From 3a8fe655a52a109791167c22fd8feee0500c11a7 Mon Sep 17 00:00:00 2001
From: Sam Clegg <sbc@chromium.org>
Date: Mon, 26 Jun 2017 21:01:39 +0000
Subject: [PATCH] [WebAssembly] Add more support for weak symbols

Add weak symbol tests to MC
Add symbol flags to output of `llvm-readobj -t`.

Differential Revision: https://reviews.llvm.org/D34635

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306330 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/MC/WebAssembly/weak-alias.ll    | 33 +++++++++++++++++++++++++++
 test/MC/WebAssembly/weak.ll          | 34 ++++++++++++++++++++++++++++
 test/tools/llvm-readobj/symbols.test |  4 ++++
 tools/llvm-readobj/WasmDumper.cpp    |  1 +
 4 files changed, 72 insertions(+)
 create mode 100644 test/MC/WebAssembly/weak-alias.ll
 create mode 100644 test/MC/WebAssembly/weak.ll

diff --git a/test/MC/WebAssembly/weak-alias.ll b/test/MC/WebAssembly/weak-alias.ll
new file mode 100644
index 00000000000..9e4cc4e587d
--- /dev/null
+++ b/test/MC/WebAssembly/weak-alias.ll
@@ -0,0 +1,33 @@
+; RUN: llc -mtriple wasm32-unknown-unknown-wasm -filetype=obj %s -o - | obj2yaml | FileCheck %s
+
+; foo_alias() function is weak alias of function foo()
+; Generates two exports of the same function, one of them weak
+
+@foo_alias = weak hidden alias i32 (...), bitcast (i32 ()* @foo to i32 (...)*)
+
+define hidden i32 @foo() #0 {
+entry:
+  ret i32 0
+}
+
+; CHECK:        - Type:            EXPORT
+; CHECK-NEXT:     Exports:         
+; CHECK-NEXT:       - Name:            foo
+; CHECK-NEXT:         Kind:            FUNCTION
+; CHECK-NEXT:         Index:           0
+; CHECK-NEXT:       - Name:            foo_alias
+; CHECK-NEXT:         Kind:            FUNCTION
+; CHECK-NEXT:         Index:           0
+
+
+; CHECK:        - Type:            CUSTOM
+; CHECK-NEXT:     Name:            name
+; CHECK-NEXT:     FunctionNames:   
+; CHECK-NEXT:       - Index:           0
+; CHECK-NEXT:         Name:            foo
+; CHECK-NEXT:   - Type:            CUSTOM
+; CHECK-NEXT:     Name:            linking
+; CHECK-NEXT:     SymbolInfo:      
+; CHECK-NEXT:       - Name:            foo_alias
+; CHECK-NEXT:         Flags:           1
+; CHECK-NEXT: ...
diff --git a/test/MC/WebAssembly/weak.ll b/test/MC/WebAssembly/weak.ll
new file mode 100644
index 00000000000..73d40afbd98
--- /dev/null
+++ b/test/MC/WebAssembly/weak.ll
@@ -0,0 +1,34 @@
+; RUN: llc -mtriple wasm32-unknown-unknown-wasm -filetype=obj %s -o - | obj2yaml | FileCheck %s
+
+; Weak external data reference
+@weak_external_data = extern_weak global i32, align 4
+
+; Weak function definition
+define weak hidden i32 @weak_function() local_unnamed_addr #0 {
+entry:
+    %0 = load i32, i32* @weak_external_data, align 4
+    ret i32 %0
+}
+
+; CHECK:        - Type:            IMPORT
+; CHECK-NEXT:     Imports:         
+; CHECK-NEXT:       - Module:          env
+; CHECK-NEXT:         Field:           weak_external_data
+; CHECK-NEXT:         Kind:            GLOBAL
+; CHECK-NEXT:         GlobalType:      I32
+; CHECK-NEXT:         GlobalMutable:   false
+
+
+; CHECK:        - Type:            CUSTOM
+; CHECK-NEXT:     Name:            name
+; CHECK-NEXT:     FunctionNames:   
+; CHECK-NEXT:       - Index:           0
+; CHECK-NEXT:         Name:            weak_function
+; CHECK-NEXT:   - Type:            CUSTOM
+; CHECK-NEXT:     Name:            linking
+; CHECK-NEXT:     SymbolInfo:      
+; CHECK-NEXT:       - Name:            weak_external_data
+; CHECK-NEXT:         Flags:           1
+; CHECK-NEXT:       - Name:            weak_function
+; CHECK-NEXT:         Flags:           1
+; CHECK-NEXT: ...
diff --git a/test/tools/llvm-readobj/symbols.test b/test/tools/llvm-readobj/symbols.test
index 1037c286602..da8a70b031a 100644
--- a/test/tools/llvm-readobj/symbols.test
+++ b/test/tools/llvm-readobj/symbols.test
@@ -75,17 +75,21 @@ WASM:      Symbols [
 WASM-NEXT:   Symbol {
 WASM-NEXT:     Name: bar
 WASM-NEXT:     Type: GLOBAL_IMPORT (0x2)
+WASM-NEXT:     Flags: 0x0
 WASM-NEXT:   }
 WASM-NEXT:   Symbol {
 WASM-NEXT:     Name: baz
 WASM-NEXT:     Type: GLOBAL_IMPORT (0x2)
+WASM-NEXT:     Flags: 0x0
 WASM-NEXT:   }
 WASM-NEXT:   Symbol {
 WASM-NEXT:     Name: foo
 WASM-NEXT:     Type: FUNCTION_EXPORT (0x1)
+WASM-NEXT:     Flags: 0x0
 WASM-NEXT:   }
 WASM-NEXT:   Symbol {
 WASM-NEXT:     Name: foo
 WASM-NEXT:     Type: DEBUG_FUNCTION_NAME (0x4)
+WASM-NEXT:     Flags: 0x0
 WASM-NEXT:   }
 WASM-NEXT: ]
diff --git a/tools/llvm-readobj/WasmDumper.cpp b/tools/llvm-readobj/WasmDumper.cpp
index 21614297e46..14603f8a2b0 100644
--- a/tools/llvm-readobj/WasmDumper.cpp
+++ b/tools/llvm-readobj/WasmDumper.cpp
@@ -183,6 +183,7 @@ void WasmDumper::printSymbol(const SymbolRef &Sym) {
   WasmSymbol Symbol = Obj->getWasmSymbol(Sym.getRawDataRefImpl());
   W.printString("Name", Symbol.Name);
   W.printEnum("Type", static_cast<unsigned>(Symbol.Type), makeArrayRef(WasmSymbolTypes));
+  W.printHex("Flags", Symbol.Flags);
 }
 
 }
-- 
2.50.1