refactor: 拆分 counter expression 计数分发

2026-10-25 11:11:11 +08:00 · 2026-06-23 17:58:19 +08:00
parent 0170354250
commit 8a6fac5ef7
11 changed files with 590 additions and 426 deletions
@@ -0,0 +1,64 @@
+use super::*;
+
+impl Compiler {
+    pub(in crate::counter) fn count_conditional_expression(&self, expr: &Expression, ctx: &mut CompileCtx) {
+        let Expression::ConditionalExpression(cond) = expr else {
+            return;
+        };
+        let id = ctx.next_label_id();
+        let else_label = Label::TernaryElse(id);
+        let end_label = Label::TernaryEnd(id);
+
+        self.count_expression(&cond.test, ctx);
+        ctx.projected_pc += 1; // JMP_IF_FALSE
+        self.count_expression(&cond.consequent, ctx);
+        ctx.alloc_reg(); // result register
+        ctx.projected_pc += 1; // LOAD_VAR result <- consequent
+        ctx.projected_pc += 1; // JMP to end
+        ctx.label_map.insert(else_label, ctx.projected_pc);
+        self.count_expression(&cond.alternate, ctx);
+        ctx.projected_pc += 1; // LOAD_VAR result <- alternate
+        ctx.label_map.insert(end_label, ctx.projected_pc);
+    }
+
+    pub(in crate::counter) fn count_sequence_expression(&self, expr: &Expression, ctx: &mut CompileCtx) {
+        let Expression::SequenceExpression(seq) = expr else {
+            return;
+        };
+        for e in &seq.expressions {
+            self.count_expression(e, ctx);
+        }
+    }
+
+    pub(in crate::counter) fn count_logical_expression(&self, expr: &Expression, ctx: &mut CompileCtx) {
+        let Expression::LogicalExpression(log) = expr else {
+            return;
+        };
+        self.count_expression(&log.left, ctx);
+
+        let is_simple = is_side_effect_free(&log.left) && is_side_effect_free(&log.right);
+
+        if is_simple {
+            self.count_expression(&log.right, ctx);
+            ctx.alloc_reg();
+            ctx.projected_pc += 1; // AND/OR
+        } else {
+            let id = ctx.next_label_id();
+            ctx.alloc_reg(); // dup register
+            ctx.projected_pc += 1; // LOAD_VAR (DUP)
+            ctx.projected_pc += 1; // JMP_IF_FALSE, JMP_IF_TRUE, or JMP_IF_NULLISH
+            if matches!(log.operator, LogicalOperator::Coalesce) {
+                ctx.projected_pc += 1; // JMP over RHS on non-nullish
+                ctx.label_map.insert(Label::TernaryElse(id), ctx.projected_pc);
+            }
+            self.count_expression(&log.right, ctx);
+            ctx.projected_pc += 1; // LOAD_VAR (overwrite)
+            let skip_label = match log.operator {
+                LogicalOperator::And => Label::TernaryEnd(id),
+                LogicalOperator::Or => Label::TernaryElse(id),
+                LogicalOperator::Coalesce => Label::TernaryEnd(id),
+            };
+            ctx.label_map.insert(skip_label, ctx.projected_pc);
+        }
+    }
+}