Perform mul combine when multiplying wiht negative constants.
Patch by Weiming Zhao!
This fixes PR12212
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153049 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/ARM/mul_const.ll b/test/CodeGen/ARM/mul_const.ll
index 3cb8a8e..c50a233 100644
--- a/test/CodeGen/ARM/mul_const.ll
+++ b/test/CodeGen/ARM/mul_const.ll
@@ -41,3 +41,45 @@
ret i32 %0
}
+define i32 @tn9(i32 %v) nounwind readnone {
+entry:
+; CHECK: tn9:
+; CHECK: add r0, r0, r0, lsl #3
+; CHECK: rsb r0, r0, #0
+ %0 = mul i32 %v, -9
+ ret i32 %0
+}
+
+define i32 @tn7(i32 %v) nounwind readnone {
+entry:
+; CHECK: tn7:
+; CHECK: sub r0, r0, r0, lsl #3
+ %0 = mul i32 %v, -7
+ ret i32 %0
+}
+
+define i32 @tn5(i32 %v) nounwind readnone {
+entry:
+; CHECK: tn5:
+; CHECK: add r0, r0, r0, lsl #2
+; CHECK: rsb r0, r0, #0
+ %0 = mul i32 %v, -5
+ ret i32 %0
+}
+
+define i32 @tn3(i32 %v) nounwind readnone {
+entry:
+; CHECK: tn3:
+; CHECK: sub r0, r0, r0, lsl #2
+ %0 = mul i32 %v, -3
+ ret i32 %0
+}
+
+define i32 @tn12288(i32 %v) nounwind readnone {
+entry:
+; CHECK: tn12288:
+; CHECK: sub r0, r0, r0, lsl #2
+; CHECK: lsl{{.*}}#12
+ %0 = mul i32 %v, -12288
+ ret i32 %0
+}