tgsi: split tgsi_util_get_texture_coord_dim() function into two

It was kind of overloaded, returning two different things.  Now get
the index of the shadow reference src register with a new
tgsi_util_get_shadow_ref_src_index() function.

To verify the new code, I added some temp/debug code which looped
over all TGSI_TEXTURE_x values, calling the old function and new and
checking that the returned indexes matched.

Also tested piglit "shadow" tests with softpipe/llvmpipe.
No testing of ilo and radeonsi changes.

Reviewed-by: Dave Airlie <airlied@redhat.com>

6 files changed, 46 insertions, 47 deletions

diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.c b/src/gallium/auxiliary/tgsi/tgsi_exec.c
index 53d5937b2d..e7f080eb12 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_exec.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_exec.c
@@ -2054,7 +2054,8 @@ exec_tex(struct tgsi_exec_machine *mach,
    assert(modifier != TEX_MODIFIER_LEVEL_ZERO);
    assert(inst->Texture.Texture != TGSI_TEXTURE_BUFFER);
 
-   dim = tgsi_util_get_texture_coord_dim(inst->Texture.Texture, &shadow_ref);
+   dim = tgsi_util_get_texture_coord_dim(inst->Texture.Texture);
+   shadow_ref = tgsi_util_get_shadow_ref_src_index(inst->Texture.Texture);
 
    assert(dim <= 4);
    if (shadow_ref >= 0)
@@ -2153,7 +2154,7 @@ exec_lodq(struct tgsi_exec_machine *mach,
    union tgsi_exec_channel r[2];
 
    unit = fetch_sampler_unit(mach, inst, 1);
-   dim = tgsi_util_get_texture_coord_dim(inst->Texture.Texture, NULL);
+   dim = tgsi_util_get_texture_coord_dim(inst->Texture.Texture);
    assert(dim <= Elements(coords));
    /* fetch coordinates */
    for (i = 0; i < dim; i++) {
diff --git a/src/gallium/auxiliary/tgsi/tgsi_util.c b/src/gallium/auxiliary/tgsi/tgsi_util.c
index 5fff3f0787..fbe29626a7 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_util.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_util.c
@@ -375,10 +375,8 @@ tgsi_util_get_src_from_ind(const struct tgsi_ind_register *reg)
  * sample index.
  */
 int
-tgsi_util_get_texture_coord_dim(int tgsi_tex, int *shadow_or_sample)
+tgsi_util_get_texture_coord_dim(unsigned tgsi_tex)
 {
-   int dim;
-
    /*
     * Depending on the texture target, (src0.xyzw, src1.x) is interpreted
     * differently:
@@ -407,8 +405,7 @@ tgsi_util_get_texture_coord_dim(int tgsi_tex, int *shadow_or_sample)
    case TGSI_TEXTURE_BUFFER:
    case TGSI_TEXTURE_1D:
    case TGSI_TEXTURE_SHADOW1D:
-      dim = 1;
-      break;
+      return 1;
    case TGSI_TEXTURE_2D:
    case TGSI_TEXTURE_RECT:
    case TGSI_TEXTURE_1D_ARRAY:
@@ -416,52 +413,48 @@ tgsi_util_get_texture_coord_dim(int tgsi_tex, int *shadow_or_sample)
    case TGSI_TEXTURE_SHADOWRECT:
    case TGSI_TEXTURE_SHADOW1D_ARRAY:
    case TGSI_TEXTURE_2D_MSAA:
-      dim = 2;
-      break;
+      return 2;
    case TGSI_TEXTURE_3D:
    case TGSI_TEXTURE_CUBE:
    case TGSI_TEXTURE_2D_ARRAY:
    case TGSI_TEXTURE_SHADOWCUBE:
    case TGSI_TEXTURE_SHADOW2D_ARRAY:
    case TGSI_TEXTURE_2D_ARRAY_MSAA:
-      dim = 3;
-      break;
+      return 3;
    case TGSI_TEXTURE_CUBE_ARRAY:
    case TGSI_TEXTURE_SHADOWCUBE_ARRAY:
-      dim = 4;
-      break;
+      return 4;
    default:
       assert(!"unknown texture target");
-      dim = 0;
-      break;
+      return 0;
    }
+}
 
-   if (shadow_or_sample) {
-      switch (tgsi_tex) {
-      case TGSI_TEXTURE_SHADOW1D:
-         /* there is a gap */
-         *shadow_or_sample = 2;
-         break;
-      case TGSI_TEXTURE_SHADOW2D:
-      case TGSI_TEXTURE_SHADOWRECT:
-      case TGSI_TEXTURE_SHADOWCUBE:
-      case TGSI_TEXTURE_SHADOW1D_ARRAY:
-      case TGSI_TEXTURE_SHADOW2D_ARRAY:
-      case TGSI_TEXTURE_SHADOWCUBE_ARRAY:
-         *shadow_or_sample = dim;
-         break;
-      case TGSI_TEXTURE_2D_MSAA:
-      case TGSI_TEXTURE_2D_ARRAY_MSAA:
-         *shadow_or_sample = 3;
-         break;
-      default:
-         /* no shadow nor sample */
-         *shadow_or_sample = -1;
-         break;
-      }
-   }
 
-   return dim;
+/**
+ * Given a TGSI_TEXTURE_x target, return the src register index for the
+ * shadow reference coordinate.
+ */
+int
+tgsi_util_get_shadow_ref_src_index(unsigned tgsi_tex)
+{
+   switch (tgsi_tex) {
+   case TGSI_TEXTURE_SHADOW1D:
+   case TGSI_TEXTURE_SHADOW2D:
+   case TGSI_TEXTURE_SHADOWRECT:
+   case TGSI_TEXTURE_SHADOW1D_ARRAY:
+      return 2;
+   case TGSI_TEXTURE_SHADOWCUBE:
+   case TGSI_TEXTURE_SHADOW2D_ARRAY:
+   case TGSI_TEXTURE_2D_MSAA:
+   case TGSI_TEXTURE_2D_ARRAY_MSAA:
+      return 3;
+   case TGSI_TEXTURE_SHADOWCUBE_ARRAY:
+      return 4;
+   default:
+      /* no shadow nor sample */
+      return -1;
+   }
 }
 
 
diff --git a/src/gallium/auxiliary/tgsi/tgsi_util.h b/src/gallium/auxiliary/tgsi/tgsi_util.h
index 6175d95fcd..3a049ee566 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_util.h
+++ b/src/gallium/auxiliary/tgsi/tgsi_util.h
@@ -80,7 +80,10 @@ struct tgsi_src_register
 tgsi_util_get_src_from_ind(const struct tgsi_ind_register *reg);
 
 int
-tgsi_util_get_texture_coord_dim(int tgsi_tex, int *shadow_or_sample);
+tgsi_util_get_texture_coord_dim(unsigned tgsi_tex);
+
+int
+tgsi_util_get_shadow_ref_src_index(unsigned tgsi_tex);
 
 boolean
 tgsi_is_shadow_target(unsigned target);
diff --git a/src/gallium/drivers/ilo/shader/ilo_shader_fs.c b/src/gallium/drivers/ilo/shader/ilo_shader_fs.c
index f46126e842..6c8f1b5222 100644
--- a/src/gallium/drivers/ilo/shader/ilo_shader_fs.c
+++ b/src/gallium/drivers/ilo/shader/ilo_shader_fs.c
@@ -740,7 +740,9 @@ fs_prepare_tgsi_sampling(struct fs_compile_context *fcc,
       break;
    }
 
-   num_coords = tgsi_util_get_texture_coord_dim(inst->tex.target, &ref_pos);
+   num_coords = tgsi_util_get_texture_coord_dim(inst->tex.target);
+   ref_pos = tgsi_util_get_shadow_ref_src_index(inst->tex.target);
+
    tsrc_transpose(inst->src[0], coords);
    bias_or_lod = tsrc_null();
    ref_or_si = tsrc_null();
diff --git a/src/gallium/drivers/ilo/shader/ilo_shader_vs.c b/src/gallium/drivers/ilo/shader/ilo_shader_vs.c
index 0df0afc706..2b46d44f5b 100644
--- a/src/gallium/drivers/ilo/shader/ilo_shader_vs.c
+++ b/src/gallium/drivers/ilo/shader/ilo_shader_vs.c
@@ -407,7 +407,8 @@ vs_prepare_tgsi_sampling(struct vs_compile_context *vcc,
    num_derivs = 0;
    sampler_src = 1;
 
-   num_coords = tgsi_util_get_texture_coord_dim(inst->tex.target, &ref_pos);
+   num_coords = tgsi_util_get_texture_coord_dim(inst->tex.target);
+   ref_pos = tgsi_util_get_shadow_ref_src_index(inst->tex.target);
 
    /* extract the parameters */
    switch (inst->opcode) {
diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 9eb531f8d8..4176e9f1ce 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -2874,8 +2874,7 @@ static LLVMValueRef image_fetch_coords(
 	struct gallivm_state *gallivm = bld_base->base.gallivm;
 	LLVMBuilderRef builder = gallivm->builder;
 	unsigned target = inst->Memory.Texture;
-	int sample;
-	unsigned num_coords = tgsi_util_get_texture_coord_dim(target, &sample);
+	unsigned num_coords = tgsi_util_get_texture_coord_dim(target);
 	LLVMValueRef coords[4];
 	LLVMValueRef tmp;
 	int chan;
@@ -3387,8 +3386,8 @@ static void tex_fetch_args(
 	unsigned target = inst->Texture.Texture;
 	LLVMValueRef coords[5], derivs[6];
 	LLVMValueRef address[16];
-	int ref_pos;
-	unsigned num_coords = tgsi_util_get_texture_coord_dim(target, &ref_pos);
+	unsigned num_coords = tgsi_util_get_texture_coord_dim(target);
+	int ref_pos = tgsi_util_get_shadow_ref_src_index(target);
 	unsigned count = 0;
 	unsigned chan;
 	unsigned num_deriv_channels = 0;