; If we have an 'and' of the result of an 'or', and one of the 'or' operands ; cannot have contributed any of the resultant bits, delete the or. This ; occurs for very common C/C++ code like this: ; ; struct foo { int A : 16; int B : 16; }; ; void test(struct foo *F, int X, int Y) { ; F->A = X; F->B = Y; ; } ; ; Which corresponds to test1. ; RUN: llvm-upgrade < %s | llvm-as | opt -instcombine | llvm-dis | \ ; RUN: not grep {or } ; END. int %test1(int %X, int %Y) { %A = and int %X, 7 %B = and int %Y, 8 %C = or int %A, %B %D = and int %C, 7 ;; This cannot include any bits from %Y! ret int %D } int %test2(int %X, ubyte %Y) { %B = cast ubyte %Y to int %C = or int %X, %B %D = and int %C, 65536 ;; This cannot include any bits from %Y! ret int %D } int %test3(int %X, int %Y) { %B = shl int %Y, ubyte 1 %C = or int %X, %B %D = and int %C, 1 ;; This cannot include any bits from %Y! ret int %D } uint %test4(uint %X, uint %Y) { %B = shr uint %Y, ubyte 31 %C = or uint %X, %B %D = and uint %C, 2 ;; This cannot include any bits from %Y! ret uint %D } int %or_test1(int %X, int %Y) { %A = and int %X, 1 %B = or int %A, 1 ;; This cannot include any bits from X! ret int %B } ubyte %or_test2(ubyte %X, ubyte %Y) { %A = shl ubyte %X, ubyte 7 %B = or ubyte %A, 128 ;; This cannot include any bits from X! ret ubyte %B }