[COFF] Correctly set the thumb bit in DLL export addresses

The same adjustment is already done for the entry point in
Writer.cpp and for relocations that point to executable code
in Chunks.cpp.

Differential Revision: https://reviews.llvm.org/D35767

llvm-svn: 308953

2 files changed, 78 insertions, 2 deletions

diff --git a/lld/COFF/DLL.cpp b/lld/COFF/DLL.cpp
index 1fdb40a913c..55fd2b50d06 100644
--- a/lld/COFF/DLL.cpp
+++ b/lld/COFF/DLL.cpp
@@ -319,12 +319,16 @@ public:
   size_t getSize() const override { return Size * 4; }
 
   void writeTo(uint8_t *Buf) const override {
+    uint32_t Bit = 0;
+    // Pointer to thumb code must have the LSB set, so adjust it.
+    if (Config->Machine == ARMNT)
+      Bit = 1;
     for (Export &E : Config->Exports) {
       uint8_t *P = Buf + OutputSectionOff + E.Ordinal * 4;
       if (E.ForwardChunk) {
-        write32le(P, E.ForwardChunk->getRVA());
+        write32le(P, E.ForwardChunk->getRVA() | Bit);
       } else {
-        write32le(P, cast<Defined>(E.Sym)->getRVA());
+        write32le(P, cast<Defined>(E.Sym)->getRVA() | Bit);
       }
     }
   }
diff --git a/lld/test/COFF/export-armnt.yaml b/lld/test/COFF/export-armnt.yaml
new file mode 100644
index 00000000000..461d5a033fe
--- /dev/null
+++ b/lld/test/COFF/export-armnt.yaml
@@ -0,0 +1,72 @@
+# REQUIRES: arm
+
+# RUN: yaml2obj < %s > %t.obj
+#
+# RUN: lld-link /out:%t.dll /dll %t.obj /export:exportfn1 /export:exportfn2
+# RUN: llvm-objdump -p %t.dll | FileCheck %s
+
+# CHECK:      Export Table:
+# CHECK:      DLL name: export-armnt.yaml.tmp.dll
+# CHECK:      Ordinal      RVA  Name
+# CHECK-NEXT:       0        0
+# CHECK-NEXT:       1   0x1005  exportfn1
+# CHECK-NEXT:       2   0x1009  exportfn2
+# CHECK-NEXT:       3   0x1009  exportfn3
+
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_ARMNT
+  Characteristics: []
+sections:
+  - Name:            .text
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       4
+    SectionData:     704700bf704700bf704700bf
+  - Name:            .drectve
+    Characteristics: [ IMAGE_SCN_LNK_INFO, IMAGE_SCN_LNK_REMOVE ]
+    Alignment:       1
+    SectionData:     2f6578706f72743a6578706f7274666e3300  # /export:exportfn3
+symbols:
+  - Name:            .text
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          12
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            _DllMainCRTStartup
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            exportfn1
+    Value:           4
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            exportfn2
+    Value:           8
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            exportfn3
+    Value:           8
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            '?mangled@@YAHXZ'
+    Value:           8
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...