From 66f4ac988d5053c9782d1390541b04f4d9c50078 Mon Sep 17 00:00:00 2001 From: Ian Romanick Date: Wed, 29 Jun 2011 14:52:10 -0700 Subject: [PATCH] linker: Only over-ride built-ins when a prototype has been seen The GLSL spec says: "If a built-in function is redeclared in a shader (i.e., a prototype is visible) before a call to it, then the linker will only attempt to resolve that call within the set of shaders that are linked with it." This patch enforces this behavior. When a function call is processed a flag is set in the ir_call to indicate whether the previously seen prototype is the built-in or not. At link time a call will only bind to an instance of a function that matches the "want built-in" setting in the ir_call. This has the odd side effect that first call to abs() in the shader below will call the built-in and the second will not: float foo(float x) { return abs(x); } float abs(float x) { return -x; } float bar(float x) { return abs(x); } This seems insane, but it matches what the spec says. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=31744 --- src/glsl/ir.h | 4 ++++ src/glsl/link_functions.cpp | 22 +++++++++++++++++----- 2 files changed, 21 insertions(+), 5 deletions(-) diff --git a/src/glsl/ir.h b/src/glsl/ir.h index 42a3936976a..80ad3dd295e 100644 --- a/src/glsl/ir.h +++ b/src/glsl/ir.h @@ -991,6 +991,7 @@ public: assert(callee->return_type != NULL); type = callee->return_type; actual_parameters->move_nodes_to(& this->actual_parameters); + this->use_builtin = callee->is_builtin; } virtual ir_call *clone(void *mem_ctx, struct hash_table *ht) const; @@ -1054,6 +1055,9 @@ public: /* List of ir_rvalue of paramaters passed in this call. */ exec_list actual_parameters; + /** Should this call only bind to a built-in function? */ + bool use_builtin; + private: ir_call() : callee(NULL) diff --git a/src/glsl/link_functions.cpp b/src/glsl/link_functions.cpp index ae8818be871..7ba760daa1a 100644 --- a/src/glsl/link_functions.cpp +++ b/src/glsl/link_functions.cpp @@ -31,7 +31,8 @@ static ir_function_signature * find_matching_signature(const char *name, const exec_list *actual_parameters, - gl_shader **shader_list, unsigned num_shaders); + gl_shader **shader_list, unsigned num_shaders, + bool use_builtin); class call_link_visitor : public ir_hierarchical_visitor { public: @@ -75,7 +76,8 @@ public: * final linked shader. If it does, use it as the target of the call. */ ir_function_signature *sig = - find_matching_signature(name, &callee->parameters, &linked, 1); + find_matching_signature(name, &callee->parameters, &linked, 1, + ir->use_builtin); if (sig != NULL) { ir->set_callee(sig); return visit_continue; @@ -85,7 +87,7 @@ public: * linked. If it's not found there, return an error. */ sig = find_matching_signature(name, &ir->actual_parameters, shader_list, - num_shaders); + num_shaders, ir->use_builtin); if (sig == NULL) { /* FINISHME: Log the full signature of unresolved function. */ @@ -110,7 +112,9 @@ public: ir_function_signature *linked_sig = f->exact_matching_signature(&callee->parameters); - if (linked_sig == NULL) { + if ((linked_sig == NULL) + || ((linked_sig != NULL) + && (linked_sig->is_builtin != ir->use_builtin))) { linked_sig = new(linked) ir_function_signature(callee->return_type); f->add_signature(linked_sig); } @@ -241,7 +245,8 @@ private: */ ir_function_signature * find_matching_signature(const char *name, const exec_list *actual_parameters, - gl_shader **shader_list, unsigned num_shaders) + gl_shader **shader_list, unsigned num_shaders, + bool use_builtin) { for (unsigned i = 0; i < num_shaders; i++) { ir_function *const f = shader_list[i]->symbols->get_function(name); @@ -254,6 +259,13 @@ find_matching_signature(const char *name, const exec_list *actual_parameters, if ((sig == NULL) || !sig->is_defined) continue; + /* If this function expects to bind to a built-in function and the + * signature that we found isn't a built-in, keep looking. Also keep + * looking if we expect a non-built-in but found a built-in. + */ + if (use_builtin != sig->is_builtin) + continue; + return sig; } -- 2.11.0