new testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21787 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/Reassociate/mul-neg-add.ll b/test/Transforms/Reassociate/mul-neg-add.ll
new file mode 100644 (file)
index 0000000..79eeb19
--- /dev/null
+++ b/test/Transforms/Reassociate/mul-neg-add.ll
@@ -0,0 +1,8 @@
+; RUN: llvm-as < %s | opt -reassociate -instcombine | llvm-dis | not grep 'sub int 0'
+
+int %test(int %X, int %Y, int %Z) {
+       %A = sub int 0, %X
+       %B = mul int %A, %Y
+       %C = add int %B, %Z   ; (-X)*Y + Z -> Z-X*Y
+       ret int %C
+}