[WebAssembly] Base imports on Symtab. NFC.

Since imports are undefined symbols we know we can
find all of them my looking at the symbol table alone.
(i.e. imports cannot be have local binding).

This will be strictly faster and also allows us
to to remove a method from Symbol class

Differential Revision: https://reviews.llvm.org/D41304

llvm-svn: 320847

2 files changed, 9 insertions, 14 deletions

diff --git a/lld/wasm/Symbols.h b/lld/wasm/Symbols.h
index 744d8a95c6c..8194bcaca38 100644
--- a/lld/wasm/Symbols.h
+++ b/lld/wasm/Symbols.h
@@ -78,9 +78,6 @@ public:
   // Only works for globals, not functions.
   uint32_t getVirtualAddress() const;
 
-  // Returns true if an output index has been set for this symbol
-  bool hasOutputIndex() const { return OutputIndex.hasValue(); }
-
   // Set the output index of the symbol (in the function or global index
   // space of the output object.
   void setOutputIndex(uint32_t Index);
diff --git a/lld/wasm/Writer.cpp b/lld/wasm/Writer.cpp
index 4d9d9239adc..82197547523 100644
--- a/lld/wasm/Writer.cpp
+++ b/lld/wasm/Writer.cpp
@@ -550,18 +550,16 @@ void Writer::calculateOffsets() {
 }
 
 void Writer::calculateImports() {
-  for (ObjFile *File : Symtab->ObjectFiles) {
-    for (Symbol *Sym : File->getSymbols()) {
-      if (Sym->hasOutputIndex() || Sym->isDefined() || Sym->isWeak())
-        continue;
+  for (Symbol *Sym : Symtab->getSymbols()) {
+    if (Sym->isDefined() || Sym->isWeak())
+      continue;
 
-      if (Sym->isFunction()) {
-        Sym->setOutputIndex(FunctionImports.size());
-        FunctionImports.push_back(Sym);
-      } else {
-        Sym->setOutputIndex(GlobalImports.size());
-        GlobalImports.push_back(Sym);
-      }
+    if (Sym->isFunction()) {
+      Sym->setOutputIndex(FunctionImports.size());
+      FunctionImports.push_back(Sym);
+    } else {
+      Sym->setOutputIndex(GlobalImports.size());
+      GlobalImports.push_back(Sym);
     }
   }
 }