[lld] r225057 - ReaderWriter: teach the writer about IMAGE_REL_ARM_ADDR32

[Saleem Abdulrasool]

Author: compnerd
Date: Wed Dec 31 21:11:53 2014
New Revision: 225057

URL: http://llvm.org/viewvc/llvm-project?rev=225057&view=rev
Log:
ReaderWriter: teach the writer about IMAGE_REL_ARM_ADDR32

This implements the IMAGE_REL_ARM_ADDR32 relocation.  There are still a few more
relocation types that need to resolved before lld can even attempt to link a
trivial program for Windows on ARM.

Added:
    lld/trunk/test/pecoff/Inputs/armnt-addr32.obj.yaml
    lld/trunk/test/pecoff/Inputs/armnt-addr32.s
    lld/trunk/test/pecoff/armnt-addr32.test
Modified:
    lld/trunk/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp

Modified: lld/trunk/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp?rev=225057&r1=225056&r2=225057&view=diff
==============================================================================
--- lld/trunk/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp (original)
+++ lld/trunk/lib/ReaderWriter/PECOFF/WriterPECOFF.cpp Wed Dec 31 21:11:53 2014
@@ -547,10 +547,31 @@ static uint32_t getSectionStartAddr(uint
   llvm_unreachable("Section missing");
 }
 
-void AtomChunk::applyRelocationsARM(uint8_t *buffer,
-                                    std::map<const Atom *, uint64_t> &atomRva,
-                                    std::vector<uint64_t> &sectionRva,
-                                    uint64_t imageBaseAddress) {
+void AtomChunk::applyRelocationsARM(uint8_t *Buffer,
+                                    std::map<const Atom *, uint64_t> &AtomRVA,
+                                    std::vector<uint64_t> &SectionRVA,
+                                    uint64_t ImageBase) {
+  Buffer = Buffer + _fileOffset;
+  for (const auto *Layout : _atomLayouts) {
+    const DefinedAtom *Atom = cast<DefinedAtom>(Layout->_atom);
+    for (const Reference *R : *Atom) {
+      if (R->kindNamespace() != Reference::KindNamespace::COFF)
+        continue;
+
+      const auto AtomOffset = R->offsetInAtom();
+      const auto FileOffset = Layout->_fileOffset;
+      const auto TargetAddr = AtomRVA[R->target()];
+      auto RelocSite32 =
+          reinterpret_cast<ulittle32_t *>(Buffer + FileOffset + AtomOffset);
+
+      switch (R->kindValue()) {
+      default: llvm_unreachable("unsupported relocation type");
+      case llvm::COFF::IMAGE_REL_ARM_ADDR32:
+        *RelocSite32 = *RelocSite32 + TargetAddr + ImageBase;
+        break;
+      }
+    }
+  }
 }
 
 void AtomChunk::applyRelocationsX86(uint8_t *buffer,

Added: lld/trunk/test/pecoff/Inputs/armnt-addr32.obj.yaml
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/pecoff/Inputs/armnt-addr32.obj.yaml?rev=225057&view=auto
==============================================================================
--- lld/trunk/test/pecoff/Inputs/armnt-addr32.obj.yaml (added)
+++ lld/trunk/test/pecoff/Inputs/armnt-addr32.obj.yaml Wed Dec 31 21:11:53 2014
@@ -0,0 +1,39 @@
+---
+header:
+  Machine:         IMAGE_FILE_MACHINE_ARMNT
+  Characteristics: [  ]
+sections:
+  - Name:            .rdata
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ ]
+    Alignment:       4
+    SectionData:     '0000000000000000'
+    Relocations:
+      - VirtualAddress:  4
+        SymbolName:      i
+        Type:            1
+symbols:
+  - Name:            .rdata
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          8
+      NumberOfRelocations: 1
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          1
+  - Name:            i
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            is
+    Value:           4
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+...

Added: lld/trunk/test/pecoff/Inputs/armnt-addr32.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/pecoff/Inputs/armnt-addr32.s?rev=225057&view=auto
==============================================================================
--- lld/trunk/test/pecoff/Inputs/armnt-addr32.s (added)
+++ lld/trunk/test/pecoff/Inputs/armnt-addr32.s Wed Dec 31 21:11:53 2014
@@ -0,0 +1,18 @@
+
+@ static const int i = 0;
+@ const int * const is[] = { &i, };
+
+	.syntax unified
+	.thumb
+	.text
+
+	.section .rdata,"rd"
+	.align 2	# @i
+i:
+	.long 0		# 0x0
+
+	.global is	# @is
+	.align 2
+is:
+	.long i
+

Added: lld/trunk/test/pecoff/armnt-addr32.test
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/pecoff/armnt-addr32.test?rev=225057&view=auto
==============================================================================
--- lld/trunk/test/pecoff/armnt-addr32.test (added)
+++ lld/trunk/test/pecoff/armnt-addr32.test Wed Dec 31 21:11:53 2014
@@ -0,0 +1,11 @@
+# RUN: yaml2obj -format coff -o %t.obj %p/Inputs/armnt-addr32.obj.yaml
+# RUN: llvm-objdump -s %t.obj | FileCheck %s -check-prefix BEFORE
+# RUN: lld -flavor link /entry:is /subsystem:console /out:%t.exe %t.obj
+# RUN: llvm-objdump -s %t.exe | FileCheck %s -check-prefix AFTER
+
+BEFORE: Contents of section .rdata:
+BEFORE:  0000 00000000 00000000
+
+AFTER: Contents of section .rdata:
+AFTER:  1000 00000000 00104000
+