Commit 0541532ed6

Andrew Kelley <superjoe30@gmail.com>
2016-12-05 11:12:05
IR: implement generic function calls
1 parent 363606d
src/all_types.hpp
@@ -726,6 +726,19 @@ struct FnTypeParamInfo {
     TypeTableEntry *type;
 };
 
+struct GenericParamValue {
+    TypeTableEntry *type;
+    ConstExprValue *value;
+};
+
+struct GenericFnTypeId {
+    FnTableEntry *fn_entry;
+    GenericParamValue *params;
+    size_t param_count;
+};
+
+uint32_t generic_fn_type_id_hash(GenericFnTypeId *id);
+bool generic_fn_type_id_eql(GenericFnTypeId *a, GenericFnTypeId *b);
 
 struct FnTypeId {
     TypeTableEntry *return_type;
@@ -957,7 +970,6 @@ struct FnTableEntry {
     ScopeFnDef *fndef_scope; // parent should be the top level decls or container decls
     Scope *child_scope; // parent is scope for last parameter
     ScopeBlock *def_scope; // parent is child_scope
-    ImportTableEntry *import_entry;
     Buf symbol_name;
     TypeTableEntry *type_entry; // function type
     TypeTableEntry *implicit_return_type;
@@ -969,6 +981,7 @@ struct FnTableEntry {
     IrExecutable ir_executable;
     IrExecutable analyzed_executable;
     size_t prealloc_bbc;
+    AstNode **param_source_nodes;
 
     AstNode *fn_no_inline_set_node;
     AstNode *fn_export_set_node;
@@ -1050,6 +1063,7 @@ struct CodeGen {
     HashMap<Buf *, TypeTableEntry *, buf_hash, buf_eql_buf> primitive_type_table;
     HashMap<FnTypeId *, TypeTableEntry *, fn_type_id_hash, fn_type_id_eql> fn_type_table;
     HashMap<Buf *, ErrorTableEntry *, buf_hash, buf_eql_buf> error_table;
+    HashMap<GenericFnTypeId *, FnTableEntry *, generic_fn_type_id_hash, generic_fn_type_id_eql> generic_table;
 
     ZigList<ImportTableEntry *> import_queue;
     size_t import_queue_index;
@@ -1201,7 +1215,6 @@ struct VariableTableEntry {
     Scope *parent_scope;
     Scope *child_scope;
     LLVMValueRef param_value_ref;
-    bool force_depends_on_compile_var;
     bool shadowable;
     size_t mem_slot_index;
     size_t ref_count;
src/analyze.cpp
@@ -907,22 +907,25 @@ static TypeTableEntry *get_generic_fn_type(CodeGen *g, FnTypeId *fn_type_id) {
     return fn_type;
 }
 
-static TypeTableEntry *analyze_fn_type(CodeGen *g, TldFn *tld_fn) {
-    AstNode *proto_node = tld_fn->base.source_node;
+void init_fn_type_id(FnTypeId *fn_type_id, AstNode *proto_node) {
     assert(proto_node->type == NodeTypeFnProto);
     AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
 
-    FnTypeId fn_type_id = {0};
-    fn_type_id.is_extern = fn_proto->is_extern || (fn_proto->visib_mod == VisibModExport);
-    fn_type_id.is_naked = fn_proto->is_nakedcc;
-    fn_type_id.is_cold = fn_proto->is_coldcc;
-    fn_type_id.param_count = fn_proto->params.length;
-    fn_type_id.param_info = allocate_nonzero<FnTypeParamInfo>(fn_type_id.param_count);
-    fn_type_id.next_param_index = 0;
-    fn_type_id.is_var_args = fn_proto->is_var_args;
+    fn_type_id->is_extern = fn_proto->is_extern || (fn_proto->visib_mod == VisibModExport);
+    fn_type_id->is_naked = fn_proto->is_nakedcc;
+    fn_type_id->is_cold = fn_proto->is_coldcc;
+    fn_type_id->param_count = fn_proto->params.length;
+    fn_type_id->param_info = allocate_nonzero<FnTypeParamInfo>(fn_type_id->param_count);
+    fn_type_id->next_param_index = 0;
+    fn_type_id->is_var_args = fn_proto->is_var_args;
+}
 
-    FnTableEntry *fn_entry = tld_fn->fn_entry;
-    Scope *child_scope = fn_entry->fndef_scope ? &fn_entry->fndef_scope->base : tld_fn->base.parent_scope;
+static TypeTableEntry *analyze_fn_type(CodeGen *g, AstNode *proto_node, Scope *child_scope) {
+    assert(proto_node->type == NodeTypeFnProto);
+    AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
+
+    FnTypeId fn_type_id = {0};
+    init_fn_type_id(&fn_type_id, proto_node);
 
     for (; fn_type_id.next_param_index < fn_type_id.param_count; fn_type_id.next_param_index += 1) {
         AstNode *param_node = fn_proto->params.at(fn_type_id.next_param_index);
@@ -939,10 +942,6 @@ static TypeTableEntry *analyze_fn_type(CodeGen *g, TldFn *tld_fn) {
             return get_generic_fn_type(g, &fn_type_id);
         }
 
-        if (fn_entry && buf_len(param_node->data.param_decl.name) == 0) {
-            add_node_error(g, param_node, buf_sprintf("missing parameter name"));
-        }
-
         TypeTableEntry *type_entry = analyze_type_expr(g, child_scope, param_node->data.param_decl.type);
 
         switch (type_entry->id) {
@@ -1366,6 +1365,23 @@ static void get_fully_qualified_decl_name(Buf *buf, Tld *tld, uint8_t sep) {
     }
 }
 
+FnTableEntry *create_fn(CodeGen *g, AstNode *proto_node) {
+    assert(proto_node->type == NodeTypeFnProto);
+    AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
+
+    FnTableEntry *fn_table_entry = allocate<FnTableEntry>(1);
+    fn_table_entry->analyzed_executable.backward_branch_count = &fn_table_entry->prealloc_bbc;
+    fn_table_entry->analyzed_executable.backward_branch_quota = default_backward_branch_quota;
+    fn_table_entry->analyzed_executable.fn_entry = fn_table_entry;
+    fn_table_entry->ir_executable.fn_entry = fn_table_entry;
+    fn_table_entry->proto_node = proto_node;
+    fn_table_entry->fn_def_node = proto_node->data.fn_proto.fn_def_node;
+    fn_table_entry->fn_inline = fn_proto->is_inline ? FnInlineAlways : FnInlineAuto;
+    fn_table_entry->internal_linkage = (fn_proto->visib_mod != VisibModExport);
+
+    return fn_table_entry;
+}
+
 static void resolve_decl_fn(CodeGen *g, TldFn *tld_fn) {
     ImportTableEntry *import = tld_fn->base.import;
     AstNode *proto_node = tld_fn->base.source_node;
@@ -1381,17 +1397,7 @@ static void resolve_decl_fn(CodeGen *g, TldFn *tld_fn) {
         return;
     }
 
-    FnTableEntry *fn_table_entry = allocate<FnTableEntry>(1);
-    fn_table_entry->analyzed_executable.backward_branch_count = &fn_table_entry->prealloc_bbc;
-    fn_table_entry->analyzed_executable.backward_branch_quota = default_backward_branch_quota;
-    fn_table_entry->analyzed_executable.fn_entry = fn_table_entry;
-    fn_table_entry->ir_executable.fn_entry = fn_table_entry;
-    fn_table_entry->import_entry = import;
-    fn_table_entry->proto_node = proto_node;
-    fn_table_entry->fn_def_node = fn_def_node;
-    fn_table_entry->fn_inline = fn_proto->is_inline ? FnInlineAlways : FnInlineAuto;
-    fn_table_entry->internal_linkage = (fn_proto->visib_mod != VisibModExport);
-
+    FnTableEntry *fn_table_entry = create_fn(g, tld_fn->base.source_node);
     get_fully_qualified_decl_name(&fn_table_entry->symbol_name, &tld_fn->base, '_');
 
     tld_fn->fn_entry = fn_table_entry;
@@ -1399,9 +1405,18 @@ static void resolve_decl_fn(CodeGen *g, TldFn *tld_fn) {
     if (fn_table_entry->fn_def_node) {
         fn_table_entry->fndef_scope = create_fndef_scope(
             fn_table_entry->fn_def_node, tld_fn->base.parent_scope, fn_table_entry);
+
+        for (size_t i = 0; i < fn_proto->params.length; i += 1) {
+            AstNode *param_node = fn_proto->params.at(i);
+            assert(param_node->type == NodeTypeParamDecl);
+            if (buf_len(param_node->data.param_decl.name) == 0) {
+                add_node_error(g, param_node, buf_sprintf("missing parameter name"));
+            }
+        }
     }
 
-    fn_table_entry->type_entry = analyze_fn_type(g, tld_fn);
+    Scope *child_scope = fn_table_entry->fndef_scope ? &fn_table_entry->fndef_scope->base : tld_fn->base.parent_scope;
+    fn_table_entry->type_entry = analyze_fn_type(g, proto_node, child_scope);
 
     if (fn_table_entry->type_entry->id == TypeTableEntryIdInvalid) {
         tld_fn->base.resolution = TldResolutionInvalid;
@@ -2142,6 +2157,13 @@ bool type_is_codegen_pointer(TypeTableEntry *type) {
     return false;
 }
 
+AstNode *get_param_decl_node(FnTableEntry *fn_entry, size_t index) {
+    if (fn_entry->param_source_nodes)
+        return fn_entry->param_source_nodes[index];
+    else
+        return fn_entry->proto_node->data.fn_proto.params.at(index);
+}
+
 static void analyze_fn_body(CodeGen *g, FnTableEntry *fn_table_entry) {
     assert(fn_table_entry->anal_state != FnAnalStateProbing);
     if (fn_table_entry->anal_state != FnAnalStateReady)
@@ -2151,17 +2173,19 @@ static void analyze_fn_body(CodeGen *g, FnTableEntry *fn_table_entry) {
 
     AstNodeFnProto *fn_proto = &fn_table_entry->proto_node->data.fn_proto;
 
-    Scope *child_scope = &fn_table_entry->fndef_scope->base;
-    assert(child_scope);
+    assert(fn_table_entry->fndef_scope);
+    if (!fn_table_entry->child_scope)
+        fn_table_entry->child_scope = &fn_table_entry->fndef_scope->base;
 
     // define local variables for parameters
     TypeTableEntry *fn_type = fn_table_entry->type_entry;
     assert(!fn_type->data.fn.is_generic);
     FnTypeId *fn_type_id = &fn_type->data.fn.fn_type_id;
     for (size_t i = 0; i < fn_type_id->param_count; i += 1) {
-        AstNode *param_decl_node = fn_proto->params.at(i);
-        AstNodeParamDecl *param_decl = &param_decl_node->data.param_decl;
         FnTypeParamInfo *param_info = &fn_type_id->param_info[i];
+        AstNode *param_decl_node = get_param_decl_node(fn_table_entry, i);
+        AstNodeParamDecl *param_decl = &param_decl_node->data.param_decl;
+        
 
         TypeTableEntry *param_type = param_info->type;
         bool is_noalias = param_info->is_noalias;
@@ -2175,9 +2199,9 @@ static void analyze_fn_body(CodeGen *g, FnTableEntry *fn_table_entry) {
                 buf_sprintf("byvalue types not yet supported on extern function parameters"));
         }
 
-        VariableTableEntry *var = add_variable(g, param_decl_node, child_scope, param_decl->name, param_type, true, nullptr);
+        VariableTableEntry *var = add_variable(g, param_decl_node, fn_table_entry->child_scope, param_decl->name, param_type, true, nullptr);
         var->src_arg_index = i;
-        child_scope = var->child_scope;
+        fn_table_entry->child_scope = var->child_scope;
         fn_table_entry->variable_list.append(var);
 
         if (fn_type->data.fn.gen_param_info) {
@@ -2185,8 +2209,6 @@ static void analyze_fn_body(CodeGen *g, FnTableEntry *fn_table_entry) {
         }
     }
 
-    fn_table_entry->child_scope = child_scope;
-
     TypeTableEntry *expected_type = fn_type_id->return_type;
 
     if (fn_type_id->is_extern && handle_is_ptr(expected_type)) {
@@ -2622,6 +2644,40 @@ static uint32_t hash_const_val(TypeTableEntry *type, ConstExprValue *const_val)
     zig_unreachable();
 }
 
+uint32_t generic_fn_type_id_hash(GenericFnTypeId *id) {
+    uint32_t result = 0;
+    result += hash_ptr(id->fn_entry);
+    for (size_t i = 0; i < id->param_count; i += 1) {
+        GenericParamValue *generic_param = &id->params[i];
+        if (generic_param->value) {
+            result += hash_const_val(generic_param->type, generic_param->value);
+            result += hash_ptr(generic_param->type);
+        }
+    }
+    return result;
+}
+
+bool generic_fn_type_id_eql(GenericFnTypeId *a, GenericFnTypeId *b) {
+    assert(a->fn_entry);
+    if (a->fn_entry != b->fn_entry) return false;
+    assert(a->param_count == b->param_count);
+    for (size_t i = 0; i < a->param_count; i += 1) {
+        GenericParamValue *a_val = &a->params[i];
+        GenericParamValue *b_val = &b->params[i];
+        if (a_val->type != b_val->type) return false;
+        if (a_val->value && b_val->value) {
+            assert(a_val->value->special == ConstValSpecialStatic);
+            assert(b_val->value->special == ConstValSpecialStatic);
+            if (!const_values_equal(a_val->value, b_val->value, a_val->type)) {
+                return false;
+            }
+        } else {
+            assert(!a_val->value && !b_val->value);
+        }
+    }
+    return true;
+}
+
 bool type_has_bits(TypeTableEntry *type_entry) {
     assert(type_entry);
     assert(type_entry->id != TypeTableEntryIdInvalid);
src/analyze.hpp
@@ -70,6 +70,9 @@ void init_tld(Tld *tld, TldId id, Buf *name, VisibMod visib_mod, AstNode *source
 VariableTableEntry *add_variable(CodeGen *g, AstNode *source_node, Scope *parent_scope, Buf *name,
     TypeTableEntry *type_entry, bool is_const, ConstExprValue *init_value);
 TypeTableEntry *analyze_type_expr(CodeGen *g, Scope *scope, AstNode *node);
+FnTableEntry *create_fn(CodeGen *g, AstNode *proto_node);
+void init_fn_type_id(FnTypeId *fn_type_id, AstNode *proto_node);
+AstNode *get_param_decl_node(FnTableEntry *fn_entry, size_t index);
 
 Scope *create_block_scope(AstNode *node, Scope *parent);
 Scope *create_defer_scope(AstNode *node, Scope *parent);
src/ast_render.cpp
@@ -397,7 +397,7 @@ static void render_node_extra(AstRender *ar, AstNode *node, bool grouped) {
                     assert(param_decl->type == NodeTypeParamDecl);
                     if (buf_len(param_decl->data.param_decl.name) > 0) {
                         const char *noalias_str = param_decl->data.param_decl.is_noalias ? "noalias " : "";
-                        const char *inline_str = param_decl->data.param_decl.is_inline ? "inline  " : "";
+                        const char *inline_str = param_decl->data.param_decl.is_inline ? "inline " : "";
                         fprintf(ar->f, "%s%s", noalias_str, inline_str);
                         print_symbol(ar, param_decl->data.param_decl.name);
                         fprintf(ar->f, ": ");
src/codegen.cpp
@@ -60,6 +60,7 @@ CodeGen *codegen_create(Buf *root_source_dir, const ZigTarget *target) {
     g->primitive_type_table.init(32);
     g->fn_type_table.init(32);
     g->error_table.init(16);
+    g->generic_table.init(16);
     g->is_release_build = false;
     g->is_test_build = false;
     g->want_h_file = true;
@@ -2305,11 +2306,8 @@ static void do_code_gen(CodeGen *g) {
         if (should_skip_fn_codegen(g, fn_table_entry))
             continue;
 
-        AstNode *proto_node = fn_table_entry->proto_node;
-        assert(proto_node->type == NodeTypeFnProto);
-        AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
-
         TypeTableEntry *fn_type = fn_table_entry->type_entry;
+        FnTypeId *fn_type_id = &fn_type->data.fn.fn_type_id;
 
         LLVMValueRef fn_val = fn_llvm_value(g, fn_table_entry);
 
@@ -2327,22 +2325,20 @@ static void do_code_gen(CodeGen *g) {
 
 
         // set parameter attributes
-        for (size_t param_decl_i = 0; param_decl_i < fn_proto->params.length; param_decl_i += 1) {
-            AstNode *param_node = fn_proto->params.at(param_decl_i);
-            assert(param_node->type == NodeTypeParamDecl);
-
-            FnGenParamInfo *info = &fn_type->data.fn.gen_param_info[param_decl_i];
-            size_t gen_index = info->gen_index;
-            bool is_byval = info->is_byval;
+        for (size_t param_i = 0; param_i < fn_type_id->param_count; param_i += 1) {
+            FnGenParamInfo *gen_info = &fn_type->data.fn.gen_param_info[param_i];
+            size_t gen_index = gen_info->gen_index;
+            bool is_byval = gen_info->is_byval;
 
             if (gen_index == SIZE_MAX) {
                 continue;
             }
 
-            TypeTableEntry *param_type = info->type;
+            FnTypeParamInfo *param_info = &fn_type_id->param_info[param_i];
+
+            TypeTableEntry *param_type = gen_info->type;
             LLVMValueRef argument_val = LLVMGetParam(fn_val, gen_index);
-            bool param_is_noalias = param_node->data.param_decl.is_noalias;
-            if (param_is_noalias) {
+            if (param_info->is_noalias) {
                 LLVMAddAttribute(argument_val, LLVMNoAliasAttribute);
             }
             if ((param_type->id == TypeTableEntryIdPointer && param_type->data.pointer.is_const) || is_byval) {
@@ -2402,7 +2398,6 @@ static void do_code_gen(CodeGen *g) {
         if (should_skip_fn_codegen(g, fn_table_entry))
             continue;
 
-        ImportTableEntry *import = fn_table_entry->import_entry;
         LLVMValueRef fn = fn_llvm_value(g, fn_table_entry);
         g->cur_fn = fn_table_entry;
         g->cur_fn_val = fn;
@@ -2412,10 +2407,6 @@ static void do_code_gen(CodeGen *g) {
             g->cur_ret_ptr = nullptr;
         }
 
-        AstNode *proto_node = fn_table_entry->proto_node;
-        assert(proto_node->type == NodeTypeFnProto);
-        AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
-
         build_all_basic_blocks(g, fn_table_entry);
         clear_debug_source_node(g);
 
@@ -2444,6 +2435,8 @@ static void do_code_gen(CodeGen *g) {
             *slot = LLVMBuildAlloca(g->builder, instruction->type_entry->type_ref, "");
         }
 
+        ImportTableEntry *import = get_scope_import(&fn_table_entry->fndef_scope->base);
+
         // create debug variable declarations for variables and allocate all local variables
         for (size_t var_i = 0; var_i < fn_table_entry->variable_list.length; var_i += 1) {
             VariableTableEntry *var = fn_table_entry->variable_list.at(var_i);
@@ -2484,10 +2477,12 @@ static void do_code_gen(CodeGen *g) {
             }
         }
 
+        FnTypeId *fn_type_id = &fn_table_entry->type_entry->data.fn.fn_type_id;
+
         // create debug variable declarations for parameters
         // rely on the first variables in the variable_list being parameters.
         size_t next_var_i = 0;
-        for (size_t param_i = 0; param_i < fn_proto->params.length; param_i += 1) {
+        for (size_t param_i = 0; param_i < fn_type_id->param_count; param_i += 1) {
             FnGenParamInfo *info = &fn_table_entry->type_entry->data.fn.gen_param_info[param_i];
             if (info->gen_index == SIZE_MAX)
                 continue;
@@ -3392,14 +3387,12 @@ void codegen_generate_h_file(CodeGen *g) {
     buf_resize(&h_buf, 0);
     for (size_t fn_def_i = 0; fn_def_i < g->fn_defs.length; fn_def_i += 1) {
         FnTableEntry *fn_table_entry = g->fn_defs.at(fn_def_i);
-        AstNode *proto_node = fn_table_entry->proto_node;
-        assert(proto_node->type == NodeTypeFnProto);
-        AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
 
-        if (fn_proto->visib_mod != VisibModExport)
+        if (fn_table_entry->internal_linkage)
             continue;
 
         FnTypeId *fn_type_id = &fn_table_entry->type_entry->data.fn.fn_type_id;
+
         Buf return_type_c = BUF_INIT;
         get_c_type(g, fn_type_id->return_type, &return_type_c);
 
@@ -3412,7 +3405,7 @@ void codegen_generate_h_file(CodeGen *g) {
         if (fn_type_id->param_count > 0) {
             for (size_t param_i = 0; param_i < fn_type_id->param_count; param_i += 1) {
                 FnTypeParamInfo *param_info = &fn_type_id->param_info[param_i];
-                AstNode *param_decl_node = fn_proto->params.at(param_i);
+                AstNode *param_decl_node = get_param_decl_node(fn_table_entry, param_i);
                 Buf *param_name = param_decl_node->data.param_decl.name;
 
                 const char *comma_str = (param_i == 0) ? "" : ", ";
src/ir.cpp
@@ -2825,9 +2825,8 @@ IrInstruction *ir_gen_fn(CodeGen *codegen, FnTableEntry *fn_entry) {
     AstNode *body_node = fn_def_node->data.fn_def.body;
 
     assert(fn_entry->child_scope);
-    Scope *child_scope = fn_entry->child_scope;
 
-    return ir_gen(codegen, body_node, child_scope, ir_executable);
+    return ir_gen(codegen, body_node, fn_entry->child_scope, ir_executable);
 }
 
 static ErrorMsg *ir_add_error(IrAnalyze *ira, IrInstruction *source_instruction, Buf *msg) {
@@ -4220,9 +4219,9 @@ static TypeTableEntry *ir_analyze_instruction_decl_var(IrAnalyze *ira, IrInstruc
 }
 
 static bool ir_analyze_fn_call_inline_arg(IrAnalyze *ira, AstNode *fn_proto_node,
-    IrInstruction *arg, Scope **exec_scope, size_t *next_arg_index)
+    IrInstruction *arg, Scope **exec_scope, size_t *next_proto_i)
 {
-    AstNode *param_decl_node = fn_proto_node->data.fn_proto.params.at(*next_arg_index);
+    AstNode *param_decl_node = fn_proto_node->data.fn_proto.params.at(*next_proto_i);
     assert(param_decl_node->type == NodeTypeParamDecl);
     AstNode *param_type_node = param_decl_node->data.param_decl.type;
     TypeTableEntry *param_type = analyze_type_expr(ira->codegen, *exec_scope, param_type_node);
@@ -4241,14 +4240,66 @@ static bool ir_analyze_fn_call_inline_arg(IrAnalyze *ira, AstNode *fn_proto_node
     VariableTableEntry *var = add_variable(ira->codegen, param_decl_node,
         *exec_scope, param_name, param_type, true, first_arg_val);
     *exec_scope = var->child_scope;
-    *next_arg_index += 1;
+    *next_proto_i += 1;
 
     return true;
 }
 
+static bool ir_analyze_fn_call_generic_arg(IrAnalyze *ira, AstNode *fn_proto_node,
+    IrInstruction *arg, Scope **child_scope, size_t *next_proto_i,
+    GenericFnTypeId *generic_id, FnTypeId *fn_type_id, IrInstruction **casted_args,
+    FnTableEntry *impl_fn)
+{
+    AstNode *param_decl_node = fn_proto_node->data.fn_proto.params.at(*next_proto_i);
+    assert(param_decl_node->type == NodeTypeParamDecl);
+    AstNode *param_type_node = param_decl_node->data.param_decl.type;
+    TypeTableEntry *param_type = analyze_type_expr(ira->codegen, *child_scope, param_type_node);
+    if (param_type->id == TypeTableEntryIdInvalid)
+        return false;
+
+    bool is_var_type = (param_type->id == TypeTableEntryIdVar);
+    IrInstruction *casted_arg;
+    if (is_var_type) {
+        casted_arg = arg;
+    } else {
+        casted_arg = ir_get_casted_value(ira, arg, param_type);
+        if (casted_arg->type_entry->id == TypeTableEntryIdInvalid)
+            return false;
+    }
+
+    bool inline_arg = param_decl_node->data.param_decl.is_inline;
+    if (inline_arg || is_var_type) {
+        ConstExprValue *arg_val = ir_resolve_const(ira, casted_arg);
+        if (!arg_val)
+            return false;
+
+        Buf *param_name = param_decl_node->data.param_decl.name;
+        VariableTableEntry *var = add_variable(ira->codegen, param_decl_node,
+            *child_scope, param_name, param_type, true, arg_val);
+        *child_scope = var->child_scope;
+        // This generic function instance could be called with anything, so when this variable is read it
+        // needs to know that it depends on compile time variable data.
+        var->value->depends_on_compile_var = true;
+
+        GenericParamValue *generic_param = &generic_id->params[generic_id->param_count];
+        generic_param->type = casted_arg->type_entry;
+        generic_param->value = arg_val;
+        generic_id->param_count += 1;
+    } else {
+        casted_args[fn_type_id->param_count] = casted_arg;
+        FnTypeParamInfo *param_info = &fn_type_id->param_info[fn_type_id->param_count];
+        param_info->type = param_type;
+        param_info->is_noalias = param_decl_node->data.param_decl.is_noalias;
+        impl_fn->param_source_nodes[fn_type_id->param_count] = param_decl_node;
+        fn_type_id->param_count += 1;
+    }
+    *next_proto_i += 1;
+    return true;
+}
+
 static TypeTableEntry *ir_analyze_fn_call(IrAnalyze *ira, IrInstructionCall *call_instruction,
     FnTableEntry *fn_entry, TypeTableEntry *fn_type, IrInstruction *fn_ref,
-    IrInstruction *first_arg_ptr, bool is_inline)
+    IrInstruction *first_arg_ptr, bool inline_fn_call)
 {
     FnTypeId *fn_type_id = &fn_type->data.fn.fn_type_id;
     size_t first_arg_1_or_0 = first_arg_ptr ? 1 : 0;
@@ -4278,7 +4329,8 @@ static TypeTableEntry *ir_analyze_fn_call(IrAnalyze *ira, IrInstructionCall *cal
         return ira->codegen->builtin_types.entry_invalid;
     }
 
-    if (is_inline) {
+    if (inline_fn_call) {
+        // No special handling is needed for compile time evaluation of generic functions.
         if (!fn_entry) {
             ir_add_error(ira, fn_ref, buf_sprintf("unable to evaluate constant expression"));
             return ira->codegen->builtin_types.entry_invalid;
@@ -4290,13 +4342,13 @@ static TypeTableEntry *ir_analyze_fn_call(IrAnalyze *ira, IrInstructionCall *cal
         // Fork a scope of the function with known values for the parameters.
         Scope *exec_scope = &fn_entry->fndef_scope->base;
 
-        size_t next_arg_index = 0;
+        size_t next_proto_i = 0;
         if (first_arg_ptr) {
             IrInstruction *first_arg = ir_get_deref(ira, first_arg_ptr, first_arg_ptr);
             if (first_arg->type_entry->id == TypeTableEntryIdInvalid)
                 return ira->codegen->builtin_types.entry_invalid;
 
-            if (!ir_analyze_fn_call_inline_arg(ira, fn_proto_node, first_arg, &exec_scope, &next_arg_index))
+            if (!ir_analyze_fn_call_inline_arg(ira, fn_proto_node, first_arg, &exec_scope, &next_proto_i))
                 return ira->codegen->builtin_types.entry_invalid;
         }
 
@@ -4305,7 +4357,7 @@ static TypeTableEntry *ir_analyze_fn_call(IrAnalyze *ira, IrInstructionCall *cal
             if (old_arg->type_entry->id == TypeTableEntryIdInvalid)
                 return ira->codegen->builtin_types.entry_invalid;
 
-            if (!ir_analyze_fn_call_inline_arg(ira, fn_proto_node, old_arg, &exec_scope, &next_arg_index))
+            if (!ir_analyze_fn_call_inline_arg(ira, fn_proto_node, old_arg, &exec_scope, &next_proto_i))
                 return ira->codegen->builtin_types.entry_invalid;
         }
 
@@ -4327,9 +4379,89 @@ static TypeTableEntry *ir_analyze_fn_call(IrAnalyze *ira, IrInstructionCall *cal
         return ir_finish_anal(ira, return_type);
     }
 
+    if (fn_type->data.fn.is_generic) {
+        assert(fn_entry);
+
+        IrInstruction **casted_args = allocate<IrInstruction *>(call_param_count);
+
+        // Fork a scope of the function with known values for the parameters.
+        Scope *parent_scope = fn_entry->fndef_scope->base.parent;
+        FnTableEntry *impl_fn = create_fn(ira->codegen, fn_proto_node);
+        impl_fn->param_source_nodes = allocate<AstNode *>(call_param_count);
+        buf_init_from_buf(&impl_fn->symbol_name, &fn_entry->symbol_name);
+        impl_fn->fndef_scope = create_fndef_scope(impl_fn->fn_def_node, parent_scope, impl_fn);
+        impl_fn->child_scope = &impl_fn->fndef_scope->base;
+        FnTypeId fn_type_id = {0};
+        init_fn_type_id(&fn_type_id, fn_proto_node);
+        fn_type_id.param_count = 0;
+
+        // TODO maybe GenericFnTypeId can be replaced with using the child_scope directly
+        // as the key in generic_table
+        GenericFnTypeId *generic_id = allocate<GenericFnTypeId>(1);
+        generic_id->fn_entry = fn_entry;
+        generic_id->param_count = 0;
+        generic_id->params = allocate<GenericParamValue>(src_param_count);
+        size_t next_proto_i = 0;
+
+        if (first_arg_ptr) {
+            IrInstruction *first_arg = ir_get_deref(ira, first_arg_ptr, first_arg_ptr);
+            if (first_arg->type_entry->id == TypeTableEntryIdInvalid)
+                return ira->codegen->builtin_types.entry_invalid;
+
+            if (!ir_analyze_fn_call_generic_arg(ira, fn_proto_node, first_arg, &impl_fn->child_scope,
+                &next_proto_i, generic_id, &fn_type_id, casted_args, impl_fn))
+            {
+                return ira->codegen->builtin_types.entry_invalid;
+            }
+        }
+        for (size_t call_i = 0; call_i < call_instruction->arg_count; call_i += 1) {
+            IrInstruction *arg = call_instruction->args[call_i]->other;
+            if (arg->type_entry->id == TypeTableEntryIdInvalid)
+                return ira->codegen->builtin_types.entry_invalid;
+
+            if (!ir_analyze_fn_call_generic_arg(ira, fn_proto_node, arg, &impl_fn->child_scope,
+                &next_proto_i, generic_id, &fn_type_id, casted_args, impl_fn))
+            {
+                return ira->codegen->builtin_types.entry_invalid;
+            }
+        }
+
+        auto existing_entry = ira->codegen->generic_table.put_unique(generic_id, impl_fn);
+        if (existing_entry) {
+            // throw away all our work and use the existing function
+            impl_fn = existing_entry->value;
+        } else {
+            // finish instantiating the function
+            AstNode *return_type_node = fn_proto_node->data.fn_proto.return_type;
+            TypeTableEntry *return_type = analyze_type_expr(ira->codegen, impl_fn->child_scope, return_type_node);
+            if (return_type->id == TypeTableEntryIdInvalid)
+                return ira->codegen->builtin_types.entry_invalid;
+            fn_type_id.return_type = return_type;
+
+            impl_fn->type_entry = get_fn_type(ira->codegen, &fn_type_id);
+            if (impl_fn->type_entry->id == TypeTableEntryIdInvalid)
+                return ira->codegen->builtin_types.entry_invalid;
+
+            ira->codegen->fn_protos.append(impl_fn);
+            ira->codegen->fn_defs.append(impl_fn);
+        }
+
+        size_t impl_param_count = impl_fn->type_entry->data.fn.fn_type_id.param_count;
+        IrInstruction *new_call_instruction = ir_build_call_from(&ira->new_irb, &call_instruction->base,
+                impl_fn, nullptr, impl_param_count, casted_args);
+
+        TypeTableEntry *return_type = impl_fn->type_entry->data.fn.fn_type_id.return_type;
+        if (type_has_bits(return_type) && handle_is_ptr(return_type)) {
+            FnTableEntry *callsite_fn = exec_fn_entry(ira->new_irb.exec);
+            assert(callsite_fn);
+            callsite_fn->alloca_list.append(new_call_instruction);
+        }
+
+        return ir_finish_anal(ira, return_type);
+    }
+
     IrInstruction **casted_args = allocate<IrInstruction *>(call_param_count);
     size_t next_arg_index = 0;
-
     if (first_arg_ptr) {
         IrInstruction *first_arg = ir_get_deref(ira, first_arg_ptr, first_arg_ptr);
         if (first_arg->type_entry->id == TypeTableEntryIdInvalid)
test/self_hosted2.zig
@@ -111,6 +111,33 @@ fn testCompileTimeFib() {
     assert(fib_7 == 13);
 }
 
+fn max(inline T: type, a: T, b: T) -> T {
+   if (a > b) a else b
+}
+const the_max = max(u32, 1234, 5678);
+
+fn testCompileTimeGenericEval() {
+    assert(the_max == 5678);
+}
+
+fn gimmeTheBigOne(a: u32, b: u32) -> u32 {
+    max(u32, a, b)
+}
+
+fn shouldCallSameInstance(a: u32, b: u32) -> u32 {
+    max(u32, a, b)
+}
+
+fn sameButWithFloats(a: f64, b: f64) -> f64 {
+    max(f64, a, b)
+}
+
+fn testFnWithInlineArgs() {
+    assert(gimmeTheBigOne(1234, 5678) == 5678);
+    assert(shouldCallSameInstance(34, 12) == 34);
+    assert(sameButWithFloats(0.43, 0.49) == 0.49);
+}
+
 
 fn assert(ok: bool) {
     if (!ok)
@@ -129,6 +156,8 @@ fn runAllTests() {
     testStructStatic();
     testStaticFnEval();
     testCompileTimeFib();
+    testCompileTimeGenericEval();
+    testFnWithInlineArgs();
 }
 
 export nakedcc fn _start() -> unreachable {