splitLoop does not handle split condition EQ.

Fixes PR 2805

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56321 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/LoopIndexSplit.cpp b/lib/Transforms/Scalar/LoopIndexSplit.cpp
index 8cafe7424d0126f3477290703a251dc0d4cbc5f1..085223cd814e2196ef9e7a8d367395fab6f146c3 100644 (file)
--- a/lib/Transforms/Scalar/LoopIndexSplit.cpp
+++ b/lib/Transforms/Scalar/LoopIndexSplit.cpp
@@ -1430,6 +1430,12 @@ bool LoopIndexSplit::splitLoop(SplitInfo &SD) {
   if (!safeSplitCondition(SD))
     return false;
 
+  // If split condition EQ is not handled.
+  if (ICmpInst *ICMP = dyn_cast<ICmpInst>(SD.SplitCondition)) {
+    if (ICMP->getPredicate() == ICmpInst::ICMP_EQ)
+      return false;
+  }
+  
   BasicBlock *SplitCondBlock = SD.SplitCondition->getParent();
   
   // Unable to handle triangle loops at the moment.

diff --git a/test/Transforms/LoopIndexSplit/2008-09-20-Crash.ll b/test/Transforms/LoopIndexSplit/2008-09-20-Crash.ll
new file mode 100644 (file)
index 0000000..f66edcd
--- /dev/null
+++ b/test/Transforms/LoopIndexSplit/2008-09-20-Crash.ll
@@ -0,0 +1,38 @@
+; RUN: llvm-as < %s | opt -loop-index-split -disable-output
+; PR 2805
+@g_330 = common global i32 0           ; <i32*> [#uses=1]
+
+define i32 @func_45(i32 %p_47) nounwind {
+entry:
+       br label %bb
+
+bb:            ; preds = %bb3, %entry
+       %p_47_addr.0.reg2mem.0 = phi i32 [ 0, %entry ], [ %2, %bb3 ]            ; <i32> [#uses=2]
+       %0 = icmp eq i32 %p_47_addr.0.reg2mem.0, 0              ; <i1> [#uses=1]
+       br i1 %0, label %bb2, label %bb1
+
+bb1:           ; preds = %bb
+       %1 = tail call i32 (...)* @func_70( i32 1 ) nounwind            ; <i32> [#uses=0]
+       br label %bb3
+
+bb2:           ; preds = %bb
+       store i32 1, i32* @g_330, align 4
+       br label %bb3
+
+bb3:           ; preds = %bb2, %bb1
+       %2 = add i32 %p_47_addr.0.reg2mem.0, 1          ; <i32> [#uses=3]
+       %3 = icmp ult i32 %2, 22                ; <i1> [#uses=1]
+       br i1 %3, label %bb, label %bb6
+
+bb6:           ; preds = %bb3
+       %.lcssa = phi i32 [ %2, %bb3 ]          ; <i32> [#uses=1]
+       %4 = tail call i32 (...)* @func_95( i32 %.lcssa ) nounwind              ; <i32> [#uses=1]
+       %5 = tail call i32 (...)* @func_56( i32 %4 ) nounwind           ; <i32> [#uses=0]
+       ret i32 undef
+}
+
+declare i32 @func_70(...)
+
+declare i32 @func_95(...)
+
+declare i32 @func_56(...)