[ORC][COFF] Properly set weak flag to COMDAT symbols.

Properly set weak flag to COMDAT symbols so that no duplicate definition error will be generated. There is an inaccuracy in setting plain weak for largest selection type, which will be dealt with soon when largest type is properly implemented.

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D129764

diff --git a/llvm/lib/ExecutionEngine/Orc/ObjectFileInterface.cpp b/llvm/lib/ExecutionEngine/Orc/ObjectFileInterface.cpp
index 356b81b..3de15db 100644 (file)
--- a/llvm/lib/ExecutionEngine/Orc/ObjectFileInterface.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/ObjectFileInterface.cpp
@@ -150,16 +150,39 @@ static Expected<MaterializationUnit::Interface>
 getCOFFObjectFileSymbolInfo(ExecutionSession &ES,
                             const object::COFFObjectFile &Obj) {
   MaterializationUnit::Interface I;
-
+  std::vector<Optional<object::coff_aux_section_definition>> ComdatDefs(
+      Obj.getNumberOfSections() + 1);
   for (auto &Sym : Obj.symbols()) {
     Expected<uint32_t> SymFlagsOrErr = Sym.getFlags();
     if (!SymFlagsOrErr)
       // TODO: Test this error.
       return SymFlagsOrErr.takeError();
 
-    // Skip symbols not defined in this object file.
-    if (*SymFlagsOrErr & object::BasicSymbolRef::SF_Undefined)
-      continue;
+    // Handle comdat symbols
+    auto COFFSym = Obj.getCOFFSymbol(Sym);
+    bool IsWeak = false;
+    if (auto *Def = COFFSym.getSectionDefinition()) {
+      auto Sec = Obj.getSection(COFFSym.getSectionNumber());
+      if (!Sec)
+        return Sec.takeError();
+      if (((*Sec)->Characteristics & COFF::IMAGE_SCN_LNK_COMDAT) &&
+          Def->Selection != COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE) {
+        ComdatDefs[COFFSym.getSectionNumber()] = *Def;
+        continue;
+      }
+    }
+    if (!COFF::isReservedSectionNumber(COFFSym.getSectionNumber()) &&
+        ComdatDefs[COFFSym.getSectionNumber()]) {
+      auto Def = ComdatDefs[COFFSym.getSectionNumber()];
+      if (Def->Selection != COFF::IMAGE_COMDAT_SELECT_NODUPLICATES) {
+        IsWeak = true;
+      }
+      ComdatDefs[COFFSym.getSectionNumber()] = None;
+    } else {
+      // Skip symbols not defined in this object file.
+      if (*SymFlagsOrErr & object::BasicSymbolRef::SF_Undefined)
+        continue;
+    }
 
     // Skip symbols that are not global.
     if (!(*SymFlagsOrErr & object::BasicSymbolRef::SF_Global))
@@ -180,12 +203,13 @@ getCOFFObjectFileSymbolInfo(ExecutionSession &ES,
     if (!SymFlags)
       return SymFlags.takeError();
     *SymFlags |= JITSymbolFlags::Exported;
-    auto COFFSym = Obj.getCOFFSymbol(Sym);
 
     // Weak external is always a function
-    if (COFFSym.isWeakExternal()) {
+    if (COFFSym.isWeakExternal())
       *SymFlags |= JITSymbolFlags::Callable;
-    }
+
+    if (IsWeak)
+      *SymFlags |= JITSymbolFlags::Weak;
 
     I.SymbolFlags[ES.intern(*Name)] = std::move(*SymFlags);
   }

diff --git a/llvm/test/ExecutionEngine/JITLink/X86/COFF_comdat_weak_duplicate.s b/llvm/test/ExecutionEngine/JITLink/X86/COFF_comdat_weak_duplicate.s
new file mode 100644 (file)
index 0000000..6a0c001
--- /dev/null
+++ b/llvm/test/ExecutionEngine/JITLink/X86/COFF_comdat_weak_duplicate.s
@@ -0,0 +1,29 @@
+# RUN: rm -rf %t && mkdir -p %t
+# RUN: yaml2obj %S/Inputs/COFF_comdat_weak_def.yaml -o %t/COFF_weak_1.o
+# RUN: yaml2obj %S/Inputs/COFF_comdat_weak_def.yaml -o %t/COFF_weak_2.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-windows-msvc %s -o %t/COFF_main.o
+# RUN: 
+# RUN: llvm-jitlink -noexec %t/COFF_main.o %t/COFF_weak_1.o %t/COFF_weak_2.o \
+# RUN: -slab-allocate 100Kb -slab-address 0xfff00000 -slab-page-size 4096 \
+# RUN: -show-graph -noexec 2>&1 | FileCheck %s
+#
+# Check that duplicate comdat any definitions don't generate duplicate definition error.
+#
+# CHECK: section weakfunc:
+# CHECK-EMPTY:
+# CHECK-NEXT:  block 0xfff02000 size = 0x00000001, align = 16, alignment-offset = 0
+# CHECK-NEXT:    symbols:
+# CHECK-NEXT:      0xfff02000 (block + 0x00000000): size: 0x00000001, linkage: weak, scope: default, live  -   func
+# CHECK-NEXT:    no edges
+
+       .text
+
+       .def    main;
+       .scl    2;
+       .type   32;
+       .endef
+       .globl  main
+       .p2align        4, 0x90
+main:
+    callq func
+       retq
\ No newline at end of file

diff --git a/llvm/test/ExecutionEngine/JITLink/X86/COFF_comdat_weak_plus_strong.s b/llvm/test/ExecutionEngine/JITLink/X86/COFF_comdat_weak_plus_strong.s
new file mode 100644 (file)
index 0000000..30e0193
--- /dev/null
+++ b/llvm/test/ExecutionEngine/JITLink/X86/COFF_comdat_weak_plus_strong.s
@@ -0,0 +1,32 @@
+# FIXME: Comdat any + ordinary strong symbol should generate duplicate section error
+# XFAIL: *
+# RUN: rm -rf %t && mkdir -p %t
+# RUN: yaml2obj %S/Inputs/COFF_comdat_weak_def.yaml -o %t/COFF_weak_1.o
+# RUN: yaml2obj %S/Inputs/COFF_strong_def.yaml -o %t/COFF_strong.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-windows-msvc %s -o %t/COFF_main.o
+# RUN: 
+# RUN: not llvm-jitlink -noexec %t/COFF_main.o %t/COFF_weak_1.o %t/COFF_strong.o \
+# RUN: -slab-allocate 100Kb -slab-address 0xfff00000 -slab-page-size 4096 \
+# RUN: -show-graph -noexec 2>&1 | FileCheck %s
+#
+# Check that a combination of comdat any definition and strong definition generate 
+# duplicate definition error.
+#
+# CHECK: section strongfunc:
+# CHECK-EMPTY:
+# CHECK-NEXT:  block 0xfff02000 size = 0x00000001, align = 16, alignment-offset = 0
+# CHECK-NEXT:    symbols:
+# CHECK-NEXT:      0xfff02000 (block + 0x00000000): size: 0x00000001, linkage: strong, scope: default, live  -   func
+# CHECK-NEXT:    no edges
+
+       .text
+
+       .def    main;
+       .scl    2;
+       .type   32;
+       .endef
+       .globl  main
+       .p2align        4, 0x90
+main:
+    callq func
+       retq
\ No newline at end of file

diff --git a/llvm/test/ExecutionEngine/JITLink/X86/COFF_strong_duplicate.s b/llvm/test/ExecutionEngine/JITLink/X86/COFF_strong_duplicate.s
new file mode 100644 (file)
index 0000000..5ad9c68
--- /dev/null
+++ b/llvm/test/ExecutionEngine/JITLink/X86/COFF_strong_duplicate.s
@@ -0,0 +1,23 @@
+# RUN: rm -rf %t && mkdir -p %t
+# RUN: yaml2obj %S/Inputs/COFF_strong_def.yaml -o %t/COFF_strong_1.o
+# RUN: yaml2obj %S/Inputs/COFF_strong_def.yaml -o %t/COFF_strong_2.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-windows-msvc %s -o %t/COFF_main.o
+# RUN: 
+# RUN: not llvm-jitlink -noexec %t/COFF_main.o %t/COFF_strong_1.o %t/COFF_strong_2.o \
+# RUN: -slab-allocate 100Kb -slab-address 0xfff00000 -slab-page-size 4096 \
+# RUN: -show-graph
+#
+# Check that duplicate strong definitions cause llvm-jitlink to terminate with error.
+#
+
+       .text
+
+       .def    main;
+       .scl    2;
+       .type   32;
+       .endef
+       .globl  main
+       .p2align        4, 0x90
+main:
+    callq func
+       retq
\ No newline at end of file

diff --git a/llvm/test/ExecutionEngine/JITLink/X86/Inputs/COFF_comdat_weak_def.yaml b/llvm/test/ExecutionEngine/JITLink/X86/Inputs/COFF_comdat_weak_def.yaml
new file mode 100644 (file)
index 0000000..c734cb2
--- /dev/null
+++ b/llvm/test/ExecutionEngine/JITLink/X86/Inputs/COFF_comdat_weak_def.yaml
@@ -0,0 +1,30 @@
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            weakfunc
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_LNK_COMDAT, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     C3
+symbols:
+  - Name:            weakfunc
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          1
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        40735498
+      Number:          1
+      Selection:       IMAGE_COMDAT_SELECT_ANY
+  - Name:            func
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...

diff --git a/llvm/test/ExecutionEngine/JITLink/X86/Inputs/COFF_strong_def.yaml b/llvm/test/ExecutionEngine/JITLink/X86/Inputs/COFF_strong_def.yaml
new file mode 100644 (file)
index 0000000..3ba49cd
--- /dev/null
+++ b/llvm/test/ExecutionEngine/JITLink/X86/Inputs/COFF_strong_def.yaml
@@ -0,0 +1,29 @@
+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            strongfunc
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     C3
+symbols:
+  - Name:            strongfunc
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          1
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        40735498
+      Number:          1
+  - Name:            func
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...