1 ; If we have an 'and' of the result of an 'or', and one of the 'or' operands
2 ; cannot have contributed any of the resultant bits, delete the or. This
3 ; occurs for very common C/C++ code like this:
5 ; struct foo { int A : 16; int B : 16; };
6 ; void test(struct foo *F, int X, int Y) {
10 ; Which corresponds to test1.
12 ; RUN: llvm-upgrade < %s | llvm-as | opt -instcombine | llvm-dis | \
16 int %test1(int %X, int %Y) {
20 %D = and int %C, 7 ;; This cannot include any bits from %Y!
24 int %test2(int %X, ubyte %Y) {
25 %B = cast ubyte %Y to int
27 %D = and int %C, 65536 ;; This cannot include any bits from %Y!
31 int %test3(int %X, int %Y) {
32 %B = shl int %Y, ubyte 1
34 %D = and int %C, 1 ;; This cannot include any bits from %Y!
38 uint %test4(uint %X, uint %Y) {
39 %B = shr uint %Y, ubyte 31
41 %D = and uint %C, 2 ;; This cannot include any bits from %Y!
45 int %or_test1(int %X, int %Y) {
47 %B = or int %A, 1 ;; This cannot include any bits from X!
51 ubyte %or_test2(ubyte %X, ubyte %Y) {
52 %A = shl ubyte %X, ubyte 7
53 %B = or ubyte %A, 128 ;; This cannot include any bits from X!