nir/builder: Add an init function that creates a simple shader for you

A hugely common case when using nir_builder is to have a shader with a
single function called main.  This adds a helper that gives you just that.
This commit also makes us use it in the NIR control-flow unit tests as well
as tgsi_to_nir and prog_to_nir.

Reviewed-by: Eric Anholt <[email protected]>
Reviewed-by: Connor Abbott <[email protected]>
Acked-by: Kenneth Graunke <[email protected]>

1 files changed, 3 insertions, 10 deletions

diff --git a/src/mesa/program/prog_to_nir.c b/src/mesa/program/prog_to_nir.c
index c5d4f273fc8..ce6f6997d2f 100644
--- a/src/mesa/program/prog_to_nir.c
+++ b/src/mesa/program/prog_to_nir.c
@@ -1082,11 +1082,11 @@ prog_to_nir(const struct gl_program *prog,
    c = rzalloc(NULL, struct ptn_compile);
    if (!c)
       return NULL;
-   s = nir_shader_create(NULL, stage, options);
-   if (!s)
-      goto fail;
    c->prog = prog;
 
+   nir_builder_init_simple_shader(&c->build, NULL, stage, options);
+   s = c->build.shader;
+
    if (prog->Parameters->NumParameters > 0) {
       c->parameters = rzalloc(s, nir_variable);
       c->parameters->type =
@@ -1097,13 +1097,6 @@ prog_to_nir(const struct gl_program *prog,
       exec_list_push_tail(&s->uniforms, &c->parameters->node);
    }
 
-   nir_function *func = nir_function_create(s, "main");
-   nir_function_impl *impl = nir_function_impl_create(func);
-
-   c->build.shader = s;
-   c->build.impl = impl;
-   c->build.cursor = nir_after_cf_list(&impl->body);
-
    setup_registers_and_variables(c);
    if (unlikely(c->error))
       goto fail;