From 532c2d30850908b75f4b0ad0aa5fa7ce88f8202d Mon Sep 17 00:00:00 2001 From: Ian Romanick Date: Thu, 15 Jul 2010 19:28:32 -0700 Subject: [PATCH] linker: look up function signatures during linking instead of using callee Instead of using ir_call::callee, search for the signature in the linked shader. This will allow resolving calls from functions imported from other shaders. The ir_call::callee pointer in the imported function will still reference a signature in the original shader. --- src/glsl/link_functions.cpp | 83 ++++++++++++++++++++++++++++++++------------- 1 file changed, 59 insertions(+), 24 deletions(-) diff --git a/src/glsl/link_functions.cpp b/src/glsl/link_functions.cpp index 28e56cb..721bec6 100644 --- a/src/glsl/link_functions.cpp +++ b/src/glsl/link_functions.cpp @@ -43,36 +43,43 @@ find_matching_signature(const char *name, const exec_list *actual_parameters, class call_link_visitor : public ir_hierarchical_visitor { public: - call_link_visitor(gl_shader_program *prog, gl_shader **shader_list, - unsigned num_shaders) + call_link_visitor(gl_shader_program *prog, gl_shader *linked, + gl_shader **shader_list, unsigned num_shaders) { this->prog = prog; this->shader_list = shader_list; this->num_shaders = num_shaders; this->success = true; + this->linked = linked; } virtual ir_visitor_status visit_enter(ir_call *ir) { - /* If the function call references a function signature that does not - * have a definition, try to find the definition in one of the other - * shaders. + /* If ir is an ir_call from a function that was imported from another + * shader callee will point to an ir_function_signature in the original + * shader. In this case the function signature MUST NOT BE MODIFIED. + * Doing so will modify the original shader. This may prevent that + * shader from being linkable in other programs. */ - ir_function_signature *callee = - const_cast(ir->get_callee()); + const ir_function_signature *const callee = ir->get_callee(); assert(callee != NULL); - - if (callee->is_defined) - /* FINISHME: Do children need to be processed, or are all parameters - * FINISHME: with function calls already flattend? - */ - return visit_continue; - const char *const name = callee->function_name(); + /* Determine if the requested function signature already exists in the + * final linked shader. If it does, use it as the target of the call. + */ ir_function_signature *sig = - find_matching_signature(name, &ir->actual_parameters, shader_list, - num_shaders); + find_matching_signature(name, &callee->parameters, &linked, 1); + if (sig != NULL) { + ir->set_callee(sig); + return visit_continue; + } + + /* Try to find the signature in one of the other shaders that is being + * linked. If it's not found there, return an error. + */ + sig = find_matching_signature(name, &ir->actual_parameters, shader_list, + num_shaders); if (sig == NULL) { /* FINISHME: Log the full signature of unresolved function. */ @@ -82,6 +89,27 @@ public: return visit_stop; } + /* Find the prototype information in the linked shader. Generate any + * details that may be missing. + */ + ir_function *f = linked->symbols->get_function(name); + if (f == NULL) + f = new(linked) ir_function(name); + + ir_function_signature *linked_sig = + f->matching_signature(&callee->parameters); + if (linked_sig == NULL) { + linked_sig = new(linked) ir_function_signature(callee->return_type); + f->add_signature(linked_sig); + } + + /* At this point linked_sig and called may be the same. If ir is an + * ir_call from linked then linked_sig and callee will be + * ir_function_signatures that have no definitions (is_defined is false). + */ + assert(!linked_sig->is_defined); + assert(linked_sig->body.is_empty()); + /* Create an in-place clone of the function definition. This multistep * process introduces some complexity here, but it has some advantages. * The parameter list and the and function body are cloned separately. @@ -90,9 +118,9 @@ public: * * The big advantage is that the ir_function_signature does not change. * This means that we don't have to process the rest of the IR tree to - * patch ir_call nodes. In addition, there is no way to remove or replace - * signature stored in a function. One could easily be added, but this - * avoids the need. + * patch ir_call nodes. In addition, there is no way to remove or + * replace signature stored in a function. One could easily be added, + * but this avoids the need. */ struct hash_table *ht = hash_table_ctor(0, hash_table_pointer_hash, hash_table_pointer_compare); @@ -105,17 +133,16 @@ public: formal_parameters.push_tail(copy); } - callee->replace_parameters(&formal_parameters); + linked_sig->replace_parameters(&formal_parameters); - assert(callee->body.is_empty()); foreach_list_const(node, &sig->body) { const ir_instruction *const original = (ir_instruction *) node; ir_instruction *copy = original->clone(ht); - callee->body.push_tail(copy); + linked_sig->body.push_tail(copy); } - callee->is_defined = true; + linked_sig->is_defined = true; /* FINISHME: Patch references inside the function to things outside the * FINISHME: function (i.e., function calls and global variables). @@ -143,6 +170,14 @@ private: /** Number of shaders available for linking. */ unsigned num_shaders; + /** + * Final linked shader + * + * This is used two ways. It is used to find global variables in the + * linked shader that are accessed by the function. It is also used to add + * global variables from the shader where the function originated. + */ + gl_shader *linked; }; @@ -175,7 +210,7 @@ bool link_function_calls(gl_shader_program *prog, gl_shader *main, gl_shader **shader_list, unsigned num_shaders) { - call_link_visitor v(prog, shader_list, num_shaders); + call_link_visitor v(prog, main, shader_list, num_shaders); v.run(main->ir); return v.success; -- 2.7.4