From 731b94f6f9dcba1996f812e99bdab308493c7693 Mon Sep 17 00:00:00 2001
From: Elizabeth Figura <zfigura@codeweavers.com>
Date: Mon, 4 Aug 2025 21:50:28 -0500
Subject: [PATCH] vkd3d-shader/d3dbc: Lower 1.4 TEXLD.

---
 Makefile.am                        |  1 +
 libs/vkd3d-shader/ir.c             | 34 +++++++++++++++++++++++++++++-
 tests/hlsl/ps1-sampler.shader_test | 30 ++++++++++++++++++++++++++
 3 files changed, 64 insertions(+), 1 deletion(-)
 create mode 100644 tests/hlsl/ps1-sampler.shader_test

diff --git a/Makefile.am b/Makefile.am
index 3102a7829..4e6438d18 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -216,6 +216,7 @@ vkd3d_shader_tests = \
 	tests/hlsl/pow.shader_test \
 	tests/hlsl/precise-modifier.shader_test \
 	tests/hlsl/primitive-id.shader_test \
+	tests/hlsl/ps1-sampler.shader_test \
 	tests/hlsl/rasteriser-ordered-views.shader_test \
 	tests/hlsl/rcp.shader_test \
 	tests/hlsl/reflect.shader_test \
diff --git a/libs/vkd3d-shader/ir.c b/libs/vkd3d-shader/ir.c
index 45c966d5b..0c5344a45 100644
--- a/libs/vkd3d-shader/ir.c
+++ b/libs/vkd3d-shader/ir.c
@@ -1387,6 +1387,36 @@ static enum vkd3d_result vsir_program_lower_sm4_sincos(struct vsir_program *prog
     return VKD3D_OK;
 }
 
+static enum vkd3d_result vsir_program_lower_texld_sm1(struct vsir_program *program,
+        struct vkd3d_shader_instruction *ins, struct vkd3d_shader_message_context *message_context)
+{
+    unsigned int idx = ins->src[0].reg.idx[0].offset;
+    struct vkd3d_shader_src_param *srcs;
+
+    /* texld DST, t# -> sample DST, t#, resource#, sampler# */
+
+    if (ins->src[0].modifiers)
+    {
+        vkd3d_shader_error(message_context, &ins->location, VKD3D_SHADER_ERROR_VSIR_NOT_IMPLEMENTED,
+                "Aborting due to not yet implemented feature: texld source modifier.");
+        return VKD3D_ERROR_NOT_IMPLEMENTED;
+    }
+
+    if (!(srcs = shader_src_param_allocator_get(&program->instructions.src_params, 3)))
+        return VKD3D_ERROR_OUT_OF_MEMORY;
+
+    /* Note we run before I/O normalization. */
+    srcs[0] = ins->src[0];
+    vsir_src_param_init_resource(&srcs[1], idx, idx);
+    vsir_src_param_init_sampler(&srcs[2], idx, idx);
+
+    ins->opcode = VSIR_OP_SAMPLE;
+    ins->src = srcs;
+    ins->src_count = 3;
+
+    return VKD3D_OK;
+}
+
 static enum vkd3d_result vsir_program_lower_texldp(struct vsir_program *program,
         struct vsir_program_iterator *it, unsigned int *tmp_idx)
 {
@@ -1620,7 +1650,9 @@ static enum vkd3d_result vsir_program_lower_d3dbc_instructions(struct vsir_progr
         switch (ins->opcode)
         {
             case VSIR_OP_TEXLD:
-                if (ins->flags == VKD3DSI_TEXLD_PROJECT)
+                if (program->shader_version.major == 1)
+                    ret = vsir_program_lower_texld_sm1(program, ins, message_context);
+                else if (ins->flags == VKD3DSI_TEXLD_PROJECT)
                     ret = vsir_program_lower_texldp(program, &it, &tmp_idx);
                 else
                     ret = vsir_program_lower_texld(program, ins, message_context);
diff --git a/tests/hlsl/ps1-sampler.shader_test b/tests/hlsl/ps1-sampler.shader_test
new file mode 100644
index 000000000..0078d79b7
--- /dev/null
+++ b/tests/hlsl/ps1-sampler.shader_test
@@ -0,0 +1,30 @@
+[require]
+shader model < 3.0
+
+[sampler 0]
+filter point point point
+address wrap wrap wrap
+
+[srv 0]
+size (2d, 2, 2)
+1.0 0.0 0.0 0.0     1.0 1.0 0.0 0.0
+1.0 0.0 1.0 0.0     1.0 1.0 1.0 0.0
+
+[vertex shader]
+void main(inout float4 pos : position, out float4 tex : texcoord)
+{
+    tex = pos + 0.75;
+}
+
+[pixel shader d3dbc-hex]
+% TODO: Convert to assembly or HLSL.
+ffff0104                                                % ps_1_4
+00000042 800f0000 b0e40000                              % texld r0, t0
+0000ffff                                                % end
+
+[test]
+draw quad
+probe (320, 240) f32(1, 1, 1, 0)
+probe (480, 240) f32(1, 0, 1, 0)
+probe (320, 360) f32(1, 1, 0, 0)
+probe (480, 360) f32(1, 0, 0, 0)