spirv: Change spirv_to_nir() to return a nir_shader

spirv_to_nir() returned the nir_function corresponding to the
entrypoint, as a way to identify it.  There's now a bool is_entrypoint
in nir_function and also a helper function to get the entry_point from
a nir_shader.

The return type reflects better what the function name suggests.  It
also helps drivers avoid the mistake of reusing internal shader
references after running NIR_PASS on it.  When using NIR_TEST_CLONE or
NIR_TEST_SERIALIZE, those would be invalidated right in the first pass
executed.

Reviewed-by: Bas Nieuwenhuizen <[email protected]>

1 files changed, 2 insertions, 5 deletions

diff --git a/src/mesa/main/glspirv.c b/src/mesa/main/glspirv.c
index 8d1ac9b5072..bb5a3f7452b 100644
--- a/src/mesa/main/glspirv.c
+++ b/src/mesa/main/glspirv.c
@@ -186,8 +186,6 @@ _mesa_spirv_to_nir(struct gl_context *ctx,
                    gl_shader_stage stage,
                    const nir_shader_compiler_options *options)
 {
-   nir_shader *nir = NULL;
-
    struct gl_linked_shader *linked_shader = prog->_LinkedShaders[stage];
    assert (linked_shader);
 
@@ -217,7 +215,7 @@ _mesa_spirv_to_nir(struct gl_context *ctx,
       .caps = ctx->Const.SpirVCapabilities
    };
 
-   nir_function *entry_point =
+   nir_shader *nir =
       spirv_to_nir((const uint32_t *) &spirv_module->Binary[0],
                    spirv_module->Length / 4,
                    spec_entries, spirv_data->NumSpecializationConstants,
@@ -226,8 +224,7 @@ _mesa_spirv_to_nir(struct gl_context *ctx,
                    options);
    free(spec_entries);
 
-   assert (entry_point);
-   nir = entry_point->shader;
+   assert(nir);
    assert(nir->info.stage == stage);
 
    nir->options = options;