From ab0e1e38ab9e8b23602af21d1b43e98afbf80e45 Mon Sep 17 00:00:00 2001 From: Ray Strode Date: Fri, 21 Apr 2017 15:22:14 -0400 Subject: [PATCH] gallivm: correct channel shift logic on big endian lp_build_fetch_rgba_soa fetches a texel from a texture. Part of that process involves first gathering the element together from memory into a packed format, and then breaking out the individual color channels into separate, parallel arrays. The code fails to account for endianess when reading the packed values. This commit attempts to correct the problem by reversing the order the packed values are read on big endian systems. --- src/gallium/auxiliary/gallivm/lp_bld_format_soa.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/src/gallium/auxiliary/gallivm/lp_bld_format_soa.c b/src/gallium/auxiliary/gallivm/lp_bld_format_soa.c index 98eb694..22c19b1 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_format_soa.c +++ b/src/gallium/auxiliary/gallivm/lp_bld_format_soa.c @@ -650,7 +650,13 @@ lp_build_fetch_rgba_soa(struct gallivm_state *gallivm, for (i = 0; i < format_desc->nr_channels; i++) { struct util_format_channel_description chan_desc = format_desc->channel[i]; unsigned blockbits = type.width; - unsigned vec_nr = chan_desc.shift / type.width; + unsigned vec_nr; + +#ifdef PIPE_ARCH_BIG_ENDIAN + vec_nr = (format_desc->block.bits - (chan_desc.shift + chan_desc.size)) / type.width; +#else + vec_nr = chan_desc.shift / type.width; +#endif chan_desc.shift %= type.width; output[i] = lp_build_extract_soa_chan(&bld, -- 1.8.3.1