summaryrefslogtreecommitdiffstats
path: root/test/CodeGen/X86/2005-01-17-CycleInDAG.ll
diff options
context:
space:
mode:
Diffstat (limited to 'test/CodeGen/X86/2005-01-17-CycleInDAG.ll')
-rw-r--r--test/CodeGen/X86/2005-01-17-CycleInDAG.ll17
1 files changed, 17 insertions, 0 deletions
diff --git a/test/CodeGen/X86/2005-01-17-CycleInDAG.ll b/test/CodeGen/X86/2005-01-17-CycleInDAG.ll
new file mode 100644
index 0000000..32fafc6
--- /dev/null
+++ b/test/CodeGen/X86/2005-01-17-CycleInDAG.ll
@@ -0,0 +1,17 @@
+; This testcase was distilled from 132.ijpeg. Bsaically we cannot fold the
+; load into the sub instruction here as it induces a cycle in the dag, which
+; is invalid code (there is no correct way to order the instruction). Check
+; that we do not fold the load into the sub.
+
+; RUN: llc < %s -march=x86 | not grep sub.*GLOBAL
+
+@GLOBAL = external global i32 ; <i32*> [#uses=1]
+
+define i32 @test(i32* %P1, i32* %P2, i32* %P3) {
+ %L = load i32* @GLOBAL ; <i32> [#uses=1]
+ store i32 12, i32* %P2
+ %Y = load i32* %P3 ; <i32> [#uses=1]
+ %Z = sub i32 %Y, %L ; <i32> [#uses=1]
+ ret i32 %Z
+}
+