[llvm-commits] [llvm] r44278 - in /llvm/trunk: lib/Transforms/Scalar/ADCE.cpp test/Transforms/ADCE/dce_pure_invoke.ll

[Duncan Sands]

Author: baldrick
Date: Thu Nov 22 15:40:06 2007
New Revision: 44278

URL: http://llvm.org/viewvc/llvm-project?rev=44278&view=rev
Log:
Readonly/readnone functions are allowed to throw
exceptions, so don't turn invokes of them into
calls.

Modified:
    llvm/trunk/lib/Transforms/Scalar/ADCE.cpp
    llvm/trunk/test/Transforms/ADCE/dce_pure_invoke.ll

Modified: llvm/trunk/lib/Transforms/Scalar/ADCE.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/ADCE.cpp?rev=44278&r1=44277&r2=44278&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/ADCE.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/ADCE.cpp Thu Nov 22 15:40:06 2007
@@ -34,7 +34,7 @@
 
 STATISTIC(NumBlockRemoved, "Number of basic blocks removed");
 STATISTIC(NumInstRemoved , "Number of instructions removed");
-STATISTIC(NumCallRemoved , "Number of calls and invokes removed");
+STATISTIC(NumCallRemoved , "Number of calls removed");
 
 namespace {
 //===----------------------------------------------------------------------===//
@@ -184,32 +184,6 @@
 
   AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
 
-
-  // Iterate over all invokes in the function, turning invokes into calls if
-  // they cannot throw.
-  for (Function::iterator BB = Func->begin(), E = Func->end(); BB != E; ++BB)
-    if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
-      if (Function *F = II->getCalledFunction())
-        if (AA.onlyReadsMemory(F)) {
-          // The function cannot unwind.  Convert it to a call with a branch
-          // after it to the normal destination.
-          SmallVector<Value*, 8> Args(II->op_begin()+3, II->op_end());
-          CallInst *NewCall = new CallInst(F, Args.begin(), Args.end(), "", II);
-          NewCall->takeName(II);
-          NewCall->setCallingConv(II->getCallingConv());
-          II->replaceAllUsesWith(NewCall);
-          new BranchInst(II->getNormalDest(), II);
-
-          // Update PHI nodes in the unwind destination
-          II->getUnwindDest()->removePredecessor(BB);
-          BB->getInstList().erase(II);
-
-          if (NewCall->use_empty()) {
-            BB->getInstList().erase(NewCall);
-            ++NumCallRemoved;
-          }
-        }
-
   // Iterate over all of the instructions in the function, eliminating trivially
   // dead instructions, and marking instructions live that are known to be
   // needed.  Perform the walk in depth first order so that we avoid marking any

Modified: llvm/trunk/test/Transforms/ADCE/dce_pure_invoke.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/ADCE/dce_pure_invoke.ll?rev=44278&r1=44277&r2=44278&view=diff

==============================================================================
--- llvm/trunk/test/Transforms/ADCE/dce_pure_invoke.ll (original)
+++ llvm/trunk/test/Transforms/ADCE/dce_pure_invoke.ll Thu Nov 22 15:40:06 2007
@@ -1,13 +1,15 @@
-; RUN: llvm-upgrade < %s | llvm-as | opt -adce | llvm-dis | not grep null
+; RUN: llvm-as < %s | opt -adce | llvm-dis | grep null
 
-declare int %strlen(sbyte*)
+declare i32 @strlen(i8*) readnone
 
-int %test() {
-	;; Dead call should be deleted!
-	invoke int %strlen(sbyte *null) to label %Cont unwind label %Other
-Cont:
-	ret int 0
-Other:
-	ret int 1
-}
+define i32 @test() {
+	; invoke of pure function should not be deleted!
+	invoke i32 @strlen( i8* null ) readnone
+			to label %Cont unwind label %Other		; <i32>:1 [#uses=0]
+
+Cont:		; preds = %0
+	ret i32 0
 
+Other:		; preds = %0
+	ret i32 1
+}