diff options
| author | Ian Romanick <ian.d.romanick@intel.com> | 2021-10-28 17:33:02 -0700 |
|---|---|---|
| committer | Dylan Baker <dylan.c.baker@intel.com> | 2022-02-24 14:56:50 -0800 |
| commit | 2b73963911f716e333c5807ade72f960881e9151 (patch) | |
| tree | a84668301b3f96543e39f85df87433818d692469 | |
| parent | 8d4287079824b07f21fc5e1137591a4d87fb408e (diff) | |
spriv: Produce correct result for GLSLstd450Step with NaN
NOTE: This commit needs "nir: All set-on-comparison opcodes can take all
float types" or regressions will occur in other Vulkan SPIR-V tests.
No shader-db changes on any Intel platform.
NOTE: This commit depends on "nir: All set-on-comparison opcodes can
take all float types".
v2: Fix handling 16-bit (and presumably 64-bit) values.
About 280 shaders in Talos are hurt by a few instructions, and a couple
shaders in Doom 2016 are hurt by a few instructions.
Tiger Lake
Instructions in all programs: 159893290 -> 159895026 (+0.0%)
SENDs in all programs: 6936431 -> 6936431 (+0.0%)
Loops in all programs: 38385 -> 38385 (+0.0%)
Cycles in all programs: 7019260087 -> 7019254134 (-0.0%)
Spills in all programs: 101389 -> 101389 (+0.0%)
Fills in all programs: 131532 -> 131532 (+0.0%)
Ice Lake
Instructions in all programs: 143624235 -> 143625691 (+0.0%)
SENDs in all programs: 6980289 -> 6980289 (+0.0%)
Loops in all programs: 38383 -> 38383 (+0.0%)
Cycles in all programs: 8440083238 -> 8440090702 (+0.0%)
Spills in all programs: 102246 -> 102246 (+0.0%)
Fills in all programs: 131908 -> 131908 (+0.0%)
Skylake
Instructions in all programs: 134185495 -> 134186618 (+0.0%)
SENDs in all programs: 6938790 -> 6938790 (+0.0%)
Loops in all programs: 38356 -> 38356 (+0.0%)
Cycles in all programs: 8222366923 -> 8222365826 (-0.0%)
Spills in all programs: 98821 -> 98821 (+0.0%)
Fills in all programs: 125218 -> 125218 (+0.0%)
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Fixes: 1feeee9cf47 ("nir/spirv: Add initial support for GLSL 4.50 builtins")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13999>
(cherry picked from commit 75ef5991f5af06997551dabc053300261e32ca40)
| -rw-r--r-- | .pick_status.json | 2 | ||||
| -rw-r--r-- | src/compiler/spirv/vtn_glsl450.c | 23 |
2 files changed, 22 insertions, 3 deletions
diff --git a/.pick_status.json b/.pick_status.json index 82e7b523f5c..42cad30f9f1 100644 --- a/.pick_status.json +++ b/.pick_status.json @@ -112,7 +112,7 @@ "description": "spriv: Produce correct result for GLSLstd450Step with NaN", "nominated": true, "nomination_type": 1, - "resolution": 0, + "resolution": 1, "main_sha": null, "because_sha": "1feeee9cf476010f72cb973480f67de0764e6a90" }, diff --git a/src/compiler/spirv/vtn_glsl450.c b/src/compiler/spirv/vtn_glsl450.c index d6ab4c03d21..d596c251548 100644 --- a/src/compiler/spirv/vtn_glsl450.c +++ b/src/compiler/spirv/vtn_glsl450.c @@ -352,9 +352,28 @@ handle_glsl450_alu(struct vtn_builder *b, enum GLSLstd450 entrypoint, break; } - case GLSLstd450Step: - dest->def = nir_sge(nb, src[1], src[0]); + case GLSLstd450Step: { + /* The SPIR-V Extended Instructions for GLSL spec says: + * + * Result is 0.0 if x < edge; otherwise result is 1.0. + * + * Here src[1] is x, and src[0] is edge. The direct implementation is + * + * bcsel(src[1] < src[0], 0.0, 1.0) + * + * This is effectively b2f(!(src1 < src0)). Previously this was + * implemented using sge(src1, src0), but that produces incorrect + * results for NaN. Instead, we use the identity b2f(!x) = 1 - b2f(x). + */ + const bool exact = nb->exact; + nb->exact = true; + + nir_ssa_def *cmp = nir_slt(nb, src[1], src[0]); + + nb->exact = exact; + dest->def = nir_fsub(nb, nir_imm_floatN_t(nb, 1.0f, cmp->bit_size), cmp); break; + } case GLSLstd450Length: dest->def = nir_fast_length(nb, src[0]); |