ir3: add mergedregs to ir3_compiler

Storing it only in ir3_shader is sometimes inconvenient because it's not
available everywhere.

Signed-off-by: Job Noorman <job@noorman.info>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34108>

src/freedreno/ir3/ir3_compiler.c

@@ -239,6 +239,7 @@ ir3_compiler_create(struct fd_device *dev, const struct fd_dev_id *dev_id,
       compiler->reading_shading_rate_requires_smask_quirk =
          dev_info->a7xx.reading_shading_rate_requires_smask_quirk;
       compiler->has_alias_rt = dev_info->a7xx.has_alias_rt;
+      compiler->mergedregs = true;
 
       if (compiler->gen >= 7) {
          compiler->has_alias_tex = true;

src/freedreno/ir3/ir3_compiler.h

@@ -110,6 +110,9 @@ struct ir3_compiler {
    /* on a650, vertex shader <-> tess control io uses LDL/STL */
    bool tess_use_shared;
 
+   /* Whether full and half regs are merged. */
+   bool mergedregs;
+
    /* The maximum number of constants, in vec4's, across the entire graphics
     * pipeline.
     */

src/freedreno/ir3/ir3_shader.c

@@ -511,7 +511,7 @@ alloc_variant(struct ir3_shader *shader, const struct ir3_shader_key *key,
    v->key = *key;
    v->type = shader->type;
    v->compiler = shader->compiler;
-   v->mergedregs = shader->compiler->gen >= 6;
+   v->mergedregs = shader->compiler->mergedregs;
    v->stream_output = shader->stream_output;
 
    v->name = ralloc_strdup(v, shader->nir->info.name);