Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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
// Implement shared vtbl methods.
#include "xptcprivate.h"
// The Linux/PPC ABI (aka PPC/SYSV ABI) passes the first 8 integral
// parameters and the first 8 floating point parameters in registers
// (r3-r10 and f1-f8), no stack space is allocated for these by the
// caller. The rest of the parameters are passed in the callers stack
// area. The stack pointer has to retain 16-byte alignment, longlongs
// and doubles are aligned on 8-byte boundaries.
#define GPR_COUNT 8
#define FPR_COUNT 8
// PrepareAndDispatch() is called by SharedStub() and calls the actual method.
//
// - 'args[]' contains the arguments passed on stack
// - 'gprData[]' contains the arguments passed in integer registers
// - 'fprData[]' contains the arguments passed in floating point registers
//
// The parameters are mapped into an array of type 'nsXPTCMiniVariant'
// and then the method gets called.
extern "C" nsresult ATTRIBUTE_USED
PrepareAndDispatch(nsXPTCStubBase* self,
uint32_t methodIndex,
uint32_t* args,
uint32_t *gprData,
double *fprData)
{
nsXPTCMiniVariant paramBuffer[PARAM_BUFFER_COUNT];
const nsXPTMethodInfo* info = nullptr;
uint32_t paramCount;
uint32_t i;
NS_ASSERTION(self,"no self");
self->mEntry->GetMethodInfo(uint16_t(methodIndex), &info);
NS_ASSERTION(info,"no method info");
if (! info)
return NS_ERROR_UNEXPECTED;
paramCount = info->GetParamCount();
const uint8_t indexOfJSContext = info->IndexOfJSContext();
uint32_t* ap = args;
uint32_t gpr = 1; // skip one GPR register
uint32_t fpr = 0;
uint32_t tempu32;
uint64_t tempu64;
for(i = 0; i < paramCount; i++) {
const nsXPTParamInfo& param = info->GetParam(i);
const nsXPTType& type = param.GetType();
nsXPTCMiniVariant* dp = ¶mBuffer[i];
if (i == indexOfJSContext) {
if (gpr < GPR_COUNT)
gpr++;
else
ap++;
}
if (!param.IsOut() && type == nsXPTType::T_DOUBLE) {
if (fpr < FPR_COUNT)
dp->val.d = fprData[fpr++];
else {
if ((uint32_t) ap & 4) ap++; // doubles are 8-byte aligned on stack
dp->val.d = *(double*) ap;
ap += 2;
}
continue;
}
else if (!param.IsOut() && type == nsXPTType::T_FLOAT) {
if (fpr < FPR_COUNT)
dp->val.f = (float) fprData[fpr++]; // in registers floats are passed as doubles
else
dp->val.f = *(float*) ap++;
continue;
}
else if (!param.IsOut() && (type == nsXPTType::T_I64
|| type == nsXPTType::T_U64)) {
if (gpr & 1) gpr++; // longlongs are aligned in odd/even register pairs, eg. r5/r6
if ((gpr + 1) < GPR_COUNT) {
tempu64 = *(uint64_t*) &gprData[gpr];
gpr += 2;
}
else {
if ((uint32_t) ap & 4) ap++; // longlongs are 8-byte aligned on stack
tempu64 = *(uint64_t*) ap;
ap += 2;
}
}
else {
if (gpr < GPR_COUNT)
tempu32 = gprData[gpr++];
else
tempu32 = *ap++;
}
if(param.IsOut() || !type.IsArithmetic()) {
if (type == nsXPTType::T_JSVAL)
dp->val.p = *((void**) tempu32);
else
dp->val.p = (void*) tempu32;
continue;
}
switch(type) {
case nsXPTType::T_I8: dp->val.i8 = (int8_t) tempu32; break;
case nsXPTType::T_I16: dp->val.i16 = (int16_t) tempu32; break;
case nsXPTType::T_I32: dp->val.i32 = (int32_t) tempu32; break;
case nsXPTType::T_I64: dp->val.i64 = (int64_t) tempu64; break;
case nsXPTType::T_U8: dp->val.u8 = (uint8_t) tempu32; break;
case nsXPTType::T_U16: dp->val.u16 = (uint16_t) tempu32; break;
case nsXPTType::T_U32: dp->val.u32 = (uint32_t) tempu32; break;
case nsXPTType::T_U64: dp->val.u64 = (uint64_t) tempu64; break;
case nsXPTType::T_BOOL: dp->val.b = (bool) tempu32; break;
case nsXPTType::T_CHAR: dp->val.c = (char) tempu32; break;
case nsXPTType::T_WCHAR: dp->val.wc = (wchar_t) tempu32; break;
default:
NS_ERROR("bad type");
break;
}
}
nsresult result = self->mOuter->CallMethod((uint16_t)methodIndex,
info,
paramBuffer);
return result;
}
// Load r11 with the constant 'n' and branch to SharedStub().
//
// XXX Yes, it's ugly that we're relying on gcc's name-mangling here;
// however, it's quick, dirty, and'll break when the ABI changes on
// us, which is what we want ;-).
// gcc-3 version
//
// As G++3 ABI contains the length of the functionname in the mangled
// name, it is difficult to get a generic assembler mechanism like
// in the G++ 2.95 case.
// Create names would be like:
// _ZN14nsXPTCStubBase5Stub1Ev
// _ZN14nsXPTCStubBase6Stub12Ev
// _ZN14nsXPTCStubBase7Stub123Ev
// _ZN14nsXPTCStubBase8Stub1234Ev
// etc.
// Use assembler directives to get the names right...
# define STUB_ENTRY(n) \
__asm__ ( \
".align 2 \n\t" \
".if "#n" < 10 \n\t" \
".globl _ZN14nsXPTCStubBase5Stub"#n"Ev \n\t" \
".type _ZN14nsXPTCStubBase5Stub"#n"Ev,@function \n\n" \
"_ZN14nsXPTCStubBase5Stub"#n"Ev: \n\t" \
\
".elseif "#n" < 100 \n\t" \
".globl _ZN14nsXPTCStubBase6Stub"#n"Ev \n\t" \
".type _ZN14nsXPTCStubBase6Stub"#n"Ev,@function \n\n" \
"_ZN14nsXPTCStubBase6Stub"#n"Ev: \n\t" \
\
".elseif "#n" < 1000 \n\t" \
".globl _ZN14nsXPTCStubBase7Stub"#n"Ev \n\t" \
".type _ZN14nsXPTCStubBase7Stub"#n"Ev,@function \n\n" \
"_ZN14nsXPTCStubBase7Stub"#n"Ev: \n\t" \
\
".else \n\t" \
".err \"stub number "#n" >= 1000 not yet supported\"\n" \
".endif \n\t" \
\
"li 11,"#n" \n\t" \
"b SharedStub@local \n" \
);
#define SENTINEL_ENTRY(n) \
nsresult nsXPTCStubBase::Sentinel##n() \
{ \
NS_ERROR("nsXPTCStubBase::Sentinel called"); \
return NS_ERROR_NOT_IMPLEMENTED; \
}
#include "xptcstubsdef.inc"