Hi,
This is a backport from trunk/gcc-9 that I think we need now that we
have backported the casp LSE instructions.
Bootstrapped and regression tested on aarch64.
Is this OK for gcc-8?
Cheers,
Andre
The LSE CASP instruction requires values to be placed in even
register pairs. A solution involving two additional register
classes was rejected in favor of the much simpler solution of
simply requiring all TImode values to be aligned.
gcc/ChangeLog:
2020-04-29 Andre Vieira <andre.simoesdiasvie...@arm.com>
Backport from mainline.
2018-10-31 Richard Henderson <richard.hender...@linaro.org>
* config/aarch64/aarch64.c (aarch64_hard_regno_mode_ok): Force
16-byte modes held in GP registers to use an even regno.
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index
5eec1aae54abe04b8320deaf8202621c8e193c01..525deba56ea363a621cccec1a923da241908dd06
100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -1369,10 +1369,14 @@ aarch64_hard_regno_mode_ok (unsigned regno,
machine_mode mode)
if (regno == FRAME_POINTER_REGNUM || regno == ARG_POINTER_REGNUM)
return mode == Pmode;
- if (GP_REGNUM_P (regno) && known_le (GET_MODE_SIZE (mode), 16))
- return true;
-
- if (FP_REGNUM_P (regno))
+ if (GP_REGNUM_P (regno))
+ {
+ if (known_le (GET_MODE_SIZE (mode), 8))
+ return true;
+ else if (known_le (GET_MODE_SIZE (mode), 16))
+ return (regno & 1) == 0;
+ }
+ else if (FP_REGNUM_P (regno))
{
if (vec_flags & VEC_STRUCT)
return end_hard_regno (mode, regno) - 1 <= V31_REGNUM;
