Displaying 3 results from an estimated 3 matches for "frdrr".
Did you mean:
rdrr
2010 Sep 04
6
[LLVMdev] Possible missed optimization?
Hello, while testing trivial functions in my backend i noticed a suboptimal
way of assigning regs that had the following pattern, consider the following
function:
typedef unsigned short t;
t foo(t a, t b)
{
t a4 = b^a^18;
return a4;
}
Argument "a" is passed in R15:R14 and argument "b" is passed in R13:R12, the
return value is stored in R15:R14.
Producing the
2010 Sep 04
1
[LLVMdev] Possible missed optimization?
Indeed, i've marked it as commutable:
let isCommutable = 1,
isTwoAddress = 1 in
def XORRdRr : FRdRr<0b0010,
0b01,
(outs GPR8:$dst),
(ins GPR8:$src1, GPR8:$src2),
"xor\t$dst, $src2",
[(set GPR8:$dst, (xor GPR8:$src1, GPR8:$src2))]>;
-------------- next part --------------
An HTML att...
2010 Sep 04
0
[LLVMdev] Possible missed optimization?
Hello
> and as the return value. Is this a missed optimization from LLVM or did i
> miss something out?
> Changing the register allocation order didnt work.
What are the patterns for xor / mov ?
--
With best regards, Anton Korobeynikov
Faculty of Mathematics and Mechanics, Saint Petersburg State University