[llvm] r227261 - SymbolRewriter: allow rewriting with comdats

[Saleem Abdulrasool]

Author: compnerd
Date: Tue Jan 27 16:57:39 2015
New Revision: 227261

URL: http://llvm.org/viewvc/llvm-project?rev=227261&view=rev
Log:
SymbolRewriter: allow rewriting with comdats

COMDATs must be identically named to the symbol.  When support for COMDATs was
introduced, the symbol rewriter was not updated, resulting in rewriting failing
for symbols which were placed into COMDATs.  This corrects the behaviour and
adds test cases for this.

Modified:
    llvm/trunk/lib/Transforms/Utils/SymbolRewriter.cpp
    llvm/trunk/test/SymbolRewriter/rewrite.ll
    llvm/trunk/test/SymbolRewriter/rewrite.map

Modified: llvm/trunk/lib/Transforms/Utils/SymbolRewriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SymbolRewriter.cpp?rev=227261&r1=227260&r2=227261&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/SymbolRewriter.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/SymbolRewriter.cpp Tue Jan 27 16:57:39 2015
@@ -79,6 +79,19 @@ static cl::list<std::string> RewriteMapF
 
 namespace llvm {
 namespace SymbolRewriter {
+void rewriteComdat(Module &M, GlobalObject *GO, const std::string &Source,
+                   const std::string &Target) {
+  if (Comdat *CD = GO->getComdat()) {
+    auto &Comdats = M.getComdatSymbolTable();
+
+    Comdat *C = M.getOrInsertComdat(Target);
+    C->setSelectionKind(CD->getSelectionKind());
+    GO->setComdat(C);
+
+    Comdats.erase(Comdats.find(Source));
+  }
+}
+
 template <RewriteDescriptor::Type DT, typename ValueType,
           ValueType *(llvm::Module::*Get)(StringRef) const>
 class ExplicitRewriteDescriptor : public RewriteDescriptor {
@@ -102,10 +115,14 @@ template <RewriteDescriptor::Type DT, ty
 bool ExplicitRewriteDescriptor<DT, ValueType, Get>::performOnModule(Module &M) {
   bool Changed = false;
   if (ValueType *S = (M.*Get)(Source)) {
+    if (GlobalObject *GO = dyn_cast<GlobalObject>(S))
+      rewriteComdat(M, GO, Source, Target);
+
     if (Value *T = (M.*Get)(Target))
       S->setValueName(T->getValueName());
     else
       S->setName(Target);
+
     Changed = true;
   }
   return Changed;
@@ -148,6 +165,9 @@ performOnModule(Module &M) {
     if (C.getName() == Name)
       continue;
 
+    if (GlobalObject *GO = dyn_cast<GlobalObject>(&C))
+      rewriteComdat(M, GO, C.getName(), Name);
+
     if (Value *V = (M.*Get)(Name))
       C.setValueName(V->getValueName());
     else

Modified: llvm/trunk/test/SymbolRewriter/rewrite.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/SymbolRewriter/rewrite.ll?rev=227261&r1=227260&r2=227261&view=diff
==============================================================================
--- llvm/trunk/test/SymbolRewriter/rewrite.ll (original)
+++ llvm/trunk/test/SymbolRewriter/rewrite.ll Tue Jan 27 16:57:39 2015
@@ -28,12 +28,40 @@ entry:
   ret void
 }
 
+$source_comdat_function = comdat any
+define dllexport void @source_comdat_function() comdat($source_comdat_function) {
+entry:
+  ret void
+}
+
+$source_comdat_function_1 = comdat exactmatch
+define dllexport void @source_comdat_function_1() comdat($source_comdat_function_1) {
+entry:
+  ret void
+}
+
+$source_comdat_variable = comdat largest
+ at source_comdat_variable = global i32 32, comdat($source_comdat_variable)
+
+$source_comdat_variable_1 = comdat noduplicates
+ at source_comdat_variable_1 = global i32 64, comdat($source_comdat_variable_1)
+
+; CHECK: $target_comdat_function = comdat any
+; CHECK: $target_comdat_function_1 = comdat exactmatch
+; CHECK: $target_comdat_variable = comdat largest
+; CHECK: $target_comdat_variable_1 = comdat noduplicates
+
 ; CHECK: @target_variable = external global i32
 ; CHECK-NOT: @source_variable = external global i32
 ; CHECK: @target_pattern_variable = external global i32
 ; CHECK-NOT: @source_pattern_variable = external global i32
 ; CHECK: @target_pattern_multiple_variable_matches = external global i32
 ; CHECK-NOT: @source_pattern_multiple_variable_matches = external global i32
+; CHECK: @target_comdat_variable = global i32 32, comdat
+; CHECK-NOT: @source_comdat_variable = global i32 32, comdat
+; CHECK: @target_comdat_variable_1 = global i32 64, comdat
+; CHECK-NOT: @source_comdat_variable_1 = global i32 64, comdat
+
 ; CHECK: declare void @target_function()
 ; CHECK-NOT: declare void @source_function()
 ; CHECK: declare void @target_pattern_function()
@@ -57,3 +85,8 @@ entry:
 ; CHECK:   ret i32 %res
 ; CHECK: }
 
+; CHECK: define dllexport void @target_comdat_function() comdat
+; CHECK-NOT: define dllexport void @source_comdat_function() comdat
+; CHECK: define dllexport void @target_comdat_function_1() comdat
+; CHECK-NOT: define dllexport void @source_comdat_function_1() comdat
+

Modified: llvm/trunk/test/SymbolRewriter/rewrite.map
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/SymbolRewriter/rewrite.map?rev=227261&r1=227260&r2=227261&view=diff
==============================================================================
--- llvm/trunk/test/SymbolRewriter/rewrite.map (original)
+++ llvm/trunk/test/SymbolRewriter/rewrite.map Tue Jan 27 16:57:39 2015
@@ -44,3 +44,23 @@ global alias: {
   target: _ZN1SD1Ev,
 }
 
+function: {
+  source: source_comdat_function,
+  target: target_comdat_function,
+}
+
+function: {
+  source: source_comdat_function_(.*),
+  transform: target_comdat_function_\1,
+}
+
+global variable: {
+  source: source_comdat_variable,
+  target: target_comdat_variable,
+}
+
+global variable: {
+  source: source_comdat_variable_(.*),
+  transform: target_comdat_variable_\1,
+}
+