0
+    SectionNumber:   0
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...
diff --git a/lld/test/pecoff/reloc.test b/lld/test/pecoff/reloc.test
index 6aee896..8dd5c47 100644
--- a/lld/test/pecoff/reloc.test
+++ b/lld/test/pecoff/reloc.test
@@ -1,4 +1,4 @@
-# RUN: yaml2obj %p/Inputs/hello.obj.yaml > %t.obj
+# RUN: yaml2obj %p/Inputs/reloc.obj.yaml > %t.obj
 #
 # RUN: llvm-objdump -d %t.obj | FileCheck -check-prefix=BEFORE %s
 #
@@ -7,22 +7,34 @@
 
 BEFORE: Disassembly of section .text:
 BEFORE: _main:
-BEFORE:        0:       b8 00 00 00 00
-BEFORE:        5:       50
-BEFORE:        6:       68 00 00 00 00
-BEFORE:        b:       68 00 00 00 00
-BEFORE:       10:       50
-BEFORE:       11:       e8 00 00 00 00
-BEFORE:       16:       50
-BEFORE:       17:       e8 00 00 00 00
+BEFORE:       0:	55
+BEFORE:       1:	89 e5
+BEFORE:       3:	83 ec 14
+BEFORE:       6:	c7 45 fc 00 00 00 00
+BEFORE:       d:	c7 44 24 0c 00 00 00 00
+BEFORE:      15:	c7 44 24 08 07 00 00 00
+BEFORE:      1d:	c7 44 24 04 00 00 00 00
+BEFORE:      25:	c7 04 24 00 00 00 00
+BEFORE:      2c:	ff 15 00 00 00 00
+BEFORE:      32:	83 ec 10
+BEFORE:      35:	31 c0
+BEFORE:      37:	83 c4 14
+BEFORE:      3a:	5d
+BEFORE:      3b:	c3
 
 AFTER: Disassembly of section .text:
 AFTER: .text:
-AFTER:     1000:       b8 00 00 00 00
-AFTER:     1005:       50
-AFTER:     1006:       68 00 20 40 00
-AFTER:     100b:       68 06 20 40 00
-AFTER:     1010:       50
-AFTER:     1011:       e8 ea ef ff ff
-AFTER:     1016:       50
-AFTER:     1017:       e8 e4 ef ff ff
+AFTER:    1000:	55
+AFTER:    1001:	89 e5
+AFTER:    1003:	83 ec 14
+AFTER:    1006:	c7 45 fc 00 00 00 00
+AFTER:    100d:	c7 44 24 0c 00 00 00 00
+AFTER:    1015:	c7 44 24 08 07 20 40 00
+AFTER:    101d:	c7 44 24 04 00 20 40 00
+AFTER:    1025:	c7 04 24 00 00 00 00
+AFTER:    102c:	ff 15 00 00 40 00
+AFTER:    1032:	83 ec 10
+AFTER:    1035:	31 c0
+AFTER:    1037:	83 c4 14
+AFTER:    103a:	5d
+AFTER:    103b:	c3
-- 
2.7.4