Don't allow pointer types in affine expressions

We currently do not support pointer types in affine expressions. Hence, we
disallow in the SCoP detection. Later we may decide to add support for them.

This fixes PR12277

Reported-By: Sebastian Pop  <sebpop@gmail.com>
llvm-svn: 152928

2 files changed, 30 insertions, 0 deletions

diff --git a/polly/lib/Support/SCEVValidator.cpp b/polly/lib/Support/SCEVValidator.cpp
index eb26424..a70cf1a 100644
--- a/polly/lib/Support/SCEVValidator.cpp
+++ b/polly/lib/Support/SCEVValidator.cpp
@@ -279,6 +279,16 @@ public:
   ValidatorResult visitUnknown(const SCEVUnknown *Expr) {
     Value *V = Expr->getValue();
 
+    // We currently only support integer types. It may be useful to support
+    // pointer types, e.g. to support code like:
+    //
+    //   if (A)
+    //     A[i] = 1;
+    //
+    // See test/CodeGen/20120316-InvalidCast.ll
+    if (!Expr->getType()->isIntegerTy())
+      return ValidatorResult(SCEVType::INVALID);
+
     if (isa<UndefValue>(V))
       return ValidatorResult(SCEVType::INVALID);
 
diff --git a/polly/test/CodeGen/20120316-InvalidCast.ll b/polly/test/CodeGen/20120316-InvalidCast.ll
new file mode 100644
index 0000000..9628877
--- /dev/null
+++ b/polly/test/CodeGen/20120316-InvalidCast.ll
@@ -0,0 +1,20 @@
+; RUN: opt %loadPolly %defaultOpts -polly-codegen %s
+
+target datalayout = "e-p:32:32:32-i64:64:64-i32:32:32-i16:16:16-i1:32:32f64:64:64-f32:32:32-a0:0-n32"
+target triple = "hexagon-unknown-linux-gnu"
+
+define void @fixup_gotos(i32* %A, i32* %data) nounwind {
+entry:
+  br label %if
+
+if:
+  %cond = icmp eq i32* %A, null
+  br i1 %cond, label %last, label %then
+
+then:
+  store i32 1, i32* %data, align 4
+  br label %last
+
+last:
+  ret void
+}