From 0d81b0e18494a80c4326fbc98837842959675869 Mon Sep 17 00:00:00 2001 From: Paul Berry Date: Fri, 29 Jul 2011 15:28:52 -0700 Subject: [PATCH] glsl: Emit function signatures at toplevel, even for built-ins. The ast-to-hir conversion needs to emit function signatures in two circumstances: when a function declaration (or definition) is encountered, and when a built-in function is encountered. To avoid emitting a function signature in an illegal place (such as inside a function), emit_function() checked whether we were inside a function definition, and if so, emitted the signature before the function definition. However, this didn't cover the case of emitting function signatures for built-in functions when those built-in functions are called from inside the constant integer expression that specifies the length of a global array. This failed because when processing an array length, we are emitting IR into a dummy exec_list (see process_array_type() in ast_to_hir.cpp). process_array_type() later checks (via an assertion) that no instructions were emitted to the dummy exec_list, based on the reasonable assumption that we shouldn't need to emit instructions to calculate the value of a constant. This patch changes emit_function() so that it emits function signatures at toplevel in all cases. This partially fixes bug 38625 (https://bugs.freedesktop.org/show_bug.cgi?id=38625). The remainder of the fix is in the patch that follows. Reviewed-by: Kenneth Graunke --- src/glsl/ast.h | 3 +-- src/glsl/ast_function.cpp | 2 +- src/glsl/ast_to_hir.cpp | 31 ++++++++++++++----------------- src/glsl/glsl_parser_extras.h | 6 ++++++ 4 files changed, 22 insertions(+), 20 deletions(-) diff --git a/src/glsl/ast.h b/src/glsl/ast.h index 878f48b2070..d1de2271873 100644 --- a/src/glsl/ast.h +++ b/src/glsl/ast.h @@ -730,7 +730,6 @@ _mesa_ast_field_selection_to_hir(const ast_expression *expr, struct _mesa_glsl_parse_state *state); void -emit_function(_mesa_glsl_parse_state *state, exec_list *instructions, - ir_function *f); +emit_function(_mesa_glsl_parse_state *state, ir_function *f); #endif /* AST_H */ diff --git a/src/glsl/ast_function.cpp b/src/glsl/ast_function.cpp index 8bcf48dfd91..34a82f8ab75 100644 --- a/src/glsl/ast_function.cpp +++ b/src/glsl/ast_function.cpp @@ -125,7 +125,7 @@ match_function_by_name(exec_list *instructions, const char *name, if (f == NULL) { f = new(ctx) ir_function(name); state->symbols->add_global_function(f); - emit_function(state, instructions, f); + emit_function(state, f); } f->add_signature(sig->clone_prototype(f, NULL)); diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp index 7da14611950..a6a0c328314 100644 --- a/src/glsl/ast_to_hir.cpp +++ b/src/glsl/ast_to_hir.cpp @@ -66,6 +66,8 @@ _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state) state->current_function = NULL; + state->toplevel_ir = instructions; + /* Section 4.2 of the GLSL 1.20 specification states: * "The built-in functions are scoped in a scope outside the global scope * users declare global variables in. That is, a shader's global scope, @@ -85,6 +87,8 @@ _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state) ast->hir(instructions, state); detect_recursion_unlinked(state, instructions); + + state->toplevel_ir = NULL; } @@ -2926,23 +2930,16 @@ ast_parameter_declarator::parameters_to_hir(exec_list *ast_parameters, void -emit_function(_mesa_glsl_parse_state *state, exec_list *instructions, - ir_function *f) +emit_function(_mesa_glsl_parse_state *state, ir_function *f) { - /* Emit the new function header */ - if (state->current_function == NULL) { - instructions->push_tail(f); - } else { - /* IR invariants disallow function declarations or definitions nested - * within other function definitions. Insert the new ir_function - * block in the instruction sequence before the ir_function block - * containing the current ir_function_signature. - */ - ir_function *const curr = - const_cast(state->current_function->function()); - - curr->insert_before(f); - } + /* IR invariants disallow function declarations or definitions + * nested within other function definitions. But there is no + * requirement about the relative order of function declarations + * and definitions with respect to one another. So simply insert + * the new ir_function block at the end of the toplevel instruction + * list. + */ + state->toplevel_ir->push_tail(f); } @@ -3069,7 +3066,7 @@ ast_function::hir(exec_list *instructions, return NULL; } - emit_function(state, instructions, f); + emit_function(state, f); } /* Verify the return type of main() */ diff --git a/src/glsl/glsl_parser_extras.h b/src/glsl/glsl_parser_extras.h index 2f4d3cba77f..fc392da5b21 100644 --- a/src/glsl/glsl_parser_extras.h +++ b/src/glsl/glsl_parser_extras.h @@ -129,6 +129,12 @@ struct _mesa_glsl_parse_state { */ class ir_function_signature *current_function; + /** + * During AST to IR conversion, pointer to the toplevel IR + * instruction list being generated. + */ + exec_list *toplevel_ir; + /** Have we found a return statement in this function? */ bool found_return; -- 2.30.2