diff dyncallback/dyncall_thunk_arm32_arm.c @ 0:3e629dc19168

initial from svn dyncall-1745
author Daniel Adler
date Thu, 19 Mar 2015 22:24:28 +0100
parents
children fb416abb2059
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dyncallback/dyncall_thunk_arm32_arm.c	Thu Mar 19 22:24:28 2015 +0100
@@ -0,0 +1,46 @@
+/*
+
+ Package: dyncall
+ Library: dyncallback
+ File: dyncallback/dyncall_thunk_arm32_arm.c
+ Description: Thunk - Implementation for ARM32 (ARM mode)
+ License:
+
+   Copyright (c) 2007-2015 Daniel Adler <dadler@uni-goettingen.de>,
+                           Tassilo Philipp <tphilipp@potion-studios.com>
+
+   Permission to use, copy, modify, and distribute this software for any
+   purpose with or without fee is hereby granted, provided that the above
+   copyright notice and this permission notice appear in all copies.
+
+   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+   WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+   MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+   ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+*/
+
+
+#include "dyncall_thunk.h"
+
+void dcbInitThunk(DCThunk* p, void (*entry)())
+{
+  /*
+    # ARM32 (ARM mode) thunk code:
+    .code 32
+      sub %r12, %r15, #8
+      ldr %r15, [%r15, #-4]
+  */
+
+  /* This code loads 'entry+8' into r15. The -4 is needed, because r15 as  */
+  /* program counter points to the current instruction+8, but the pointer  */
+  /* to the code to execute follows the ldr instruction directly. Add 8 to */
+  /* entry for similar reasons. NOTE: Latter seems to be implicit with     */ 
+  /* latest update of arm-eabi tools.                                      */
+  p->code[0]  = 0xe24fc008UL;  /* sub %r12, %r15, #8 */
+  p->code[1]  = 0xe51ff004UL;  /* ldr %r15, [%r15, #-4] */
+  p->entry = entry/*+8*/;
+}