conditionally unwrapping while loops

2026-08-11 18:33:54 +02:00
parent ba6052eef3
commit fa53ca2219
8 changed files with 486 additions and 307 deletions
@@ -924,6 +924,101 @@ lower_expr :: proc(state: ^State, expr_id: hir.Expr_Id) -> ir.Instruction_Id {
 	return last
 }

+lower_conditional_unwrap_header :: proc(
+	state: ^State,
+	statement: hir.Stmt,
+	success_lbl, false_lbl: i64,
+) {
+	for unwrap in statement.unwraps {
+		optional := lower_expr(state, unwrap.expr)
+		present := append_instruction(state, ir.Instruction{
+			op=.Optional_Is_Some,
+			span=statement.span,
+			type=types.BOOL,
+			target=ir.INVALID_REF,
+			a=optional,
+			b=ir.INVALID_INSTRUCTION,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+		next_lbl := fresh_label(state)
+		append_instruction(state, ir.Instruction{
+			op=.Cond_Br,
+			span=statement.span,
+			type=types.VOID,
+			a=present,
+			integer=next_lbl,
+			target=ir.Ref(u32(false_lbl)),
+			b=ir.INVALID_INSTRUCTION,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+		append_instruction(state, ir.Instruction{
+			op=.Label,
+			span=statement.span,
+			type=types.VOID,
+			integer=next_lbl,
+			target=ir.INVALID_REF,
+			a=ir.INVALID_INSTRUCTION,
+			b=ir.INVALID_INSTRUCTION,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+		if unwrap.local != hir.INVALID_LOCAL && int(unwrap.local) < len(state.func_locals) {
+			local := state.func_locals[unwrap.local]
+			slot := append_instruction(state, ir.Instruction{
+				op=.Alloca,
+				span=statement.span,
+				type=local.type,
+				target=ir.local_ref(ir.Local_Id(unwrap.local)),
+				a=ir.INVALID_INSTRUCTION,
+				b=ir.INVALID_INSTRUCTION,
+				diagnostic=source.INVALID_DIAGNOSTIC,
+			})
+			state.local_slots[unwrap.local] = slot
+			inner := append_instruction(state, ir.Instruction{
+				op=.Optional_Value,
+				span=statement.span,
+				type=local.type,
+				target=ir.INVALID_REF,
+				a=optional,
+				b=ir.INVALID_INSTRUCTION,
+				diagnostic=source.INVALID_DIAGNOSTIC,
+			})
+			append_instruction(state, ir.Instruction{
+				op=.Store,
+				span=statement.span,
+				type=local.type,
+				target=ir.INVALID_REF,
+				a=slot,
+				b=inner,
+				diagnostic=source.INVALID_DIAGNOSTIC,
+			})
+		}
+	}
+	if statement.guard != hir.INVALID_EXPR {
+		guard := lower_expr(state, statement.guard)
+		append_instruction(state, ir.Instruction{
+			op=.Cond_Br,
+			span=statement.span,
+			type=types.VOID,
+			a=guard,
+			integer=success_lbl,
+			target=ir.Ref(u32(false_lbl)),
+			b=ir.INVALID_INSTRUCTION,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+	} else {
+		append_instruction(state, ir.Instruction{
+			op=.Br,
+			span=statement.span,
+			type=types.VOID,
+			integer=success_lbl,
+			target=ir.INVALID_REF,
+			a=ir.INVALID_INSTRUCTION,
+			b=ir.INVALID_INSTRUCTION,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+	}
+}
+
 lower_statements :: proc(state: ^State, statements: []hir.Stmt_Id) {
 	hir_module := state.hir_module
 	for statement_id in statements {
@@ -1136,97 +1231,7 @@ lower_statements :: proc(state: ^State, statements: []hir.Stmt_Id) {
 			false_target := else_lbl if has_else else merge_lbl

 			if len(statement.unwraps) > 0 {
-				// Evaluate each optional exactly once, entering the next operand only
-				// after the previous one is present. Capture storage is initialized in
-				// these success blocks so the optional guard can use every binding.
-				for unwrap in statement.unwraps {
-					optional := lower_expr(state, unwrap.expr)
-					present := append_instruction(state, ir.Instruction{
-						op=.Optional_Is_Some,
-						span=statement.span,
-						type=types.BOOL,
-						target=ir.INVALID_REF,
-						a=optional,
-						b=ir.INVALID_INSTRUCTION,
-						diagnostic=source.INVALID_DIAGNOSTIC,
-					})
-					success_lbl := fresh_label(state)
-					append_instruction(state, ir.Instruction{
-						op=.Cond_Br,
-						span=statement.span,
-						type=types.VOID,
-						a=present,
-						integer=success_lbl,
-						target=ir.Ref(u32(false_target)),
-						b=ir.INVALID_INSTRUCTION,
-						diagnostic=source.INVALID_DIAGNOSTIC,
-					})
-					append_instruction(state, ir.Instruction{
-						op=.Label,
-						span=statement.span,
-						type=types.VOID,
-						integer=success_lbl,
-						target=ir.INVALID_REF,
-						a=ir.INVALID_INSTRUCTION,
-						b=ir.INVALID_INSTRUCTION,
-						diagnostic=source.INVALID_DIAGNOSTIC,
-					})
-					if unwrap.local != hir.INVALID_LOCAL && int(unwrap.local) < len(state.func_locals) {
-						local := state.func_locals[unwrap.local]
-						slot := append_instruction(state, ir.Instruction{
-							op=.Alloca,
-							span=statement.span,
-							type=local.type,
-							target=ir.local_ref(ir.Local_Id(unwrap.local)),
-							a=ir.INVALID_INSTRUCTION,
-							b=ir.INVALID_INSTRUCTION,
-							diagnostic=source.INVALID_DIAGNOSTIC,
-						})
-						state.local_slots[unwrap.local] = slot
-						inner := append_instruction(state, ir.Instruction{
-							op=.Optional_Value,
-							span=statement.span,
-							type=local.type,
-							target=ir.INVALID_REF,
-							a=optional,
-							b=ir.INVALID_INSTRUCTION,
-							diagnostic=source.INVALID_DIAGNOSTIC,
-						})
-						append_instruction(state, ir.Instruction{
-							op=.Store,
-							span=statement.span,
-							type=local.type,
-							target=ir.INVALID_REF,
-							a=slot,
-							b=inner,
-							diagnostic=source.INVALID_DIAGNOSTIC,
-						})
-					}
-				}
-				if statement.guard != hir.INVALID_EXPR {
-					guard := lower_expr(state, statement.guard)
-					append_instruction(state, ir.Instruction{
-						op=.Cond_Br,
-						span=statement.span,
-						type=types.VOID,
-						a=guard,
-						integer=then_lbl,
-						target=ir.Ref(u32(false_target)),
-						b=ir.INVALID_INSTRUCTION,
-						diagnostic=source.INVALID_DIAGNOSTIC,
-					})
-				} else {
-					append_instruction(state, ir.Instruction{
-						op=.Br,
-						span=statement.span,
-						type=types.VOID,
-						integer=then_lbl,
-						target=ir.INVALID_REF,
-						a=ir.INVALID_INSTRUCTION,
-						b=ir.INVALID_INSTRUCTION,
-						diagnostic=source.INVALID_DIAGNOSTIC,
-					})
-				}
+				lower_conditional_unwrap_header(state, statement, then_lbl, false_target)
 			} else {
 				cond := lower_expr(state, statement.expr)
 				append_instruction(state, ir.Instruction{
@@ -1282,12 +1287,16 @@ lower_statements :: proc(state: ^State, statements: []hir.Stmt_Id) {
 				target=ir.INVALID_REF, a=ir.INVALID_INSTRUCTION, b=ir.INVALID_INSTRUCTION,
 				diagnostic=source.INVALID_DIAGNOSTIC,
 			})
-			condition := lower_expr(state, statement.expr)
-			append_instruction(state, ir.Instruction{
-				op=.Cond_Br, span=statement.span, type=types.VOID,
-				a=condition, integer=body_lbl, target=ir.Ref(u32(exit_lbl)),
-				b=ir.INVALID_INSTRUCTION, diagnostic=source.INVALID_DIAGNOSTIC,
-			})
+			if len(statement.unwraps) > 0 {
+				lower_conditional_unwrap_header(state, statement, body_lbl, exit_lbl)
+			} else {
+				condition := lower_expr(state, statement.expr)
+				append_instruction(state, ir.Instruction{
+					op=.Cond_Br, span=statement.span, type=types.VOID,
+					a=condition, integer=body_lbl, target=ir.Ref(u32(exit_lbl)),
+					b=ir.INVALID_INSTRUCTION, diagnostic=source.INVALID_DIAGNOSTIC,
+				})
+			}
 			append_instruction(state, ir.Instruction{
 				op=.Label, span=statement.span, type=types.VOID, integer=body_lbl,
 				target=ir.INVALID_REF, a=ir.INVALID_INSTRUCTION, b=ir.INVALID_INSTRUCTION,