mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-29 10:32:47 +00:00
7c65d4345e
Make use of the END. facility on all files > 1K so that we aren't wasting CPU cycles searching for RUN: lines that we'll never find. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36059 91177308-0d34-0410-b5e6-96231b3b80d8
57 lines
1.3 KiB
LLVM
57 lines
1.3 KiB
LLVM
; 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
|
|
}
|
|
|