It's easy to handle SLE/SGE when the loop has a unit stride.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60748 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 24 insertions, 0 deletions

diff --git a/test/Analysis/ScalarEvolution/2008-12-08-FiniteSGE.ll b/test/Analysis/ScalarEvolution/2008-12-08-FiniteSGE.ll
new file mode 100644
index 0000000..a9a7c05
--- /dev/null
+++ b/test/Analysis/ScalarEvolution/2008-12-08-FiniteSGE.ll
@@ -0,0 +1,24 @@
+; RUN: llvm-as < %s | opt -analyze -scalar-evolution | grep {255 iterations}
+
+define i32 @foo(i32 %x, i32 %y, i32* %lam, i32* %alp) nounwind {
+bb1.thread:
+	br label %bb1
+
+bb1:		; preds = %bb1, %bb1.thread
+	%indvar = phi i32 [ 0, %bb1.thread ], [ %indvar.next, %bb1 ]		; <i32> [#uses=4]
+	%i.0.reg2mem.0 = sub i32 255, %indvar		; <i32> [#uses=2]
+	%0 = getelementptr i32* %alp, i32 %i.0.reg2mem.0		; <i32*> [#uses=1]
+	%1 = load i32* %0, align 4		; <i32> [#uses=1]
+	%2 = getelementptr i32* %lam, i32 %i.0.reg2mem.0		; <i32*> [#uses=1]
+	store i32 %1, i32* %2, align 4
+	%3 = sub i32 254, %indvar		; <i32> [#uses=1]
+	%4 = icmp slt i32 %3, 0		; <i1> [#uses=1]
+	%indvar.next = add i32 %indvar, 1		; <i32> [#uses=1]
+	br i1 %4, label %bb2, label %bb1
+
+bb2:		; preds = %bb1
+	%tmp10 = mul i32 %indvar, %x		; <i32> [#uses=1]
+	%z.0.reg2mem.0 = add i32 %tmp10, %y		; <i32> [#uses=1]
+	%5 = add i32 %z.0.reg2mem.0, %x		; <i32> [#uses=1]
+	ret i32 %5
+}