nir: Undo possible damage caused by rearranging or-compounded float compares

[mesa.git] / src / compiler / nir / nir_lower_gs_intrinsics.c

diff --git a/src/compiler/nir/nir_lower_gs_intrinsics.c b/src/compiler/nir/nir_lower_gs_intrinsics.c
index 406d7f0b5dcc579e85fe5070a768fad59cac8e59..4ddace9cf6a3e6fef301e1a1d6d409173f68a20e 100644 (file)
--- a/src/compiler/nir/nir_lower_gs_intrinsics.c
+++ b/src/compiler/nir/nir_lower_gs_intrinsics.c
@@ -76,19 +76,15 @@ rewrite_emit_vertex(nir_intrinsic_instr *intrin, struct state *state)
    b->cursor = nir_before_instr(&intrin->instr);
    nir_ssa_def *count = nir_load_var(b, state->vertex_count_var);
 
-   nir_ssa_def *max_vertices = nir_imm_int(b, b->shader->info.gs.vertices_out);
+   nir_ssa_def *max_vertices =
+      nir_imm_int(b, b->shader->info.gs.vertices_out);
 
    /* Create: if (vertex_count < max_vertices) and insert it.
     *
     * The new if statement needs to be hooked up to the control flow graph
     * before we start inserting instructions into it.
     */
-   nir_if *if_stmt = nir_if_create(b->shader);
-   if_stmt->condition = nir_src_for_ssa(nir_ilt(b, count, max_vertices));
-   nir_builder_cf_insert(b, &if_stmt->cf_node);
-
-   /* Fill out the new then-block */
-   b->cursor = nir_after_cf_list(&if_stmt->then_list);
+   nir_push_if(b, nir_ilt(b, count, max_vertices));
 
    nir_intrinsic_instr *lowered =
       nir_intrinsic_instr_create(b->shader,
@@ -102,6 +98,8 @@ rewrite_emit_vertex(nir_intrinsic_instr *intrin, struct state *state)
                  nir_iadd(b, count, nir_imm_int(b, 1)),
                  0x1); /* .x */
 
+   nir_pop_if(b, NULL);
+
    nir_instr_remove(&intrin->instr);
 
    state->progress = true;
@@ -133,7 +131,7 @@ rewrite_end_primitive(nir_intrinsic_instr *intrin, struct state *state)
 static bool
 rewrite_intrinsics(nir_block *block, struct state *state)
 {
-   nir_foreach_instr_safe(block, instr) {
+   nir_foreach_instr_safe(instr, block) {
       if (instr->type != nir_instr_type_intrinsic)
          continue;
 
@@ -188,32 +186,27 @@ nir_lower_gs_intrinsics(nir_shader *shader)
    struct state state;
    state.progress = false;
 
-   /* Create the counter variable */
-   nir_variable *var = rzalloc(shader, nir_variable);
-   var->data.mode = nir_var_global;
-   var->type = glsl_uint_type();
-   var->name = "vertex_count";
-   var->constant_initializer = rzalloc(shader, nir_constant); /* initialize to 0 */
+   nir_function_impl *impl = nir_shader_get_entrypoint(shader);
+   assert(impl);
 
-   exec_list_push_tail(&shader->globals, &var->node);
-   state.vertex_count_var = var;
+   nir_builder b;
+   nir_builder_init(&b, impl);
+   state.builder = &b;
 
-   nir_foreach_function(shader, function) {
-      if (function->impl) {
-         nir_builder b;
-         nir_builder_init(&b, function->impl);
-         state.builder = &b;
+   /* Create the counter variable */
+   state.vertex_count_var =
+      nir_local_variable_create(impl, glsl_uint_type(), "vertex_count");
+   /* initialize to 0 */
+   b.cursor = nir_before_cf_list(&impl->body);
+   nir_store_var(&b, state.vertex_count_var, nir_imm_int(&b, 0), 0x1);
 
-         nir_foreach_block_safe(block, function->impl) {
-            rewrite_intrinsics(block, &state);
-         }
+   nir_foreach_block_safe(block, impl)
+      rewrite_intrinsics(block, &state);
 
-         /* This only works because we have a single main() function. */
-         append_set_vertex_count(function->impl->end_block, &state);
+   /* This only works because we have a single main() function. */
+   append_set_vertex_count(impl->end_block, &state);
 
-         nir_metadata_preserve(function->impl, 0);
-      }
-   }
+   nir_metadata_preserve(impl, 0);
 
    return state.progress;
 }