On Fri, Nov 17, 2017 at 09:45:35AM +0000, Thomas Preudhomme wrote: > > Bootstrapped/regtested on {x86_64,i686,powerpc64le,powerpc64}-linux, ok for > > trunk? > > > > The cases this patch can handle are less common than rhs_code INTEGER_CST > > (stores of constants to adjacent memory) or MEM_REF (adjacent memory > > copying), but are more common than the bitwise ops, during combined > > x86_64+i686 bootstraps/regtests it triggered: > > lrotate_expr 974 2528 > > nop_expr 720 1711 > > (lrotate_expr stands for bswap, nop_expr for identity, the first column is > > the actual count of such new stores, the second is the original number of > > stores that have been optimized this way). > > Are you saying that lrotate_expr is just the title and it also includes 32- > and 64-bit bswap or is it only the count of lrotate_expr nodes?
The rhs_code field is magic shorthand, it could be perhaps also some enum, the thing is that I need values for: 1) a constant satisfying rhs_valid_for_store_merging_p predicate (usually INTEGER_CST, but it can be something different). Right now I'm using INTEGER_CST for all those 2) a memory load; right now I'm using MEM_REF for all kinds of memory loads 3) BIT_{AND,IOR,XOR}_EXPR - these are the main reason for not using some specialized enums, but actually a tree_code; the advantage is that then there is no need to translate it in any way 4) bswap (any kind); the patch uses LROTATE_EXPR for that, again, like in 1) and 2) just a placeholder 5) bswap framework determined nop; the patch uses NOP_EXPR for that; a placeholder Another possibility would be specialized enum, perhaps one where SMOP_{CONSTANT,MEMORY,BSWAP,NOP} would be MAX_TREE_CODES + {1,2,3,4} and SMOP_{AND,IOR,XOR} would be equal to BIT_{AND,IOR,XOR}_EXPR for easier translations between. > > @@ -1141,7 +1206,7 @@ pass_optimize_bswap::execute (function * > > inserted smaller bswap replacements as sub-patterns, the wider > > variant wouldn't be detected. */ > > for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi);) > > - { > > + { > > Nit: could this be done when moving the code in the previous patch instead? Sure, can do that there. Jakub