[llvm-commits] [llvm] r83778 - in /llvm/trunk: lib/Transforms/Scalar/JumpThreading.cpp test/Transforms/JumpThreading/basic.ll test/Transforms/JumpThreading/dup-cond.ll

[Chris Lattner]

Author: lattner
Date: Sun Oct 11 13:39:58 2009
New Revision: 83778

URL: http://llvm.org/viewvc/llvm-project?rev=83778&view=rev
Log:
when folding duplicate conditions, delete the 
now-probably-dead instruction tree feeding it.

Removed:
    llvm/trunk/test/Transforms/JumpThreading/dup-cond.ll
Modified:
    llvm/trunk/lib/Transforms/Scalar/JumpThreading.cpp
    llvm/trunk/test/Transforms/JumpThreading/basic.ll

Modified: llvm/trunk/lib/Transforms/Scalar/JumpThreading.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/JumpThreading.cpp?rev=83778&r1=83777&r2=83778&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/JumpThreading.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/JumpThreading.cpp Sun Oct 11 13:39:58 2009
@@ -450,9 +450,11 @@
           << "' folding condition to '" << BranchDir << "': "
           << *BB->getTerminator() << '\n');
     ++NumFolds;
+    Value *OldCond = DestBI->getCondition();
     DestBI->setCondition(ConstantInt::get(Type::getInt1Ty(BB->getContext()),
                                           BranchDir));
     ConstantFoldTerminator(BB);
+    RecursivelyDeleteTriviallyDeadInstructions(OldCond);
     return true;
   }
  

Modified: llvm/trunk/test/Transforms/JumpThreading/basic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/JumpThreading/basic.ll?rev=83778&r1=83777&r2=83778&view=diff

==============================================================================
--- llvm/trunk/test/Transforms/JumpThreading/basic.ll (original)
+++ llvm/trunk/test/Transforms/JumpThreading/basic.ll Sun Oct 11 13:39:58 2009
@@ -139,3 +139,36 @@
 	ret i32 %B
 }
 
+
+;; Lexically duplicated conditionals should be threaded.
+
+
+define i32 @test6(i32 %A) {
+; CHECK: @test6
+	%tmp455 = icmp eq i32 %A, 42
+	br i1 %tmp455, label %BB1, label %BB2
+        
+BB2:
+; CHECK: call i32 @f1()
+; CHECK-NEXT: call void @f3()
+; CHECK-NEXT: ret i32 4
+	call i32 @f1()
+	br label %BB1
+        
+
+BB1:
+	%tmp459 = icmp eq i32 %A, 42
+	br i1 %tmp459, label %BB3, label %BB4
+
+BB3:
+	call i32 @f2()
+        ret i32 3
+
+BB4:
+	call void @f3()
+	ret i32 4
+}
+
+
+
+

Removed: llvm/trunk/test/Transforms/JumpThreading/dup-cond.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/JumpThreading/dup-cond.ll?rev=83777&view=auto

==============================================================================
--- llvm/trunk/test/Transforms/JumpThreading/dup-cond.ll (original)
+++ llvm/trunk/test/Transforms/JumpThreading/dup-cond.ll (removed)
@@ -1,30 +0,0 @@
-; RUN: opt < %s -jump-threading -die -S | grep icmp | count 1
-
-declare void @f1()
-declare void @f2()
-declare void @f3()
-
-define i32 @test(i32 %A) {
-	%tmp455 = icmp eq i32 %A, 42
-	br i1 %tmp455, label %BB1, label %BB2
-        
-BB2:
-	call void @f1()
-	br label %BB1
-        
-
-BB1:
-	%tmp459 = icmp eq i32 %A, 42
-	br i1 %tmp459, label %BB3, label %BB4
-
-BB3:
-	call void @f2()
-        ret i32 3
-
-BB4:
-	call void @f3()
-	ret i32 4
-}
-
-
-