From c7fad53ab2a6c99ba24a7b84401024cdb2b32c5b Mon Sep 17 00:00:00 2001
From: Yujia Qiao <rapiz3142@gmail.com>
Date: Wed, 3 Nov 2021 21:24:14 +0800
Subject: [PATCH] hack. see all array type in funct proto as ptrs

---
 llvm.cc    | 18 ++++++++++++++++--
 llvm.h     |  1 +
 parser.h   |  4 ++--
 type.h     |  1 +
 visitor.cc | 10 +++++++++-
 5 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/llvm.cc b/llvm.cc
index 5d3b889..9096ee4 100644
--- a/llvm.cc
+++ b/llvm.cc
@@ -8,6 +8,16 @@ llvm::Type* llvmWrapper::getChar() { return llvm::Type::getInt8Ty(*ctx); }
 llvm::Type* llvmWrapper::getDouble() { return llvm::Type::getDoubleTy(*ctx); }
 
 llvm::Type* llvmWrapper::getType(Type type) {
+  auto baseType = getBaseType(type);
+  if (type.isArray)
+    return llvm::ArrayType::get(baseType, type.arraySize);
+  else if (type.isPointer)
+    return baseType->getPointerTo();
+  else
+    return baseType;
+}
+
+llvm::Type* llvmWrapper::getBaseType(Type type) {
   switch (type.base) {
     case Type::Base::INT:
       return getInt();
@@ -61,7 +71,11 @@ llvm::Value* llvmWrapper::implictConvert(llvm::Value* v, llvm::Type* t) {
       abortMsg("can't implict convert double into int");
     else
       return builder->CreateIntCast(v, t, true, "toint");
-  } else
-    abortMsg("unimplemented implict convert");
+  } else if (t->isArrayTy()) {
+    return v;
+  } else if (t->isPointerTy()) {
+    return builder->CreateGEP(v, 0);
+  }
+  abortMsg("unimplemented implict convert");
   return nullptr;
 }
diff --git a/llvm.h b/llvm.h
index 2309eec..f162ac6 100644
--- a/llvm.h
+++ b/llvm.h
@@ -27,6 +27,7 @@ struct llvmWrapper {
   llvm::Type* getChar();
   llvm::Type* getDouble();
   llvm::Type* getType(Type t);
+  llvm::Type* getBaseType(Type t);
   llvm::Value* convertToTruthy(llvm::Value*);
   llvm::Value* implictConvert(llvm::Value*, llvm::Type*);
   llvm::AllocaInst* createEntryBlockAlloca(llvm::Function* fun,
diff --git a/parser.h b/parser.h
index b64e620..ae37f29 100644
--- a/parser.h
+++ b/parser.h
@@ -29,8 +29,8 @@ class Parser {
   BlockStmt* forStmt();      // FOR '(' VAR_DECL EXPRESSION; EXPRESSION ')'
   WhileStmt* whileStmt();    // WHILE '(' EXPRESSION ')' STMT
   ReturnStmt* returnStmt();  // RETURN EXPR;
-  TypedVar typedVar();       // (VAR | INT | DOUBLE | CHAR) ID
-  VarDecl* varDecl(Type type, Token id);  // TYPE ('['SIZE']')? IDENTIFIER
+  TypedVar typedVar();  // (VAR | INT | DOUBLE | CHAR) '*'? ID ('['SIZE']')?
+  VarDecl* varDecl(Type type, Token id);  // TYPEDVAR
                                           // (EQUAL EXPRESSION)? ;
   FunDecl* funDecl(Type type,
                    Token id);  // TYPEDVAR '(' ARGS? ')' BLOCK?
diff --git a/type.h b/type.h
index 41c7375..182f56a 100644
--- a/type.h
+++ b/type.h
@@ -7,6 +7,7 @@ struct Type {
   enum class Base { VOID, INT, DOUBLE, CHAR, ARRAY, BOOL, FUNCTION } base;
   int arraySize;
   bool isArray;
+  bool isPointer;
   bool operator==(const Type& rhs) const {
     return base == rhs.base && arraySize == rhs.arraySize &&
            isArray == rhs.isArray;
diff --git a/visitor.cc b/visitor.cc
index 593321e..06a9ed1 100644
--- a/visitor.cc
+++ b/visitor.cc
@@ -271,7 +271,11 @@ void CodeGenExprVisitor::visit(Call* expr) {
     auto protoArg = fun->getArg(i++);
     v.visit(a);
     auto val = v.getValue();
-    val = l.implictConvert(val, protoArg->getType());
+    if (protoArg->getType()->isPointerTy()) {
+      // FIXME: a hack. see all array type in function prototype as ptrs
+    } else {
+      val = l.implictConvert(val, protoArg->getType());
+    }
     args.push_back(val);
     if (!args.back()) {
       value = nullptr;
@@ -339,6 +343,10 @@ void CodeGenVisitor::visit(FunDecl* st) {
   std::vector<llvm::Type*> args;
   for (auto [type, token] : st->args) {
     auto t = l.getType(type);
+    if (t->isArrayTy()) {
+      // FIXME: hack, see all array type in funct proto as ptrs
+      t = t->getArrayElementType()->getPointerTo();
+    }
     args.push_back(t);
   }