Properly check if a CMPZ node is in fact comparing against zero
This was left implicit and never ever checked, which means we could have a CMPZ against some non-zero value and we were carrying on with BFI conversion regardless.
Caught by Oliver Stannard using csmith; regression test added.
llvm-svn: 253195
diff --git a/llvm/test/CodeGen/ARM/bfi.ll b/llvm/test/CodeGen/ARM/bfi.ll
index 39bcbf2..893fef3 100644
--- a/llvm/test/CodeGen/ARM/bfi.ll
+++ b/llvm/test/CodeGen/ARM/bfi.ll
@@ -158,3 +158,14 @@
%sel = select i1 %cmp, i32 %y2, i32 %or
ret i32 %sel
}
+
+define i32 @f13(i32 %x, i32 %y) {
+; CHECK-LABEL: f13:
+; CHECK-NOT: bfi
+ %y2 = and i32 %y, 4294967040 ; 0xFFFFFF00
+ %and = and i32 %x, 4
+ %or = or i32 %y2, 16
+ %cmp = icmp eq i32 %and, 42 ; Not comparing against zero!
+ %sel = select i1 %cmp, i32 %y2, i32 %or
+ ret i32 %sel
+}