fdo-mirrors/mesa
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/mesa/mesa.git synced 2026-05-06 13:48:06 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

aco: fix 64-bit trunc with negative exponents on GFX6

Browse source 
v_frexp_exp returns the exponent as an unsigned value.

Also, v_ashr returns either 0 or -1 depending on the sign of the
source operand, but what we want is only the sign bit.

Fixes a bunch of recent dEQP-VK.glsl.builtin.precision_double.* tests.

Cc: <mesa-stable@lists.freedesktop.org>
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4921>
(cherry picked from commit 3fba0a7a6f)
This commit is contained in:
Samuel Pitoiset 2020-05-06 15:34:07 +02:00 • committed by Eric Engestrom
parent c4b59dbe81
commit fa01a9397f
2 changed files with 4 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
.pick_status.json
View file

@ -868,7 +868,7 @@
"description": "aco: fix 64-bit trunc with negative exponents on GFX6",
"nominated": true,
"nomination_type": 0,
"resolution": 0,
"resolution": 1,
"master_sha": null,
"because_sha": null
},

5
src/amd/compiler/aco_instruction_selection.cpp
View file

@ -884,7 +884,8 @@ Temp emit_trunc_f64(isel_context *ctx, Builder& bld, Definition dst, Temp val)
bld.pseudo(aco_opcode::p_split_vector, Definition(val_lo), Definition(val_hi), val);
/* Extract the exponent and compute the unbiased value. */
Temp exponent = bld.vop1(aco_opcode::v_frexp_exp_i32_f64, bld.def(v1), val);
Temp exponent = bld.vop3(aco_opcode::v_bfe_u32, bld.def(v1), val_hi, Operand(20u), Operand(11u));
exponent = bld.vsub32(bld.def(v1), exponent, Operand(1023u));
/* Extract the fractional part. */
Temp fract_mask = bld.pseudo(aco_opcode::p_create_vector, bld.def(v2), Operand(-1u), Operand(0x000fffffu));
@ -900,7 +901,7 @@ Temp emit_trunc_f64(isel_context *ctx, Builder& bld, Definition dst, Temp val)
fract_hi = bld.vop2(aco_opcode::v_and_b32, bld.def(v1), val_hi, tmp);
/* Get the sign bit. */
Temp sign = bld.vop2(aco_opcode::v_ashr_i32, bld.def(v1), Operand(31u), val_hi);
Temp sign = bld.vop2(aco_opcode::v_and_b32, bld.def(v1), Operand(0x80000000u), val_hi);
/* Decide the operation to apply depending on the unbiased exponent. */
Temp exp_lt0 = bld.vopc_e64(aco_opcode::v_cmp_lt_i32, bld.hint_vcc(bld.def(bld.lm)), exponent, Operand(0u));