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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/* Platform specific code to invoke XPCOM methods on native objects */
#include "xptcprivate.h"
#include "xptc_gcc_x86_unix.h"
extern "C" {
static void ATTRIBUTE_USED __attribute__ ((regparm(3)))
invoke_copy_to_stack(uint32_t paramCount, nsXPTCVariant* s, uint32_t* d)
{
for(uint32_t i = paramCount; i >0; i--, d++, s++)
{
if(s->IsIndirect())
{
*((void**)d) = &s->val;
continue;
}
switch(s->type)
{
case nsXPTType::T_I64 : *((int64_t*) d) = s->val.i64; d++; break;
case nsXPTType::T_U64 : *((uint64_t*)d) = s->val.u64; d++; break;
case nsXPTType::T_DOUBLE : *((double*) d) = s->val.d; d++; break;
default : *((void**)d) = s->val.p; break;
}
}
}
} // extern "C"
/*
EXPORT_XPCOM_API(nsresult)
NS_InvokeByIndex(nsISupports* that, uint32_t methodIndex,
uint32_t paramCount, nsXPTCVariant* params);
Each param takes at most two 4-byte words.
It doesn't matter if we push too many words, and calculating the exact
amount takes time.
that = ebp + 0x08
methodIndex = ebp + 0x0c
paramCount = ebp + 0x10
params = ebp + 0x14
*/
__asm__ (
".text\n\t"
/* alignment here seems unimportant here; this was 16, now it's 2 which
is what xptcstubs uses. */
".align 2\n\t"
".globl " SYMBOL_UNDERSCORE "NS_InvokeByIndex\n\t"
#ifndef XP_MACOSX
".type " SYMBOL_UNDERSCORE "NS_InvokeByIndex,@function\n"
#endif
SYMBOL_UNDERSCORE "NS_InvokeByIndex:\n\t"
"pushl %ebp\n\t"
"movl %esp, %ebp\n\t"
"movl 0x10(%ebp), %eax\n\t"
"leal 0(,%eax,8),%edx\n\t"
/* set up call frame for method. */
"subl %edx, %esp\n\t" /* make room for params. */
/* Align to maximum x86 data size: 128 bits == 16 bytes == XMM register size.
* This is to avoid protection faults where SSE+ alignment of stack pointer
* is assumed and required, e.g. by GCC4's -ftree-vectorize option.
*/
"andl $0xfffffff0, %esp\n\t" /* drop(?) stack ptr to 128-bit align */
/* $esp should be aligned to a 16-byte boundary here (note we include an
* additional 4 bytes in a later push instruction). This will ensure $ebp
* in the function called below is aligned to a 0x8 boundary. SSE instructions
* like movapd/movdqa expect memory operand to be aligned on a 16-byte
* boundary. The GCC compiler will generate the memory operand using $ebp
* with an 8-byte offset.
*/
"subl $0xc, %esp\n\t" /* lower again; push/call below will re-align */
"movl %esp, %ecx\n\t" /* ecx = d */
"movl 8(%ebp), %edx\n\t" /* edx = this */
"pushl %edx\n\t" /* push this. esp % 16 == 0 */
"movl 0x14(%ebp), %edx\n\t"
"call " SYMBOL_UNDERSCORE "invoke_copy_to_stack\n\t"
"movl 0x08(%ebp), %ecx\n\t" /* 'that' */
"movl (%ecx), %edx\n\t"
"movl 0x0c(%ebp), %eax\n\t" /* function index */
"leal (%edx,%eax,4), %edx\n\t"
"call *(%edx)\n\t"
"movl %ebp, %esp\n\t"
"popl %ebp\n\t"
"ret\n"
#ifndef XP_MACOSX
".size " SYMBOL_UNDERSCORE "NS_InvokeByIndex, . -" SYMBOL_UNDERSCORE "NS_InvokeByIndex\n\t"
#endif
);