[PATCH][GCC] Algorithmic optimization in match and simplify
Marc Glisse
marc.glisse@inria.fr
Fri Aug 28 18:13:00 GMT 2015
(not a review, I haven't even read the whole patch)
On Fri, 28 Aug 2015, Andre Vieira wrote:
> 2015-08-03 Andre Vieira <andre.simoesdiasvieira@arm.com>
>
> * match.pd: Added new patterns:
> ((X {&,<<,>>} C0) {|,^} C1) {^,|} C2)
> (X {|,^,&} C0) {<<,>>} C1 -> (X {<<,>>} C1) {|,^,&} (C0 {<<,>>} C1)
+(for op0 (rshift rshift lshift lshift bit_and bit_and)
+ op1 (bit_ior bit_xor bit_ior bit_xor bit_ior bit_xor)
+ op2 (bit_xor bit_ior bit_xor bit_ior bit_xor bit_ior)
You can nest for-loops, it seems clearer as:
(for op0 (rshift lshift bit_and)
(for op1 (bit_ior bit_xor)
op2 (bit_xor bit_ior)
+(simplify
+ (op2:c
+ (op1:c
+ (op0 @0 INTEGER_CST@1) INTEGER_CST@2) INTEGER_CST@3)
I suspect you will want more :s (single_use) and less :c (canonicalization
should put constants in second position).
+ C1 = wi::bit_and_not (C1,C2);
Space after ','.
Having wide_int_storage in many places is surprising, I can't find similar
code anywhere else in gcc.
--
Marc Glisse
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