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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* Platform specific code to invoke XPCOM methods on native objects */
#include "xptcprivate.h"
static uint32_t
invoke_count_words(uint32_t paramCount, nsXPTCVariant* s)
{
uint32_t overflow = 0, gpr = 1 /*this*/, fpr = 0;
for(uint32_t i = 0; i < paramCount; i++, s++)
{
if(s->IsIndirect())
{
if (gpr < 5) gpr++; else overflow++;
continue;
}
switch(s->type)
{
case nsXPTType::T_I8 :
case nsXPTType::T_I16 :
case nsXPTType::T_I32 :
case nsXPTType::T_I64 :
if (gpr < 5) gpr++; else overflow++;
break;
case nsXPTType::T_U8 :
case nsXPTType::T_U16 :
case nsXPTType::T_U32 :
case nsXPTType::T_U64 :
if (gpr < 5) gpr++; else overflow++;
break;
case nsXPTType::T_FLOAT :
case nsXPTType::T_DOUBLE :
if (fpr < 4) fpr++; else overflow++;
break;
case nsXPTType::T_BOOL :
case nsXPTType::T_CHAR :
case nsXPTType::T_WCHAR :
if (gpr < 5) gpr++; else overflow++;
break;
default:
// all the others are plain pointer types
if (gpr < 5) gpr++; else overflow++;
break;
}
}
/* Round up number of overflow words to ensure stack
stays aligned to 8 bytes. */
return (overflow + 1) & ~1;
}
static void
invoke_copy_to_stack(uint32_t paramCount, nsXPTCVariant* s, uint64_t* d_ov, uint32_t overflow)
{
uint64_t *d_gpr = d_ov + overflow;
uint64_t *d_fpr = (uint64_t *)(d_gpr + 4);
uint32_t gpr = 1 /*this*/, fpr = 0;
for(uint32_t i = 0; i < paramCount; i++, s++)
{
if(s->IsIndirect())
{
if (gpr < 5)
*((void**)d_gpr) = (void *) &s->val, d_gpr++, gpr++;
else
*((void**)d_ov ) = (void *) &s->val, d_ov++;
continue;
}
switch(s->type)
{
case nsXPTType::T_I8 :
if (gpr < 5)
*((int64_t*) d_gpr) = s->val.i8, d_gpr++, gpr++;
else
*((int64_t*) d_ov ) = s->val.i8, d_ov++;
break;
case nsXPTType::T_I16 :
if (gpr < 5)
*((int64_t*) d_gpr) = s->val.i16, d_gpr++, gpr++;
else
*((int64_t*) d_ov ) = s->val.i16, d_ov++;
break;
case nsXPTType::T_I32 :
if (gpr < 5)
*((int64_t*) d_gpr) = s->val.i32, d_gpr++, gpr++;
else
*((int64_t*) d_ov ) = s->val.i32, d_ov++;
break;
case nsXPTType::T_I64 :
if (gpr < 5)
*((int64_t*) d_gpr) = s->val.i64, d_gpr++, gpr++;
else
*((int64_t*) d_ov ) = s->val.i64, d_ov++;
break;
case nsXPTType::T_U8 :
if (gpr < 5)
*((uint64_t*) d_gpr) = s->val.u8, d_gpr++, gpr++;
else
*((uint64_t*) d_ov ) = s->val.u8, d_ov++;
break;
case nsXPTType::T_U16 :
if (gpr < 5)
*((uint64_t*)d_gpr) = s->val.u16, d_gpr++, gpr++;
else
*((uint64_t*)d_ov ) = s->val.u16, d_ov++;
break;
case nsXPTType::T_U32 :
if (gpr < 5)
*((uint64_t*)d_gpr) = s->val.u32, d_gpr++, gpr++;
else
*((uint64_t*)d_ov ) = s->val.u32, d_ov++;
break;
case nsXPTType::T_U64 :
if (gpr < 5)
*((uint64_t*)d_gpr) = s->val.u64, d_gpr++, gpr++;
else
*((uint64_t*)d_ov ) = s->val.u64, d_ov++;
break;
case nsXPTType::T_FLOAT :
if (fpr < 4)
*((float*) d_fpr) = s->val.f, d_fpr++, fpr++;
else
*(((float*) d_ov )+1) = s->val.f, d_ov++;
break;
case nsXPTType::T_DOUBLE :
if (fpr < 4)
*((double*) d_fpr) = s->val.d, d_fpr++, fpr++;
else
*((double*) d_ov ) = s->val.d, d_ov++;
break;
case nsXPTType::T_BOOL :
if (gpr < 5)
*((uint64_t*)d_gpr) = s->val.b, d_gpr++, gpr++;
else
*((uint64_t*)d_ov ) = s->val.b, d_ov++;
break;
case nsXPTType::T_CHAR :
if (gpr < 5)
*((uint64_t*)d_gpr) = s->val.c, d_gpr++, gpr++;
else
*((uint64_t*)d_ov ) = s->val.c, d_ov++;
break;
case nsXPTType::T_WCHAR :
if (gpr < 5)
*((uint64_t*)d_gpr) = s->val.wc, d_gpr++, gpr++;
else
*((uint64_t*)d_ov ) = s->val.wc, d_ov++;
break;
default:
// all the others are plain pointer types
if (gpr < 5)
*((void**) d_gpr) = s->val.p, d_gpr++, gpr++;
else
*((void**) d_ov ) = s->val.p, d_ov++;
break;
}
}
}
typedef nsresult (*vtable_func)(nsISupports *, uint64_t, uint64_t, uint64_t, uint64_t, double, double, double, double);
// Avoid AddressSanitizer instrumentation for the next function because it
// depends on __builtin_alloca behavior and alignment that cannot be relied on
// once the function is compiled with a version of ASan that has dynamic-alloca
// instrumentation enabled.
MOZ_ASAN_IGNORE
EXPORT_XPCOM_API(nsresult)
NS_InvokeByIndex(nsISupports* that, uint32_t methodIndex,
uint32_t paramCount, nsXPTCVariant* params)
{
vtable_func *vtable = *reinterpret_cast<vtable_func **>(that);
vtable_func method = vtable[methodIndex];
uint64_t overflow = invoke_count_words (paramCount, params);
uint64_t *stack_space = reinterpret_cast<uint64_t *>(__builtin_alloca((overflow + 8 /* 4 64-bits gpr + 4 64-bits fpr */) * 8));
uint64_t result;
invoke_copy_to_stack(paramCount, params, stack_space, overflow);
uint64_t *d_gpr = stack_space + overflow;
double *d_fpr = reinterpret_cast<double *>(d_gpr + 4);
return method(that, d_gpr[0], d_gpr[1], d_gpr[2], d_gpr[3], d_fpr[0], d_fpr[1], d_fpr[2], d_fpr[3]);
}
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