Fix a bug where we'd try to find a scev value for a bitcast operand,

even though the bitcast operand did not have integer type.  This fixes
PR1814.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44286 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index cc6cde2ba212bc2985fe940d8762e4ae53f13443..1508fd0c524a9437bcc2901e43937a56114dde1f 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -1470,6 +1470,9 @@ static uint32_t GetMinTrailingZeros(SCEVHandle S) {
 /// Analyze the expression.
 ///
 SCEVHandle ScalarEvolutionsImpl::createSCEV(Value *V) {
+  if (!isa<IntegerType>(V->getType()))
+    return SE.getUnknown(V);
+    
   if (Instruction *I = dyn_cast<Instruction>(V)) {
     switch (I->getOpcode()) {
     case Instruction::Add:
@@ -2076,6 +2079,11 @@ SCEVHandle ScalarEvolutionsImpl::getSCEVAtScope(SCEV *V, const Loop *L) {
           if (Constant *C = dyn_cast<Constant>(Op)) {
             Operands.push_back(C);
           } else {
+            // If any of the operands is non-constant and if they are
+            // non-integer, don't even try to analyze them with scev techniques.
+            if (!isa<IntegerType>(Op->getType()))
+              return V;
+              
             SCEVHandle OpV = getSCEVAtScope(getSCEV(Op), L);
             if (SCEVConstant *SC = dyn_cast<SCEVConstant>(OpV))
               Operands.push_back(ConstantExpr::getIntegerCast(SC->getValue(), 

diff --git a/test/Transforms/IndVarsSimplify/2007-11-23-BitcastCrash.ll b/test/Transforms/IndVarsSimplify/2007-11-23-BitcastCrash.ll
new file mode 100644 (file)
index 0000000..555cadd
--- /dev/null
+++ b/test/Transforms/IndVarsSimplify/2007-11-23-BitcastCrash.ll
@@ -0,0 +1,20 @@
+; RUN: llvm-as < %s | opt -indvars -disable-output
+; PR1814
+target datalayout = "e-p:32:32-f64:32:64-i64:32:64-f80:32:32"
+
+define void @FuncAt1938470480(i32, i32, i32, i32, i32, i32, i32, i32, i64, i64, i64, i64, i64, i64, i64, i64, i1, i1, i1, i1, i1, i1) {
+EntryBlock:
+       br label %asmBlockAt738ab7f3
+
+asmBlockAt738ab9b0:            ; preds = %asmBlockAt738ab7f3
+       %.lcssa6 = phi i64 [ %23, %asmBlockAt738ab7f3 ]         ; <i64> [#uses=0]
+       ret void
+
+asmBlockAt738ab7f3:            ; preds = %asmBlockAt738ab7f3, %EntryBlock
+       %ebp95 = phi i32 [ 128, %EntryBlock ], [ %24, %asmBlockAt738ab7f3 ]             ; <i32> [#uses=2]
+       sub <4 x i16> zeroinitializer, zeroinitializer          ; <<4 x i16>>:22 [#uses=1]
+       bitcast <4 x i16> %22 to i64            ; <i64>:23 [#uses=1]
+       add i32 %ebp95, -64             ; <i32>:24 [#uses=1]
+       icmp ult i32 %ebp95, 64         ; <i1>:25 [#uses=1]
+       br i1 %25, label %asmBlockAt738ab9b0, label %asmBlockAt738ab7f3
+}