From a7639a685ee8e5444565ab1f969a9c917752ac61 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Wed, 2 Oct 2024 02:01:33 +0900
Subject: [PATCH] [qfcc] Add field and array expression types

And implement enough AST processing to compile fstrianglest.vert

Plenty of code-gen issues, though.
---
 tools/qfcc/include/expr.h        | 16 ++++++++
 tools/qfcc/include/expr_names.h  |  2 +
 tools/qfcc/source/expr.c         | 32 +++++++++++++++
 tools/qfcc/source/expr_assign.c  |  4 ++
 tools/qfcc/source/expr_dag.c     | 14 +++++++
 tools/qfcc/source/expr_process.c | 68 +++++++++++++++++++++++++++++++-
 tools/qfcc/source/glsl-parse.y   | 12 +++---
 tools/qfcc/source/statements.c   |  5 +++
 8 files changed, 146 insertions(+), 7 deletions(-)

diff --git a/tools/qfcc/include/expr.h b/tools/qfcc/include/expr.h
index 0eeec880d..7032a5e79 100644
--- a/tools/qfcc/include/expr.h
+++ b/tools/qfcc/include/expr.h
@@ -333,6 +333,18 @@ typedef struct {
 	const expr_t *false_expr;
 } ex_cond_t;
 
+typedef struct {
+	const expr_t *object;
+	const expr_t *member;
+	const type_t *type;
+} ex_field_t;
+
+typedef struct {
+	const expr_t *base;
+	const expr_t *index;
+	const type_t *type;
+} ex_array_t;
+
 #define POINTER_VAL(p) (((p).def ? (p).def->offset : 0) + (p).val)
 
 typedef struct expr_s {
@@ -378,6 +390,8 @@ typedef struct expr_s {
 		ex_type_t typ;					///< type expression
 		ex_incop_t incop;				///< incop expression
 		ex_cond_t cond;					///< ?: conditional expression
+		ex_field_t field;				///< field reference expression
+		ex_array_t array;				///< array index expression
 	};
 } expr_t;
 
@@ -889,6 +903,8 @@ expr_t *new_with_expr (int mode, int reg, const expr_t *val);
 expr_t *new_incop_expr (int op, const expr_t *e, bool postop);
 expr_t *new_cond_expr (const expr_t *test, const expr_t *true_expr,
 					   const expr_t *false_expr);
+expr_t *new_field_expr (const expr_t *object, const expr_t *member);
+expr_t *new_array_expr (const expr_t *base, const expr_t *index);
 
 /**	Create an expression of the correct type that references the specified
 	parameter slot.
diff --git a/tools/qfcc/include/expr_names.h b/tools/qfcc/include/expr_names.h
index 23492aa00..9dd31f061 100644
--- a/tools/qfcc/include/expr_names.h
+++ b/tools/qfcc/include/expr_names.h
@@ -71,6 +71,8 @@ EX_EXPR(list)		///< non-invasive list of expressions (::ex_list_t)
 EX_EXPR(type)		///< type expression for generics
 EX_EXPR(incop)		///< pre or post increment/decrement (::ex_incop_t)
 EX_EXPR(cond)		///< ?: conditional expression (::ex_cond_t)
+EX_EXPR(field)		///< field reference expression (::ex_field_t)
+EX_EXPR(array)		///< array index ex_field_t (::ex_array_t)
 
 #undef EX_EXPR
 
diff --git a/tools/qfcc/source/expr.c b/tools/qfcc/source/expr.c
index a731bef02..1205f0ec7 100644
--- a/tools/qfcc/source/expr.c
+++ b/tools/qfcc/source/expr.c
@@ -212,6 +212,10 @@ get_type (const expr_t *e)
 			//FIXME true_expr and false_expr need to have the same type,
 			//unless one is nil
 			return get_type (e->cond.true_expr);
+		case ex_field:
+			return e->field.type;
+		case ex_array:
+			return e->array.type;
 		case ex_count:
 			internal_error (e, "invalid expression");
 	}
@@ -1949,6 +1953,11 @@ has_function_call (const expr_t *e)
 			return (has_function_call (e->cond.test)
 					|| has_function_call (e->cond.true_expr)
 					|| has_function_call (e->cond.false_expr));
+		case ex_field:
+			return has_function_call (e->field.object);
+		case ex_array:
+			return (has_function_call (e->array.base)
+					|| has_function_call (e->array.index));
 		case ex_count:
 			break;
 	}
@@ -2505,6 +2514,29 @@ new_cond_expr (const expr_t *test, const expr_t *true_expr,
 	return cond;
 }
 
+expr_t *
+new_field_expr (const expr_t *object, const expr_t *member)
+{
+	auto field = new_expr ();
+	field->type = ex_field;
+	field->field = (ex_field_t) {
+		.object = object,
+		.member = member,
+	};
+	return field;
+}
+
+expr_t *
+new_array_expr (const expr_t *base, const expr_t *index)
+{
+	auto array = new_expr ();
+	array->type = ex_array;
+	array->array = (ex_array_t) {
+		.base = base,
+		.index = index,
+	};
+	return array;
+}
 
 const expr_t *
 incop_expr (int op, const expr_t *e, int postop)
diff --git a/tools/qfcc/source/expr_assign.c b/tools/qfcc/source/expr_assign.c
index 9e96525dd..10ef9e422 100644
--- a/tools/qfcc/source/expr_assign.c
+++ b/tools/qfcc/source/expr_assign.c
@@ -136,6 +136,10 @@ is_lvalue (const expr_t *expr)
 		case ex_cond:
 			return (is_lvalue (expr->cond.true_expr)
 					&& is_lvalue (expr->cond.false_expr));
+		case ex_field:
+			return 1;
+		case ex_array:
+			return 1;
 		case ex_count:
 			internal_error (expr, "invalid expression");
 	}
diff --git a/tools/qfcc/source/expr_dag.c b/tools/qfcc/source/expr_dag.c
index b46b17583..e58e95567 100644
--- a/tools/qfcc/source/expr_dag.c
+++ b/tools/qfcc/source/expr_dag.c
@@ -189,6 +189,20 @@ edag_add_expr (const expr_t *expr)
 					return e;
 				}
 				break;
+			case ex_field:
+				if (e->field.type == expr->field.type
+					&& e->field.object == expr->field.object
+					&& e->field.member == expr->field.member) {
+					return e;
+				}
+				break;
+			case ex_array:
+				if (e->array.type == expr->array.type
+					&& e->array.base == expr->array.base
+					&& e->array.index == expr->array.index) {
+					return e;
+				}
+				break;
 		}
 	}
 	DARRAY_APPEND (&expr_dag, expr);
diff --git a/tools/qfcc/source/expr_process.c b/tools/qfcc/source/expr_process.c
index eb3e0b43d..62111d311 100644
--- a/tools/qfcc/source/expr_process.c
+++ b/tools/qfcc/source/expr_process.c
@@ -75,6 +75,28 @@ proc_symbol (const expr_t *expr)
 	return expr;
 }
 
+static void
+proc_do_list (ex_list_t *out, const ex_list_t *in)
+{
+	int count = list_count (in);
+	const expr_t *exprs[count + 1];
+	list_scatter (in, exprs);
+	for (int i = 0; i < count; i++) {
+		exprs[i] = expr_process (exprs[i]);
+	}
+	list_gather (out, exprs, count);
+}
+
+static const expr_t *
+proc_vector (const expr_t *expr)
+{
+	auto vec = new_expr ();
+	vec->type = ex_vector;
+	vec->vector.type = expr->vector.type;
+	proc_do_list (&vec->vector.list, &expr->vector.list);
+	return vec;
+}
+
 static const expr_t *
 proc_value (const expr_t *expr)
 {
@@ -92,15 +114,59 @@ proc_compound (const expr_t *expr)
 	return comp;
 }
 
+static const expr_t *
+proc_assign (const expr_t *expr)
+{
+	auto dst = expr_process (expr->assign.dst);
+	auto src = expr_process (expr->assign.src);
+	if (is_error (src)) {
+		return src;
+	}
+	if (is_error (src)) {
+		return src;
+	}
+	return assign_expr (dst, src);
+}
+
+static const expr_t *
+proc_branch (const expr_t *expr)
+{
+	if (expr->branch.type == pr_branch_call) {
+		auto args = new_list_expr (nullptr);
+		proc_do_list (&args->list, &expr->branch.args->list);
+		return function_expr (expr->branch.target, args);
+	} else {
+		auto branch = new_expr ();
+		branch->type = ex_branch;
+		branch->branch = expr->branch;
+		branch->branch.target = expr_process (expr->branch.target);
+		branch->branch.index = expr_process (expr->branch.index);
+		branch->branch.test = expr_process (expr->branch.test);
+		if (is_error (branch->branch.target)) {
+			return branch->branch.target;
+		}
+		if (is_error (branch->branch.index)) {
+			return branch->branch.index;
+		}
+		if (is_error (branch->branch.test)) {
+			return branch->branch.test;
+		}
+		return branch;
+	}
+}
+
 const expr_t *
 expr_process (const expr_t *expr)
 {
 	static process_f funcs[ex_count] = {
 		[ex_expr] = proc_expr,
 		[ex_uexpr] = proc_uexpr,
+		[ex_symbol] = proc_symbol,
+		[ex_vector] = proc_vector,
 		[ex_value] = proc_value,
 		[ex_compound] = proc_compound,
-		[ex_symbol] = proc_symbol,
+		[ex_assign] = proc_assign,
+		[ex_branch] = proc_branch,
 	};
 
 	if (expr->type >= ex_count) {
diff --git a/tools/qfcc/source/glsl-parse.y b/tools/qfcc/source/glsl-parse.y
index fedffde28..b57b4f9a1 100644
--- a/tools/qfcc/source/glsl-parse.y
+++ b/tools/qfcc/source/glsl-parse.y
@@ -323,15 +323,15 @@ postfix_expression
 	: primary_exprsssion
 	| postfix_expression '[' integer_expression ']'
 		{
-			$$ = array_expr ($1, $3);
+			$$ = new_array_expr ($1, $3);
 		}
 	| function_call
 	| postfix_expression '.' IDENTIFIER/*FIELD_SELECTION*/
 		{
 			auto sym = new_symbol_expr ($3);
-			$$ = field_expr ($1, sym);
+			$$ = new_field_expr ($1, sym);
 		}
-	| postfix_expression INCOP			{ $$ = incop_expr ($2, $1, 1); }
+	| postfix_expression INCOP			{ $$ = new_incop_expr ($2, $1, 1); }
 	;
 
 integer_expression
@@ -354,7 +354,7 @@ function_call_or_method
 			auto func = exprs[count - 1];
 			auto args = new_list_expr (nullptr);
 			list_gather (&args->list, exprs, count - 1);
-			$$ = function_expr (func, args);
+			$$ = call_expr (func, args, nullptr);
 		}
 	;
 
@@ -402,7 +402,7 @@ function_identifier
 
 unary_expression
 	: postfix_expression
-	| INCOP unary_expression			{ $$ = incop_expr ($1, $2, 0); }
+	| INCOP unary_expression			{ $$ = new_incop_expr ($1, $2, 0); }
 	| unary_operator unary_expression	{ $$ = new_unary_expr ($1, $2); }
 	;
 
@@ -1041,7 +1041,7 @@ statement
 
 simple_statement
 	: declaration_statement
-	| expression_statement
+	| expression_statement { $$ = expr_process ($1); }//FIXME shouldn't be here
 	| selection_statement
 	| switch_statement
 	| case_label
diff --git a/tools/qfcc/source/statements.c b/tools/qfcc/source/statements.c
index d8cfe2068..e6ffae7bc 100644
--- a/tools/qfcc/source/statements.c
+++ b/tools/qfcc/source/statements.c
@@ -2078,6 +2078,11 @@ expr_symbol (sblock_t *sblock, const expr_t *e, operand_t **op)
 			make_function (sym, 0, pr.symtab->space, sc_extern);
 		}
 		*op = def_operand (sym->metafunc->func->def, 0, e);
+	} else if (sym->sy_type == sy_convert) {
+		e = sym->convert.conv (sym, sym->convert.data);
+		return statement_subexpr (sblock, e, op);
+	} else if (sym->sy_type == sy_expr) {
+		return statement_subexpr (sblock, sym->expr, op);
 	} else {
 		internal_error (e, "unexpected symbol type: %s for %s",
 						symtype_str (sym->sy_type), sym->name);