From 06e724c7b4ade29868531edb20900859f566a077 Mon Sep 17 00:00:00 2001 From: Roland Scheidegger Date: Fri, 2 Mar 2018 03:00:41 +0100 Subject: [PATCH] tgsi/scan: use wrap-around shift behavior explicitly for file_mask The comment said it will only represent the lowest 32 regs. This was not entirely true in practice, since at least on x86 you'll get masked shifts (unless the compiler could recognize it already and toss it out). It turns out this actually works out alright (presumably noone uses it for temp regs) when increasing max sampler views, so make that behavior explicit. Albeit it feels a bit hacky (but in any case, explicit behavior there is better than undefined behavior). Reviewed-by: Jose Fonseca Reviewed-by: Brian Paul --- src/gallium/auxiliary/tgsi/tgsi_scan.c | 7 +++++-- src/gallium/drivers/llvmpipe/lp_state_fs.c | 7 ++++++- src/gallium/drivers/swr/swr_shader.cpp | 2 +- 3 files changed, 12 insertions(+), 4 deletions(-) diff --git a/src/gallium/auxiliary/tgsi/tgsi_scan.c b/src/gallium/auxiliary/tgsi/tgsi_scan.c index c35eff2..4a2b354 100644 --- a/src/gallium/auxiliary/tgsi/tgsi_scan.c +++ b/src/gallium/auxiliary/tgsi/tgsi_scan.c @@ -585,8 +585,11 @@ scan_declaration(struct tgsi_shader_info *info, int buffer; unsigned index, target, type; - /* only first 32 regs will appear in this bitfield */ - info->file_mask[file] |= (1 << reg); + /* + * only first 32 regs will appear in this bitfield, if larger + * bits will wrap around. + */ + info->file_mask[file] |= (1u << (reg & 31)); info->file_count[file]++; info->file_max[file] = MAX2(info->file_max[file], (int)reg); diff --git a/src/gallium/drivers/llvmpipe/lp_state_fs.c b/src/gallium/drivers/llvmpipe/lp_state_fs.c index 603fd84..66645b0 100644 --- a/src/gallium/drivers/llvmpipe/lp_state_fs.c +++ b/src/gallium/drivers/llvmpipe/lp_state_fs.c @@ -3323,7 +3323,12 @@ make_variant_key(struct llvmpipe_context *lp, if (shader->info.base.file_max[TGSI_FILE_SAMPLER_VIEW] != -1) { key->nr_sampler_views = shader->info.base.file_max[TGSI_FILE_SAMPLER_VIEW] + 1; for(i = 0; i < key->nr_sampler_views; ++i) { - if(shader->info.base.file_mask[TGSI_FILE_SAMPLER_VIEW] & (1 << i)) { + /* + * Note sview may exceed what's representable by file_mask. + * This will still work, the only downside is that not actually + * used views may be included in the shader key. + */ + if(shader->info.base.file_mask[TGSI_FILE_SAMPLER_VIEW] & (1u << (i & 31))) { lp_sampler_static_texture_state(&key->state[i].texture_state, lp->sampler_views[PIPE_SHADER_FRAGMENT][i]); } diff --git a/src/gallium/drivers/swr/swr_shader.cpp b/src/gallium/drivers/swr/swr_shader.cpp index e5fb679..477fa7f 100644 --- a/src/gallium/drivers/swr/swr_shader.cpp +++ b/src/gallium/drivers/swr/swr_shader.cpp @@ -98,7 +98,7 @@ swr_generate_sampler_key(const struct lp_tgsi_info &info, key.nr_sampler_views = info.base.file_max[TGSI_FILE_SAMPLER_VIEW] + 1; for (unsigned i = 0; i < key.nr_sampler_views; i++) { - if (info.base.file_mask[TGSI_FILE_SAMPLER_VIEW] & (1 << i)) { + if (info.base.file_mask[TGSI_FILE_SAMPLER_VIEW] & (1u << (i & 31))) { const struct pipe_sampler_view *view = ctx->sampler_views[shader_type][i]; lp_sampler_static_texture_state( -- 2.7.4