| Message ID | bb65410a-0b4d-d7d8-f909-97c87c8de4f5@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [Arm] : MVE Don't use lsll for 32-bit shifts scalar | expand |
> -----Original Message----- > From: Andre Vieira (lists) <andre.simoesdiasvieira@arm.com> > Sent: 07 April 2020 11:43 > To: gcc-patches@gcc.gnu.org > Cc: Kyrylo Tkachov <Kyrylo.Tkachov@arm.com> > Subject: [PATCH][GCC][Arm]: MVE Don't use lsll for 32-bit shifts scalar > > Hi, > > After fixing the v[id]wdups using the "moving the wrap parameter" into > the top-end of a DImode operand using a shift, I noticed we were using > lsll for 32-bit shifts in scalars, where we don't need to, as we can > simply do a move, which is much better if we don't need to use the > bottom part. > > We can solve this in a better way, but for now this will do. > > Regression tested on arm-none-eabi. > > Is this OK for trunk? Ok. Thanks, Kyrill > > 2020-04-07 Andre Vieira <andre.simoesdiasvieira@arm.com> > > * config/arm/arm.d (ashldi3): Don't use lsll for constant 32-bit > shifts.
diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md index 1a7ea0d701e5677965574d877d0fe4b2f5bc149f..6d5560398dae3d0ace0342b4907542d2a6865f70 100644 --- a/gcc/config/arm/arm.md +++ b/gcc/config/arm/arm.md @@ -4422,7 +4422,8 @@ (define_expand "ashldi3" operands[2] = force_reg (SImode, operands[2]); /* Armv8.1-M Mainline double shifts are not expanded. */ - if (arm_reg_or_long_shift_imm (operands[2], GET_MODE (operands[2]))) + if (arm_reg_or_long_shift_imm (operands[2], GET_MODE (operands[2])) + && (REG_P (operands[2]) || INTVAL(operands[2]) != 32)) { if (!reg_overlap_mentioned_p(operands[0], operands[1])) emit_insn (gen_movdi (operands[0], operands[1]));