[llvm-commits] [llvm] r75642 - in /llvm/trunk: lib/Transforms/Scalar/SimplifyCFGPass.cpp test/Transforms/SimplifyCFG/2009-07-13-no-delete-asm.ll
Dale Johannesen
dalej at apple.com
Tue Jul 14 10:48:25 PDT 2009
Author: johannes
Date: Tue Jul 14 12:48:25 2009
New Revision: 75642
URL: http://llvm.org/viewvc/llvm-project?rev=75642&view=rev
Log:
Revert 75571; I'm convinced this isn't the right thing to do.
Removed:
llvm/trunk/test/Transforms/SimplifyCFG/2009-07-13-no-delete-asm.ll
Modified:
llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp?rev=75642&r1=75641&r2=75642&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/SimplifyCFGPass.cpp Tue Jul 14 12:48:25 2009
@@ -109,8 +109,6 @@
if (!Reachable.insert(BB))
continue;
- bool AsmFound = false;
- StoreInst *UndefStore = 0;
// Do a quick scan of the basic block, turning any obviously unreachable
// instructions into LLVM unreachable insts. The instruction combining pass
// canonicalizes unreachable insts into stores to null or undef.
@@ -127,27 +125,20 @@
}
break;
}
- if (isa<InlineAsm>(CI->getOperand(0)))
- AsmFound = true;
}
if (StoreInst *SI = dyn_cast<StoreInst>(BBI)) {
Value *Ptr = SI->getOperand(1);
-
- if ((isa<UndefValue>(Ptr) ||
- (isa<ConstantPointerNull>(Ptr) &&
- cast<PointerType>(Ptr->getType())->getAddressSpace() == 0)) &&
- !UndefStore)
- UndefStore = SI;
+
+ if (isa<UndefValue>(Ptr) ||
+ (isa<ConstantPointerNull>(Ptr) &&
+ cast<PointerType>(Ptr->getType())->getAddressSpace() == 0)) {
+ ChangeToUnreachable(SI, Context);
+ Changed = true;
+ break;
+ }
}
}
- // We can't delete asm's just because their inputs are undefined;
- // xor R, R is a common idiom for zeroing a register, for example.
- // Assume user knows what he is doing.
- if (UndefStore && !AsmFound) {
- ChangeToUnreachable(UndefStore, Context);
- Changed = true;
- }
// Turn invokes that call 'nounwind' functions into ordinary calls.
if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
Removed: llvm/trunk/test/Transforms/SimplifyCFG/2009-07-13-no-delete-asm.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SimplifyCFG/2009-07-13-no-delete-asm.ll?rev=75641&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/SimplifyCFG/2009-07-13-no-delete-asm.ll (original)
+++ llvm/trunk/test/Transforms/SimplifyCFG/2009-07-13-no-delete-asm.ll (removed)
@@ -1,11 +0,0 @@
-; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis | grep xor
-; ModuleID = '<stdin>'
-target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
-target triple = "i386-apple-darwin9.6"
-
-define void @bar() nounwind {
-entry:
- store i16 undef, i16* null
- %asmtmp = call i32 asm sideeffect "xor $0, $0", "=={bx},rm,~{dirflag},~{fpsr},~{flags},~{memory}"(i16 undef) nounwind ; <i32> [#uses=0]
- ret void
-}
More information about the llvm-commits
mailing list