Merge branch 'callr-fix3' into 'main'

Fix some problems with callr and calli.

See merge request wingo/lightening!19

lightening/aarch64.c

@@ -261,3 +261,9 @@ bless_function_pointer(void *ptr)
 {
   return ptr;
 }
+
+static jit_gpr_t
+get_callr_temp (jit_state_t * _jit)
+{
+  return _LR;
+}

lightening/arm.c

@@ -109,7 +109,7 @@ next_abi_arg(struct abi_arg_iterator *iter, jit_operand_t *arg)
     }
   }
   *arg = jit_operand_mem (abi, JIT_SP, iter->stack_size);
-  iter->stack_size += 4;
+  iter->stack_size += 4 + (abi == JIT_OPERAND_ABI_DOUBLE ? 4 : 0);
 }
 
 static void
@@ -137,3 +137,9 @@ bless_function_pointer(void *ptr)
   // Set low bit to mark as thumb mode.
   return (void*) (((uintptr_t)ptr) | 1);
 }
+
+static jit_gpr_t
+get_callr_temp (jit_state_t * _jit)
+{
+  return _LR;
+}

lightening/lightening.c

@@ -124,6 +124,8 @@ static void reset_abi_arg_iterator(struct abi_arg_iterator *iter, size_t argc,
 static void next_abi_arg(struct abi_arg_iterator *iter,
                          jit_operand_t *arg);
 
+static jit_gpr_t get_callr_temp (jit_state_t * _jit);
+
 jit_bool_t
 init_jit(void)
 {
@@ -1096,6 +1098,15 @@ jit_move_operands(jit_state_t *_jit, jit_operand_t *dst, jit_operand_t *src,
   enum move_status status[argc];
   for (size_t i = 0; i < argc; i++)
     status[i] = TO_MOVE;
+
+  // Mem-to-mem moves require a temp register but don't overwrite
+  // other argument registers.  Perform them first to free up the tmp
+  // for other uses.
+  for (size_t i = 0; i < argc; i++)
+    if ((status[i] == TO_MOVE)
+	&& (MOVE_KIND (src[i].kind, dst[i].kind) == MOVE_MEM_TO_MEM))
+      move_one(_jit, dst, src, argc, status, i);
+
   for (size_t i = 0; i < argc; i++)
     if (status[i] == TO_MOVE)
       move_one(_jit, dst, src, argc, status, i);
@@ -1236,11 +1247,23 @@ jit_leave_jit_abi(jit_state_t *_jit, size_t v, size_t vf, size_t frame_size)
 
 // Precondition: stack is already aligned.
 static size_t
-prepare_call_args(jit_state_t *_jit, size_t argc, jit_operand_t args[])
+prepare_call_args(jit_state_t *_jit, size_t argc, jit_operand_t args[],
+		  jit_gpr_t *fun)
 {
-  jit_operand_t dst[argc];
+  size_t count = argc + (fun == NULL ? 0 : 1);
+  jit_operand_t src[count];
+  jit_operand_t dst[count];
+
+  memcpy (src, args, sizeof (jit_operand_t) * argc);
+  if (fun != NULL) {
+    jit_gpr_t fun_tmp = argc == 0 ? *fun : get_callr_temp (_jit);
+    src[argc] = jit_operand_gpr (JIT_OPERAND_ABI_POINTER, *fun);
+    dst[argc] = jit_operand_gpr (JIT_OPERAND_ABI_POINTER, fun_tmp);
+    *fun = fun_tmp;
+  }
+
   struct abi_arg_iterator iter;
-  
+
   // Compute shuffle destinations and space for spilled arguments.
   reset_abi_arg_iterator(&iter, argc, args);
   for (size_t i = 0; i < argc; i++)
@@ -1265,7 +1288,7 @@ prepare_call_args(jit_state_t *_jit, size_t argc, jit_operand_t args[])
     }
   }
 
-  jit_move_operands(_jit, dst, args, argc);
+  jit_move_operands(_jit, dst, src, count);
 
   return stack_size;
 }
@@ -1273,7 +1296,7 @@ prepare_call_args(jit_state_t *_jit, size_t argc, jit_operand_t args[])
 void
 jit_calli(jit_state_t *_jit, jit_pointer_t f, size_t argc, jit_operand_t args[])
 {
-  size_t stack_bytes = prepare_call_args(_jit, argc, args);
+  size_t stack_bytes = prepare_call_args(_jit, argc, args, NULL);
 
   calli(_jit, (jit_word_t)f);
 
@@ -1283,7 +1306,7 @@ jit_calli(jit_state_t *_jit, jit_pointer_t f, size_t argc, jit_operand_t args[])
 void
 jit_callr(jit_state_t *_jit, jit_gpr_t f, size_t argc, jit_operand_t args[])
 {
-  size_t stack_bytes = prepare_call_args(_jit, argc, args);
+  size_t stack_bytes = prepare_call_args(_jit, argc, args, &f);
 
   callr(_jit, jit_gpr_regno(f));
 

lightening/x86.c

@@ -405,3 +405,9 @@ bless_function_pointer(void *ptr)
 {
   return ptr;
 }
+
+static jit_gpr_t
+get_callr_temp (jit_state_t * _jit)
+{
+  return _RAX;
+}