[WebAssembly] Fix getSymbolValue for exported globals

The code wasn't previously taking into account that the
global index space is not same as the into in the Globals
array since the latter does not include imported globals.

This fixes the WebAssembly waterfall failures.

Differential Revision: https://reviews.llvm.org/D37384

llvm-svn: 312340

4 files changed, 21 insertions, 8 deletions

diff --git a/llvm/lib/Object/WasmObjectFile.cpp b/llvm/lib/Object/WasmObjectFile.cpp
index ad8c2b706de..e1bab727f17 100644
--- a/llvm/lib/Object/WasmObjectFile.cpp
+++ b/llvm/lib/Object/WasmObjectFile.cpp
@@ -788,7 +788,7 @@ uint64_t WasmObjectFile::getSymbolValueImpl(DataRefImpl Symb) const {
   case WasmSymbol::SymbolType::FUNCTION_EXPORT:
     return Exports[Sym.ElementIndex].Index;
   case WasmSymbol::SymbolType::GLOBAL_EXPORT: {
-    uint32_t GlobalIndex = Exports[Sym.ElementIndex].Index;
+    uint32_t GlobalIndex = Exports[Sym.ElementIndex].Index - NumImportedGlobals;
     assert(GlobalIndex < Globals.size());
     const wasm::WasmGlobal& Global = Globals[GlobalIndex];
     return Global.InitExpr.Value.Int32;
diff --git a/llvm/test/tools/llvm-nm/wasm/exports.yaml b/llvm/test/tools/llvm-nm/wasm/exports.yaml
index 420cc2f5dbb..953d17f6ad7 100644
--- a/llvm/test/tools/llvm-nm/wasm/exports.yaml
+++ b/llvm/test/tools/llvm-nm/wasm/exports.yaml
@@ -1,4 +1,4 @@
-# RUN: yaml2obj < %s | llvm-nm - | FileCheck %s
+# RUN: yaml2obj < %s | llvm-nm - | FileCheck -strict-whitespace %s
 
 # That wasm exports of functions and globals are displayed as global data and
 # code symbols.
@@ -31,6 +31,17 @@ Sections:
         InitExpr:
           Opcode:          I64_CONST
           Value:           1024
+  - Type:            IMPORT
+    Imports:
+      - Module:          env
+        Field:           fimport
+        Kind:            FUNCTION
+        SigIndex:        0
+      - Module:          env
+        Field:           gimport
+        Kind:            GLOBAL
+        GlobalType:      I32
+        GlobalMutable:   false
   - Type:            EXPORT
     Exports:
       - Name:            foo
@@ -38,7 +49,9 @@ Sections:
         Index:           0x00000004
       - Name:            bar
         Kind:            GLOBAL
-        Index:           0x00000002
+        Index:           0x00000003
 
-# CHECK: 00000400 D bar
-# CHECK: 00000004 T foo
+# CHECK:      00000400 D bar
+# CHECK-NEXT:          U fimport
+# CHECK-NEXT: 00000004 T foo
+# CHECK-NEXT:          U gimport
diff --git a/llvm/test/tools/llvm-nm/wasm/imports.yaml b/llvm/test/tools/llvm-nm/wasm/imports.yaml
index 3842d678ca7..5122c2cae77 100644
--- a/llvm/test/tools/llvm-nm/wasm/imports.yaml
+++ b/llvm/test/tools/llvm-nm/wasm/imports.yaml
@@ -1,4 +1,4 @@
-# RUN: yaml2obj < %s | llvm-nm - | FileCheck %s
+# RUN: yaml2obj < %s | llvm-nm - | FileCheck -strict-whitespace %s
 
 --- !WASM
 FileHeader:
diff --git a/llvm/test/tools/llvm-nm/wasm/weak-symbols.yaml b/llvm/test/tools/llvm-nm/wasm/weak-symbols.yaml
index 91c4dd6262a..8f0b47f6239 100644
--- a/llvm/test/tools/llvm-nm/wasm/weak-symbols.yaml
+++ b/llvm/test/tools/llvm-nm/wasm/weak-symbols.yaml
@@ -1,4 +1,4 @@
-# RUN: yaml2obj < %s | llvm-nm - | FileCheck %s
+# RUN: yaml2obj < %s | llvm-nm - | FileCheck -strict-whitespace %s
 
 # That wasm exports of functions and globals are displayed as global data and
 # code symbols.
@@ -49,7 +49,7 @@ Sections:
         Index:           0x00000004
       - Name:            weak_global_data
         Kind:            GLOBAL
-        Index:           0x00000002
+        Index:           0x00000003
   - Type:            CUSTOM
     Name:            linking
     DataSize:        0