Francisco Casas : vkd3d-shader/hlsl: Use aoffimmis when writing gather resource loads.

[Alexandre Julliard]

Module: vkd3d
Branch: master
Commit: 18adf0d726a3134e6c30bea1518fe96ea0285374
URL:    https://gitlab.winehq.org/wine/vkd3d/-/commit/18adf0d726a3134e6c30bea1518fe9...

Author: Francisco Casas 
Date:   Thu Nov 17 18:02:39 2022 -0300

vkd3d-shader/hlsl: Use aoffimmis when writing gather resource loads.

If the offset of a gather resource load can be represented as an
aoffimmi (vectori of ints from -8 to 7), use one.
This is of particular importance for 4.0 profiles, where this is the only
valid way of representing offsets for this operation.

---

libs/vkd3d-shader/hlsl_sm4.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/libs/vkd3d-shader/hlsl_sm4.c b/libs/vkd3d-shader/hlsl_sm4.c
index 06035a63..62266780 100644
--- a/libs/vkd3d-shader/hlsl_sm4.c
+++ b/libs/vkd3d-shader/hlsl_sm4.c
@@ -2154,11 +2154,19 @@ static void write_sm4_gather(struct hlsl_ctx *ctx, struct vkd3d_bytecode_buffer

sm4_src_from_node(&instr.srcs[instr.src_count++], coords, VKD3DSP_WRITEMASK_ALL);

-    /* FIXME: Use an aoffimmi modifier if possible. */
     if (texel_offset)
     {
-        instr.opcode = VKD3D_SM5_OP_GATHER4_PO;
-        sm4_src_from_node(&instr.srcs[instr.src_count++], texel_offset, VKD3DSP_WRITEMASK_ALL);
+        if (!encode_texel_offset_as_aoffimmi(&instr, texel_offset))
+        {
+            if (ctx->profile->major_version < 5)
+            {
+                hlsl_error(ctx, &texel_offset->loc, VKD3D_SHADER_ERROR_HLSL_INVALID_TEXEL_OFFSET,
+                    "Offset must resolve to integer literal in the range -8 to 7 for profiles < 5.");
+                return;
+            }
+            instr.opcode = VKD3D_SM5_OP_GATHER4_PO;
+            sm4_src_from_node(&instr.srcs[instr.src_count++], texel_offset, VKD3DSP_WRITEMASK_ALL);
+        }
     }

sm4_src_from_deref(ctx, &instr.srcs[instr.src_count++], resource, resource_type, instr.dsts[0].writemask);