From 5f8c2edef355e05c2041eba69b482f13a358abf6 Mon Sep 17 00:00:00 2001
From: Sam Clegg <sbc@chromium.org>
Date: Tue, 7 May 2019 03:53:16 +0000
Subject: [PATCH] [WebAssembly] Add more test coverage for reloctions against
 section symbols

The only known user of this relocation type and symbol type is
the debug info sections, but we were not testing the `--relocatable`
output path.

This change adds a minimal test case to cover relocations against
section symbols includes `--relocatable` output.

Differential Revision: https://reviews.llvm.org/D61623

llvm-svn: 360110
---
 lld/test/wasm/section-symbol-relocs.yaml | 51 ++++++++++++++++++++++++
 llvm/lib/ObjectYAML/WasmYAML.cpp         |  3 +-
 llvm/tools/yaml2obj/yaml2wasm.cpp        |  5 ---
 3 files changed, 53 insertions(+), 6 deletions(-)
 create mode 100644 lld/test/wasm/section-symbol-relocs.yaml

diff --git a/lld/test/wasm/section-symbol-relocs.yaml b/lld/test/wasm/section-symbol-relocs.yaml
new file mode 100644
index 000000000000..ad292e39f99e
--- /dev/null
+++ b/lld/test/wasm/section-symbol-relocs.yaml
@@ -0,0 +1,51 @@
+# RUN: yaml2obj %s -o %t.o
+# RUN: llc -filetype=obj  %S/Inputs/custom.ll -o %t2.o
+# RUN: wasm-ld --no-entry -o - %t2.o %t.o | obj2yaml | FileCheck %s
+# RUN: wasm-ld -r --no-entry -o - %t2.o %t.o | obj2yaml | FileCheck %s -check-prefix=RELOC
+
+--- !WASM
+FileHeader:
+  Version:         0x00000001
+Sections:
+  - Type:            CUSTOM
+    Name:            green
+    Payload:         'AA0000000000000000'
+    Relocations:
+      - Type:            R_WASM_SECTION_OFFSET_I32
+        Index:           0
+        Offset:          0x00000001
+      - Type:            R_WASM_SECTION_OFFSET_I32
+        Index:           1
+        Offset:          0x00000005
+  - Type:            CUSTOM
+    Name:            red
+    Payload:         'BB0000000000000000'
+  - Type:            CUSTOM
+    Name:            linking
+    Version:         2
+    SymbolTable:
+      - Index:           0
+        Kind:            SECTION
+        Section:         0
+        Flags:           [ BINDING_LOCAL ]
+      - Index:           1
+        Kind:            SECTION
+        Section:         1
+        Flags:           [ BINDING_LOCAL ]
+...
+
+# CHECK:        Name:            green
+# CHECK-NEXT:   Payload:         626172717578AA0600000003000000
+# CHECK:        Name:            red
+# CHECK-NEXT:   Payload:         666F6FBB0000000000000000
+
+# RELOC:        Relocations:
+# RELOC-NEXT:       - Type:            R_WASM_SECTION_OFFSET_I32
+# RELOC-NEXT:         Index:           0
+# RELOC-NEXT:         Offset:          0x00000007
+# RELOC-NEXT:         Addend:          6
+# RELOC-NEXT:       - Type:            R_WASM_SECTION_OFFSET_I32
+# RELOC-NEXT:         Index:           1
+# RELOC-NEXT:         Offset:          0x0000000B
+# RELOC-NEXT:         Addend:          3
+# RELOC-NEXT:    Name:            green
diff --git a/llvm/lib/ObjectYAML/WasmYAML.cpp b/llvm/lib/ObjectYAML/WasmYAML.cpp
index 214aa1c78082..88491d955c49 100644
--- a/llvm/lib/ObjectYAML/WasmYAML.cpp
+++ b/llvm/lib/ObjectYAML/WasmYAML.cpp
@@ -484,7 +484,8 @@ void MappingTraits<WasmYAML::SymbolInfo>::mapping(IO &IO,
                                                   WasmYAML::SymbolInfo &Info) {
   IO.mapRequired("Index", Info.Index);
   IO.mapRequired("Kind", Info.Kind);
-  IO.mapRequired("Name", Info.Name);
+  if (Info.Kind != wasm::WASM_SYMBOL_TYPE_SECTION)
+    IO.mapRequired("Name", Info.Name);
   IO.mapRequired("Flags", Info.Flags);
   if (Info.Kind == wasm::WASM_SYMBOL_TYPE_FUNCTION) {
     IO.mapRequired("Function", Info.ElementIndex);
diff --git a/llvm/tools/yaml2obj/yaml2wasm.cpp b/llvm/tools/yaml2obj/yaml2wasm.cpp
index cd07a30b7487..758c498bd35e 100644
--- a/llvm/tools/yaml2obj/yaml2wasm.cpp
+++ b/llvm/tools/yaml2obj/yaml2wasm.cpp
@@ -532,11 +532,6 @@ int WasmWriter::writeRelocSection(raw_ostream &OS, WasmYAML::Section &Sec,
     break;
   case wasm::WASM_SEC_CUSTOM: {
     auto CustomSection = dyn_cast<WasmYAML::CustomSection>(&Sec);
-    if (!CustomSection->Name.startswith(".debug_")) {
-      llvm_unreachable("not yet implemented (only for debug sections)");
-      return 1;
-    }
-
     writeStringRef(("reloc." + CustomSection->Name).str(), OS);
     break;
   }