From 01da2dc3774085caf30260e34bc0aeb5a990628e Mon Sep 17 00:00:00 2001
From: cosmonaut <evan@moonside.games>
Date: Fri, 4 Jun 2021 00:41:30 -0700
Subject: [PATCH] add some memory sys calls

---
 generic.w     | 19 +++++++++++---
 src/codegen.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 78 insertions(+), 10 deletions(-)

diff --git a/generic.w b/generic.w
index c127e17..ba8d511 100644
--- a/generic.w
+++ b/generic.w
@@ -21,7 +21,12 @@ struct MemoryBlock<T>
 
     Get(index: uint): T
     {
-        return @bitcast<T>(AddressOf(index));
+        return @dereference<T>(AddressOf(index));
+    }
+
+    Set(index: uint, value: T): void
+    {
+        @memcpy(AddressOf(index), @addr(value), @sizeof<T>());
     }
 
     Free(): void
@@ -34,13 +39,19 @@ struct Program {
     static Main(): int {
         x: int = 4;
         y: int = Foo.Func(x);
-        block: MemoryBlock<uint>;
+        block: MemoryBlock<int>;
         block.capacity = y;
         block.start = @malloc(y * @sizeof<int>());
         z: MemoryAddress = block.AddressOf(2);
-        Console.PrintLine("%u", block.Get(0));
         Console.PrintLine("%p", block.start);
-        Console.PrintLine("%p", z);
+        block.Set(0, 5);
+        block.Set(1, 3);
+        block.Set(2, 9);
+        block.Set(3, 100);
+        Console.PrintLine("%i", block.Get(0));
+        Console.PrintLine("%i", block.Get(1));
+        Console.PrintLine("%i", block.Get(2));
+        Console.PrintLine("%i", block.Get(3));
         block.Free();
         return 0;
     }
diff --git a/src/codegen.c b/src/codegen.c
index 991098f..f9cbf7b 100644
--- a/src/codegen.c
+++ b/src/codegen.c
@@ -1474,6 +1474,39 @@ static LLVMValueRef CompileSystemCallExpression(
 
             return LLVMSizeOf(ResolveType(ConcretizeType(typeTag)));
         }
+        else if (
+            strcmp(
+                systemCallExpression->systemCall.identifier->identifier.name,
+                "addr") == 0)
+        {
+            return LLVMBuildPtrToInt(
+                builder,
+                FindVariablePointer(
+                    systemCallExpression->systemCall.argumentSequence
+                        ->functionArgumentSequence.sequence[0]
+                        ->identifier.name),
+                LLVMInt64Type(),
+                "addrResult");
+        }
+        else if (
+            strcmp(
+                systemCallExpression->systemCall.identifier->identifier.name,
+                "dereference") == 0)
+        {
+            TypeTag *typeTag = ConcretizeType(
+                systemCallExpression->systemCall.genericArguments
+                    ->genericArguments.arguments[0]
+                    ->type.typeNode->typeTag);
+
+            return LLVMBuildLoad(
+                builder,
+                LLVMBuildIntToPtr(
+                    builder,
+                    args[0],
+                    LLVMPointerType(ResolveType(typeTag), 0),
+                    "deref_ptr"),
+                "deref");
+        }
         else if (
             strcmp(
                 systemCallExpression->systemCall.identifier->identifier.name,
@@ -1484,12 +1517,7 @@ static LLVMValueRef CompileSystemCallExpression(
                     ->genericArguments.arguments[0]
                     ->type.typeNode->typeTag);
 
-            LLVMValueRef expression = CompileExpression(
-                structTypeDeclaration,
-                selfParam,
-                builder,
-                systemCallExpression->systemCall.argumentSequence
-                    ->functionArgumentSequence.sequence[0]);
+            LLVMValueRef expression = args[0];
 
             return LLVMBuildBitCast(
                 builder,
@@ -2301,6 +2329,35 @@ static void RegisterLibraryFunctions(
 
     AddSystemFunction("free", freeFunctionType, freeFunction);
 
+    LLVMTypeRef memcpyParams[3];
+    memcpyParams[0] = LLVMInt64Type();
+    memcpyParams[1] = LLVMInt64Type();
+    memcpyParams[2] = LLVMInt64Type();
+    LLVMTypeRef memcpyFunctionType =
+        LLVMFunctionType(LLVMVoidType(), memcpyParams, 3, 0);
+    LLVMValueRef memcpyFunction =
+        LLVMAddFunction(module, "memcopy", memcpyFunctionType);
+
+    LLVMBasicBlockRef memcpyEntry =
+        LLVMAppendBasicBlock(memcpyFunction, "entry");
+    LLVMPositionBuilderAtEnd(builder, memcpyEntry);
+    LLVMValueRef dest = LLVMBuildIntToPtr(
+        builder,
+        LLVMGetParam(memcpyFunction, 0),
+        LLVMPointerType(LLVMInt64Type(), 0),
+        "dest");
+    LLVMValueRef src = LLVMBuildIntToPtr(
+        builder,
+        LLVMGetParam(memcpyFunction, 1),
+        LLVMPointerType(LLVMInt64Type(), 0),
+        "src");
+
+    LLVMBuildMemCpy(builder, dest, 8, src, 8, LLVMGetParam(memcpyFunction, 2));
+
+    LLVMBuildRetVoid(builder);
+
+    AddSystemFunction("memcpy", memcpyFunctionType, memcpyFunction);
+
     LLVMDisposeBuilder(builder);
 }