From 324d2121b108f276fb6c27dbc884c186cd1cad06 Mon Sep 17 00:00:00 2001
From: Tyler Wilding <xtvaser@gmail.com>
Date: Fri, 28 Aug 2020 21:01:59 -0400
Subject: [PATCH] push

---
 game/kernel/asm_funcs.asm |  6 +++---
 game/kernel/kscheme.cpp   | 37 ++++++++++++++++++++++++++++++-------
 2 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/game/kernel/asm_funcs.asm b/game/kernel/asm_funcs.asm
index 0e506f23f0..e3e39a6034 100644
--- a/game/kernel/asm_funcs.asm
+++ b/game/kernel/asm_funcs.asm
@@ -90,8 +90,8 @@ _call_goal_asm:
   mov rsi, rdx ;; rsi is GOAL second argument, rdx is windows second argument
   mov rdx, r8  ;; rdx is GOAL third argument, r8 is windows third argument
   mov r13, r9  ;; r13 is GOAL fp, r9 is windows fourth argument
-  mov r14, [rsp + 144] ;; symbol table
-  mov r15, [rsp + 152] ;; offset
+  mov r15, [rsp + 144] ;; symbol table
+  mov r14, [rsp + 152] ;; offset
   
   call r13
   
@@ -109,4 +109,4 @@ _call_goal_asm:
   pop rbx
   pop rdx
   
-  ret
+  ret
\ No newline at end of file
diff --git a/game/kernel/kscheme.cpp b/game/kernel/kscheme.cpp
index 8e21544dac..d5f569dc8d 100644
--- a/game/kernel/kscheme.cpp
+++ b/game/kernel/kscheme.cpp
@@ -317,24 +317,47 @@ u64 make_string_from_c(const char* c_str) {
  * creates a function object on the global heap.
  *
  * The implementation is to create a simple trampoline function which jumps to the C function.
+ *
+ *
  */
 Ptr<Function> make_function_from_c(void* func) {
   // allocate a function object on the global heap
   auto mem = Ptr<u8>(
-      alloc_heap_object(s7.offset + FIX_SYM_GLOBAL_HEAP, *(s7 + FIX_SYM_FUNCTION_TYPE), 0x40));
+      alloc_heap_object(s7.offset + FIX_SYM_GLOBAL_HEAP, *(s7 + FIX_SYM_FUNCTION_TYPE), 0x80));
   auto f = (uint64_t)func;
   auto fp = (u8*)&f;
 
+  int i = 0;
   // we will put the function address in RAX with a movabs rax, imm8
-  mem.c()[0] = 0x48;
-  mem.c()[1] = 0xb8;
-  for (int i = 0; i < 8; i++) {
-    mem.c()[2 + i] = fp[i];
+  mem.c()[i++] = 0x48;
+  mem.c()[i++] = 0xb8;
+  for (int j = 0; j < 8; j++) {
+    mem.c()[i++] = fp[j];
+  }
+
+  /*
+   * push rdi
+   * push rsi
+   * push rdx
+   * push rcx
+   * pop r9
+   * pop r8
+   * pop rdx
+   * pop rcx
+   *
+   * sub rsp, 40
+   * call rax
+   * add rsp, 40
+   * ret
+   */
+  for (auto x : {0x57, 0x56, 0x52, 0x51, 0x41, 0x59, 0x41, 0x58, 0x5A, 0x59, 0x48,
+                 0x83, 0xEC, 0x28, 0xFF, 0xD0, 0x48, 0x83, 0xC4, 0x28, 0xC3}) {
+    mem.c()[i++] = x;
   }
 
   // jmp rax
-  mem.c()[10] = 0xff;
-  mem.c()[11] = 0xe0;
+  //  mem.c()[10] = 0xff;
+  //  mem.c()[11] = 0xe0;
 
   // the C function's ret will return to the caller of this trampoline.