From 9e13604bbed5ff1d33f97ecdd26a01d1a2fae8a0 Mon Sep 17 00:00:00 2001
From: LiXiaoQi <lxq877250099@mail.ustc.edu.cn>
Date: Fri, 28 Oct 2022 00:17:00 +0800
Subject: [PATCH] 88 points, wow hahaha!

---
 Reports/3-ir-gen/report.md       |  4 ++++
 src/cminusfc/cminusf_builder.cpp | 38 +++++++++++++++++++++++---------
 2 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/Reports/3-ir-gen/report.md b/Reports/3-ir-gen/report.md
index d0ca11b..efe38fd 100644
--- a/Reports/3-ir-gen/report.md
+++ b/Reports/3-ir-gen/report.md
@@ -110,6 +110,10 @@ PB20111654 李晓奇
     - 发现ifelse语句忘了无条件跳转了……
    
     - 返现布尔表达式必须使用i1类型，类型要求真的太严格了！！
+   
+    - 知道了为什么clang生成的中间代码，会把实参声明一遍再拷贝了。
+      
+      在我看来方便编译器代码的生成，因为重新声明，push给scope的值是指针类型而不是纯值，这在后边访问Var中有用。
 
 ## 实验设计
 
diff --git a/src/cminusfc/cminusf_builder.cpp b/src/cminusfc/cminusf_builder.cpp
index 1f87e97..71fbc33 100644
--- a/src/cminusfc/cminusf_builder.cpp
+++ b/src/cminusfc/cminusf_builder.cpp
@@ -262,18 +262,21 @@ void CminusfBuilder::visit(ASTFunDeclaration &node) {
 void CminusfBuilder::visit(ASTParam &node) {
     //!TODO: This function is empty now.
     // If the parameter is int|float, copy and store them
+    auto param_value = cur_value;
     switch (node.type) {
         case TYPE_INT: {
-            scope.push(node.id, cur_value);
+            cur_value = builder->create_alloca(INT32_T);
             break;
         }
         case TYPE_FLOAT: {
-            scope.push(node.id, cur_value);
+            cur_value = builder->create_alloca(FLOAT_T);
             break;
         }
         case TYPE_VOID:
-            break;
+            return;
     }
+    scope.push(node.id, cur_value);
+    builder->create_store(param_value, cur_value);
 }
 
 // Done?
@@ -314,17 +317,30 @@ void CminusfBuilder::visit(ASTSelectionStmt &node) {
     node.expression->accept(*this);
     auto cond = cur_value;
     cast_to_i1(cond);
-    auto TBB = BasicBlock::create(builder->get_module(), "", cur_fun);
-    auto FBB = BasicBlock::create(builder->get_module(), "", cur_fun);
-    builder->create_cond_br(cond, TBB, FBB);
-
-    builder->set_insert_point(TBB);
-    node.if_statement->accept(*this);
-    builder->create_br(FBB);
 
-    builder->set_insert_point(FBB);
+    auto ifBB = BasicBlock::create(builder->get_module(), "", cur_fun);
+    auto endBB = BasicBlock::create(builder->get_module(), "", cur_fun);
     if (node.else_statement) {
+        auto elseBB = BasicBlock::create(builder->get_module(), "", cur_fun);
+        builder->create_cond_br(cond, ifBB, elseBB);
+
+        builder->set_insert_point(ifBB);
+        node.if_statement->accept(*this);
+        builder->create_br(endBB);
+
+        builder->set_insert_point(elseBB);
         node.else_statement->accept(*this);
+        builder->create_br(endBB);
+
+        builder->set_insert_point(endBB);
+    } else {
+        builder->create_cond_br(cond, ifBB, endBB);
+
+        builder->set_insert_point(ifBB);
+        node.if_statement->accept(*this);
+        builder->create_br(endBB);
+
+        builder->set_insert_point(endBB);
     }
     scope.exit();
 }
-- 
GitLab