[llvm-commits] [llvm] r121693 - in /llvm/trunk: lib/Transforms/Utils/SimplifyCFG.cpp test/Transforms/SimplifyCFG/switch_create.ll

[Chris Lattner]

Author: lattner
Date: Mon Dec 13 01:41:29 2010
New Revision: 121693

URL: http://llvm.org/viewvc/llvm-project?rev=121693&view=rev
Log:
Completely disable the optimization I added in r121680 until
I can track down a miscompile.  This should bring the buildbots
back to life

Modified:
    llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
    llvm/trunk/test/Transforms/SimplifyCFG/switch_create.ll

Modified: llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp?rev=121693&r1=121692&r2=121693&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp Mon Dec 13 01:41:29 2010
@@ -331,8 +331,8 @@
                                             isEQ)) {
       if (LHS == RHS)
         return LHS;
+      Vals.resize(NumVals);
     }
-    Vals.resize(NumVals);
 
     // The RHS of the or/and can't be folded in and we haven't used "Extra" yet,
     // set it and return success.
@@ -348,12 +348,13 @@
   // If the LHS can't be folded in, but Extra is available and RHS can, try to
   // use LHS as Extra.
   if (Extra == 0 || Extra == I->getOperand(0)) {
+    Value *OldExtra = Extra;
     Extra = I->getOperand(0);
     if (Value *RHS = GatherConstantCompares(I->getOperand(1), Vals, Extra, TD,
                                             isEQ))
       return RHS;
-    Vals.resize(NumValsBeforeLHS);
-    Extra = 0;
+    assert(Vals.size() == NumValsBeforeLHS);
+    Extra = OldExtra;
   }
   
   return 0;
@@ -1908,6 +1909,8 @@
   // then we evaluate them with an explicit branch first.  Split the block
   // right before the condbr to handle it.
   if (ExtraCase) {
+    return false;
+    
     BasicBlock *NewBB = BB->splitBasicBlock(BI, "switch.early.test");
     // Remove the uncond branch added to the old block.
     TerminatorInst *OldTI = BB->getTerminator();

Modified: llvm/trunk/test/Transforms/SimplifyCFG/switch_create.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SimplifyCFG/switch_create.ll?rev=121693&r1=121692&r2=121693&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/SimplifyCFG/switch_create.ll (original)
+++ llvm/trunk/test/Transforms/SimplifyCFG/switch_create.ll Mon Dec 13 01:41:29 2010
@@ -168,13 +168,13 @@
   ret void
   
 ; CHECK: @test7
-; CHECK:   %cmp = icmp ult i32 %x, 32
-; CHECK:   br i1 %cmp, label %if.then, label %switch.early.test
-; CHECK: switch.early.test:
-; CHECK:   switch i8 %c, label %if.end [
-; CHECK:     i8 99, label %if.then
-; CHECK:     i8 97, label %if.then
-; CHECK:   ]
+; HECK:   %cmp = icmp ult i32 %x, 32
+; HECK:   br i1 %cmp, label %if.then, label %switch.early.test
+; HECK: switch.early.test:
+; HECK:   switch i8 %c, label %if.end [
+; HECK:     i8 99, label %if.then
+; HECK:     i8 97, label %if.then
+; HECK:   ]
 }
 
 define i32 @test8(i8 zeroext %c, i32 %x, i1 %C) nounwind ssp noredzone {
@@ -197,14 +197,15 @@
   ret i32 0
   
 ; CHECK: @test8
-; CHECK: switch.early.test:
-; CHECK:   switch i8 %c, label %if.end [
-; CHECK:     i8 99, label %if.then
-; CHECK:     i8 97, label %if.then
-; CHECK:   ]
-; CHECK:   %A = phi i32 [ 0, %entry ], [ 42, %switch.early.test ], [ 42, %N ], [ 42, %switch.early.test ]
+; HECK: switch.early.test:
+; HECK:   switch i8 %c, label %if.end [
+; HECK:     i8 99, label %if.then
+; HECK:     i8 97, label %if.then
+; HECK:   ]
+; HECK:   %A = phi i32 [ 0, %entry ], [ 42, %switch.early.test ], [ 42, %N ], [ 42, %switch.early.test ]
 }
 
+;; This is "Example 7" from http://blog.regehr.org/archives/320
 define i32 @test9(i8 zeroext %c) nounwind ssp noredzone {
 entry:
   %cmp = icmp ult i8 %c, 33
@@ -253,20 +254,20 @@
   
 ; CHECK: @test9
 ; CHECK:   %cmp = icmp ult i8 %c, 33
-; CHECK:   br i1 %cmp, label %lor.end, label %switch.early.test
+; HECK:   br i1 %cmp, label %lor.end, label %switch.early.test
 
-; CHECK: switch.early.test:
-; CHECK:   switch i8 %c, label %lor.rhs [
-; CHECK:     i8 46, label %lor.end
-; CHECK:     i8 44, label %lor.end
-; CHECK:     i8 58, label %lor.end
-; CHECK:     i8 59, label %lor.end
-; CHECK:     i8 60, label %lor.end
-; CHECK:     i8 62, label %lor.end
-; CHECK:     i8 34, label %lor.end
-; CHECK:     i8 92, label %lor.end
-; CHECK:     i8 39, label %lor.end
-; CHECK:   ]
+; HECK: switch.early.test:
+; HECK:   switch i8 %c, label %lor.rhs [
+; HECK:     i8 46, label %lor.end
+; HECK:     i8 44, label %lor.end
+; HECK:     i8 58, label %lor.end
+; HECK:     i8 59, label %lor.end
+; HECK:     i8 60, label %lor.end
+; HECK:     i8 62, label %lor.end
+; HECK:     i8 34, label %lor.end
+; HECK:     i8 92, label %lor.end
+; HECK:     i8 39, label %lor.end
+; HECK:   ]
 }