On Fri, May 01, 2015 at 09:24:20AM +0100, Kyrill Tkachov wrote: > Hi all, > > It occurs to me that in the IOR-of-shifts form of the rev16 operation we > should be costing the operand properly. For that we'd want to reuse the > aarch_rev16_p function that does all the heavy lifting and get it to write > the innermost operand of the rev16 for further costing. In the process we > relax that function a bit to accept any rtx as the operand, not just REGs so > that we can calculate the cost of moving them in a register appropriately. > > This patch does just that and updates the arm and aarch64 callsites > appropriately so that the operands are processed properly. > > In practice I don't expect this to make much difference since this patterns > occurs rarely anyway, but it seems like the 'right thing to do' (TM). > > Bootstrapped and tested on arm,aarch64. > > Ok for trunk?
Looks OK for aarch64, please wait for an Ack from an arm maintainer. Cheers, James > 2015-05-01 Kyrylo Tkachov <kyrylo.tkac...@arm.com> > > * config/arm/aarch-common-protos.h (aarch_rev16_p): Update signature > to take a second argument. > * config/arm/aarch-common.c (aarch_rev16_p): Add second argument. > Write inner-most rev16 argument to it if recognised. > (aarch_rev16_p_1): Likewise. > * config/arm/arm.c (arm_new_rtx_costs): Properly cost rev16 operand > in the IOR case. > * config/aarch64/aarch64.c (aarch64_rtx_costs): Likewise.
