[llvm] r354694 - [WebAssembly] MC: Handle aliases of aliases

[Sam Clegg via llvm-commits]

Author: sbc
Date: Fri Feb 22 13:41:42 2019
New Revision: 354694

URL: http://llvm.org/viewvc/llvm-project?rev=354694&view=rev
Log:
[WebAssembly] MC: Handle aliases of aliases

Differential Revision: https://reviews.llvm.org/D58417

Modified:
    llvm/trunk/lib/MC/WasmObjectWriter.cpp
    llvm/trunk/test/MC/WebAssembly/function-alias.ll

Modified: llvm/trunk/lib/MC/WasmObjectWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/WasmObjectWriter.cpp?rev=354694&r1=354693&r2=354694&view=diff
==============================================================================
--- llvm/trunk/lib/MC/WasmObjectWriter.cpp (original)
+++ llvm/trunk/lib/MC/WasmObjectWriter.cpp Fri Feb 22 13:41:42 2019
@@ -558,12 +558,13 @@ void WasmObjectWriter::recordRelocation(
 }
 
 static const MCSymbolWasm *resolveSymbol(const MCSymbolWasm &Symbol) {
-  if (Symbol.isVariable()) {
-    const MCExpr *Expr = Symbol.getVariableValue();
+  const MCSymbolWasm* Ret = &Symbol;
+  while (Ret->isVariable()) {
+    const MCExpr *Expr = Ret->getVariableValue();
     auto *Inner = cast<MCSymbolRefExpr>(Expr);
-    return cast<MCSymbolWasm>(&Inner->getSymbol());
+    Ret = cast<MCSymbolWasm>(&Inner->getSymbol());
   }
-  return &Symbol;
+  return Ret;
 }
 
 // Compute a value to write into the code at the location covered
@@ -1422,12 +1423,12 @@ uint64_t WasmObjectWriter::writeObject(M
     LLVM_DEBUG(dbgs() << WS.getName() << ": weak alias of '" << *ResolvedSym
                       << "'\n");
 
-    if (WS.isFunction()) {
+    if (ResolvedSym->isFunction()) {
       assert(WasmIndices.count(ResolvedSym) > 0);
       uint32_t WasmIndex = WasmIndices.find(ResolvedSym)->second;
       WasmIndices[&WS] = WasmIndex;
       LLVM_DEBUG(dbgs() << "  -> index:" << WasmIndex << "\n");
-    } else if (WS.isData()) {
+    } else if (ResolvedSym->isData()) {
       assert(DataLocations.count(ResolvedSym) > 0);
       const wasm::WasmDataReference &Ref =
           DataLocations.find(ResolvedSym)->second;

Modified: llvm/trunk/test/MC/WebAssembly/function-alias.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/WebAssembly/function-alias.ll?rev=354694&r1=354693&r2=354694&view=diff
==============================================================================
--- llvm/trunk/test/MC/WebAssembly/function-alias.ll (original)
+++ llvm/trunk/test/MC/WebAssembly/function-alias.ll Fri Feb 22 13:41:42 2019
@@ -5,8 +5,10 @@ target triple = "wasm32-unknown-unknown-
 
 @foo = alias i8, bitcast (i8* ()* @func to i8*)
 @bar = alias i8* (), i8* ()* @func
+ at bar2 = alias i8* (), i8* ()* @bar
 
 define i8* @func() {
+  call i8* @bar2();
   ret i8* @foo;
 }
 
@@ -16,6 +18,13 @@ define i8* @func() {
 ; CHECK-NEXT:     Type: FUNCTION (0x0)
 ; CHECK-NEXT:     Flags [ (0x0)
 ; CHECK-NEXT:     ]
+; CHECK-NEXT:     ElementIndex: 0x0
+; CHECK-NEXT:   }
+; CHECK-NEXT:   Symbol {
+; CHECK-NEXT:     Name: bar2
+; CHECK-NEXT:     Type: FUNCTION (0x0)
+; CHECK-NEXT:     Flags [ (0x0)
+; CHECK-NEXT:     ]
 ; CHECK-NEXT:     ElementIndex: 0x0
 ; CHECK-NEXT:   }
 ; CHECK-NEXT:   Symbol {