<div dir="ltr"><div>Reviewed-by: Marek Olšák <<a href="mailto:marek.olsak@amd.com" target="_blank">marek.olsak@amd.com</a>></div><div> </div><div>Marek </div></div> <div class="gmail_quote"><div dir="ltr">On Mon, Jan 7, 2019 at 1:42 PM Mario Kleiner <<a href="mailto:mario.kleiner.de@gmail.com" target="_blank">mario.kleiner.de@gmail.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">With Mesa 18.1, commit be973ed21f6e, si_llvm_load_input_vs() changed the number of source 32-bit wide dword components used for fetching vertex attributes into the vertex shader from a constant 4 to a variable num_channels number, depending on input data format, with some special case handling for input data formats like 64-Bit doubles. In the case of a GL_DOUBLE input data format with one or two components though, e.g, submitted via ... a) glTexCoordPointer(1, GL_DOUBLE, 0, buffer); b) glTexCoordPointer(2, GL_DOUBLE, 0, buffer); ... the input format would be SI_FIX_FETCH_RG_64_FLOAT, but no special case handling was implemented for that case, so in the default path the number of 32-bit dwords would be set to the number of float input components derived from info->input_usage_mask. This ends with corrupted input to the vertex shader, because fetching a 64-bit double from the vbo requires fetching two 32-bit dwords instead of 1, and fetching a two double input requires 4 dword fetches instead of 2, so in these cases the vertex shader receives incomplete/truncated input data: a) float v = gl_MultiTexCoord0.x; -> v.x is corrupted. b) vec2 v = gl_MultiTexCoord0.xy; -> v.x is assigned correctly, but v.y is corrupted. This happens with the standard TGSI IR compiled shaders. Under NIR with R600_DEBUG=nir, we got correct behavior because the current radeonsi nir code always assigns info->input_usage_mask = TGSI_WRITEMASK_XYZW, thereby always fetches 4 dwords regardless of what the shader actually needs. Fix this by properly assigning 2 or 4 dword fetches for one or two component GL_DOUBLE input. Fixes: be973ed21f6e ("radeonsi: load the right number of components for VS inputs and TBOs") Signed-off-by: Mario Kleiner <<a href="mailto:mario.kleiner.de@gmail.com" target="_blank">mario.kleiner.de@gmail.com</a>> Cc: <a href="mailto:mesa-stable@lists.freedesktop.org" target="_blank">mesa-stable@lists.freedesktop.org</a> Cc: Marek Olšák <<a href="mailto:marek.olsak@amd.com" target="_blank">marek.olsak@amd.com</a>> --- src/gallium/drivers/radeonsi/si_shader.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c index 190edce..14bb875 100644 --- a/src/gallium/drivers/radeonsi/si_shader.c +++ b/src/gallium/drivers/radeonsi/si_shader.c @@ -561,6 +561,14 @@ void si_llvm_load_input_vs( /* Do multiple loads for special formats. */ switch (fix_fetch) { + case SI_FIX_FETCH_RG_64_FLOAT: + num_fetches = 1; /* 1 2-dword or 4-dword load */ + fetch_stride = 0; + if (util_last_bit(info->input_usage_mask[input_index]) >= 2) + num_channels = 4; /* 2 doubles in 4 dwords */ + else + num_channels = 2; /* 1 double in 2 dwords */ + break; case SI_FIX_FETCH_RGB_64_FLOAT: num_fetches = 3; /* 3 2-dword loads */ fetch_stride = 8; -- 2.7.4 _______________________________________________ mesa-stable mailing list <a href="mailto:mesa-stable@lists.freedesktop.org" target="_blank">mesa-stable@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-stable" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/mesa-stable</a> </blockquote></div>