Urho3D/Source/ThirdParty/AngelScript/source/as_callfunc_xenon.cpp

738 lines
20 KiB
C++

/*
AngelCode Scripting Library
Copyright (c) 2003-2015 Andreas Jonsson
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any
damages arising from the use of this software.
Permission is granted to anyone to use this software for any
purpose, including commercial applications, and to alter it and
redistribute it freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you
must not claim that you wrote the original software. If you use
this software in a product, an acknowledgment in the product
documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and
must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source
distribution.
The original version of this library can be located at:
http://www.angelcode.com/angelscript/
Andreas Jonsson
andreas@angelcode.com
*/
//
// as_callfunc_xenon.cpp
//
// These functions handle the actual calling of system functions
//
// This version is Xenon specific
// Modified from as_callfunc_ppc.cpp by Laszlo Perneky February 2007
//
// Modified by Cyril Tissier March 2010:
// various fixes in 'float' args passing / function return
// properly handling 'double' type
// various fixes in asm ppcFunc
// fix for variable arguments
//
// Modified by Anthony Clark May 2015
// Fixed the issue where int64 and uint64 could not be passed nativly
// few minor fixes within asm ppcFunc to handle int64 and uint64
// XBox 360 calling convention
// ===========================
// I've yet to find an official document with the ABI for XBox 360,
// but I'll describe what I've gathered from the code and tests
// performed by the AngelScript community.
//
// Arguments are passed in the following registers:
// r3 - r10 : integer/pointer arguments (each register is 64bit)
// fr1 - fr13 : float/double arguments (each register is 64bit)
//
// Arguments that don't fit in the registers will be pushed on the stack.
//
// When a float or double is passed as argument, its value will be placed
// in the next available float register, but it will also reserve general
// purpose register.
//
// Example: void foo(float a, int b). a will be passed in fr1 and b in r4.
//
// For each argument passed to a function an 8byte slot is reserved on the
// stack, so that the function can offload the value there if needed. The
// first slot is at r1+20, the next at r1+28, etc.
//
// If the function is a class method, the this pointer is passed as hidden
// first argument. If the function returns an object in memory, the address
// for that memory is passed as hidden first argument.
//
// Return value are placed in the following registers:
// r3 : integer/pointer values
// fr1 : float/double values
//
// Rules for registers
// r1 : stack pointer
// r14-r31 : nonvolatile, i.e. their values must be preserved
// fr14-fr31 : nonvolatile, i.e. their values must be preserved
// r0, r2, r13 : dedicated. I'm not sure what it means, but it is probably best not to use them
//
// The stack pointer must always be aligned at 8 bytes.
//
// References:
// https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/852569B20050FF77852569970071B0D6/$file/eabi_app.pdf
//
// TODO: The code doesn't handle objects passed by value (unless they are max 4 bytes in size)
#include "as_config.h"
#ifndef AS_MAX_PORTABILITY
#if defined(AS_XENON)
#include "as_callfunc.h"
#include "as_scriptengine.h"
#include "as_texts.h"
#include "as_tokendef.h"
#include "as_context.h"
#include <stdio.h>
#include <stdlib.h>
#include <xtl.h>
BEGIN_AS_NAMESPACE
#define AS_PPC_MAX_ARGS 32
#define AS_PPC_THISCALL_REG 1
#define AS_PPC_RETURNINMEM_REG 1
#define AS_PPC_ENDOFARGS 1
// The array used to send values to the correct places.
// Contains a byte of argTypes to indicate the register type to load, or zero if end of arguments
enum argTypes
{
ppcENDARG = 0,
ppcINTARG = 1,
ppcFLOATARG = 2,
ppcDOUBLEARG = 3
};
// Loads all data into the correct places and calls the function.
// pArgs is the array of the argument values
// pArgTypes is an array containing a byte indicating the type (enum argTypes) for each argument.
// dwFunc is the address of the function that will be called
asQWORD __declspec( naked ) ppcFunc(const asQWORD* pArgs, asDWORD dwFunc, const asBYTE* pArgTypes)
{
__asm
{
_ppcFunc:
// Prologue
// Read and stack the link register (return address)
mflr r12
stw r12,-8(r1)
// Backup all non-volatile registers we use in this function
std r31,-10h(r1) // stack pointer for pushing arguments
std r27,-18h(r1) // dwFunc
std r26,-20h(r1) // pArgs
std r25,-28h(r1) // pArgTypes
std r24,-30h(r1) // current arg type
std r23,-38h(r1) // counter for used GPRs
std r22,-40h(r1) // counter for used float registers
// Setup the stack frame to make room for the backup of registers
// and the arguments that will be passed to the application function.
// 512 bytes is enough for about 50 arguments plus backup of 8
// TODO: Should perhaps make this dynamic based on number of arguments
stwu r1,-200h(r1)
//////////////////////////////////////////////////////////////////////////
// Initialize local variables
//////////////////////////////////////////////////////////////////////////
// r31 is our pointer into the stack where the arguments will be place
// The MSVC optimizer seems to rely on nobody copying the r1 register directly
// so we can't just do a simple 'addi r31, r1, 14h' as the optimizer may
// end up moving this instruction to before the update of r1 above.
// Instead we'll read the previous stack pointer from the stack, and then
// subtract to get the correct offset.
lwz r31, 0(r1)
subi r31, r31, 1ECh // prev r1 - 512 + 20 = curr r1 + 20
mr r26, r3 // pArgs
mr r27, r4 // dwFunc
mr r25, r5 // pArgTypes
// Counting of used/assigned GPR's
sub r23, r23, r23
// Counting of used/assigned Float Registers
sub r22, r22, r22
// Begin loading and stacking registers
subi r25, r25, 1
//////////////////////////////////////////////////////////////////////////
// Fetch the next argument
//////////////////////////////////////////////////////////////////////////
ppcNextArg:
// Increment rArgTypePtr
addi r25, r25, 1
// Get data type
lbz r24, 0(r25)
// r24 holds the data type
cmplwi cr6, r24, 0
beq cr6, ppcArgsEnd
cmplwi cr6, r24, 1
beq cr6, ppcArgIsInteger
cmplwi cr6, r24, 2
beq cr6, ppcArgIsFloat
cmplwi cr6, r24, 3
beq cr6, ppcArgIsDouble
//////////////////////////////////////////////////////////////////////////
// Load and stack integer arguments
//////////////////////////////////////////////////////////////////////////
ppcArgIsInteger:
// Get the arg from the stack
ld r12, 0(r26)
// r23 holds the integer arg count so far
cmplwi cr6, r23, 0
beq cr6, ppcLoadIntReg0
cmplwi cr6, r23, 1
beq cr6, ppcLoadIntReg1
cmplwi cr6, r23, 2
beq cr6, ppcLoadIntReg2
cmplwi cr6, r23, 3
beq cr6, ppcLoadIntReg3
cmplwi cr6, r23, 4
beq cr6, ppcLoadIntReg4
cmplwi cr6, r23, 5
beq cr6, ppcLoadIntReg5
cmplwi cr6, r23, 6
beq cr6, ppcLoadIntReg6
cmplwi cr6, r23, 7
beq cr6, ppcLoadIntReg7
// no more than 8 parameters
b ppcLoadIntRegUpd
ppcLoadIntReg0:
mr r3, r12
b ppcLoadIntRegUpd
ppcLoadIntReg1:
mr r4, r12
b ppcLoadIntRegUpd
ppcLoadIntReg2:
mr r5, r12
b ppcLoadIntRegUpd
ppcLoadIntReg3:
mr r6, r12
b ppcLoadIntRegUpd
ppcLoadIntReg4:
mr r7, r12
b ppcLoadIntRegUpd
ppcLoadIntReg5:
mr r8, r12
b ppcLoadIntRegUpd
ppcLoadIntReg6:
mr r9, r12
b ppcLoadIntRegUpd
ppcLoadIntReg7:
mr r10, r12
b ppcLoadIntRegUpd
ppcLoadIntRegUpd:
std r12, 0(r31) // push on the stack
addi r31, r31, 8 // inc stack by 1 reg
addi r23, r23, 1 // Increment used int register count
addi r26, r26, 8 // Increment pArgs
b ppcNextArg // Call next arg
//////////////////////////////////////////////////////////////////////////
// Load and stack float arguments
//////////////////////////////////////////////////////////////////////////
ppcArgIsFloat:
// Get the arg from the stack
lfs fr0, 0(r26)
// r22 holds the float arg count so far
cmplwi cr6, r22, 0
beq cr6, ppcLoadFloatReg0
cmplwi cr6, r22, 1
beq cr6, ppcLoadFloatReg1
cmplwi cr6, r22, 2
beq cr6, ppcLoadFloatReg2
cmplwi cr6, r22, 3
beq cr6, ppcLoadFloatReg3
cmplwi cr6, r22, 4
beq cr6, ppcLoadFloatReg4
cmplwi cr6, r22, 5
beq cr6, ppcLoadFloatReg5
cmplwi cr6, r22, 6
beq cr6, ppcLoadFloatReg6
cmplwi cr6, r22, 7
beq cr6, ppcLoadFloatReg7
cmplwi cr6, r22, 8
beq cr6, ppcLoadFloatReg8
cmplwi cr6, r22, 9
beq cr6, ppcLoadFloatReg9
cmplwi cr6, r22, 10
beq cr6, ppcLoadFloatReg10
cmplwi cr6, r22, 11
beq cr6, ppcLoadFloatReg11
cmplwi cr6, r22, 12
beq cr6, ppcLoadFloatReg12
// no more than 12 parameters
b ppcLoadFloatRegUpd
ppcLoadFloatReg0:
fmr fr1, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg1:
fmr fr2, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg2:
fmr fr3, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg3:
fmr fr4, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg4:
fmr fr5, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg5:
fmr fr6, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg6:
fmr fr7, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg7:
fmr fr8, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg8:
fmr fr9, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg9:
fmr fr10, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg10:
fmr fr11, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg11:
fmr fr12, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatReg12:
fmr fr13, fr0
b ppcLoadFloatRegUpd
ppcLoadFloatRegUpd:
stfs fr0, 0(r31) // push on the stack
addi r31, r31, 8 // inc stack by 1 reg
addi r22, r22, 1 // Increment used float register count
addi r23, r23, 1 // Increment used int register count - a float reg eats up a GPR
addi r26, r26, 4 // Increment pArgs
b ppcNextArg // Call next arg
//////////////////////////////////////////////////////////////////////////
// Load and stack double float arguments
//////////////////////////////////////////////////////////////////////////
ppcArgIsDouble:
// Get the arg from the stack
lfd fr0, 0(r26)
// r22 holds the float arg count so far
cmplwi cr6, r22, 0
beq cr6, ppcLoadDoubleReg0
cmplwi cr6, r22, 1
beq cr6, ppcLoadDoubleReg1
cmplwi cr6, r22, 2
beq cr6, ppcLoadDoubleReg2
cmplwi cr6, r22, 3
beq cr6, ppcLoadDoubleReg3
cmplwi cr6, r22, 4
beq cr6, ppcLoadDoubleReg4
cmplwi cr6, r22, 5
beq cr6, ppcLoadDoubleReg5
cmplwi cr6, r22, 6
beq cr6, ppcLoadDoubleReg6
cmplwi cr6, r22, 7
beq cr6, ppcLoadDoubleReg7
cmplwi cr6, r22, 8
beq cr6, ppcLoadDoubleReg8
cmplwi cr6, r22, 9
beq cr6, ppcLoadDoubleReg9
cmplwi cr6, r22, 10
beq cr6, ppcLoadDoubleReg10
cmplwi cr6, r22, 11
beq cr6, ppcLoadDoubleReg11
cmplwi cr6, r22, 12
beq cr6, ppcLoadDoubleReg12
// no more than 12 parameters
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg0:
fmr fr1, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg1:
fmr fr2, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg2:
fmr fr3, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg3:
fmr fr4, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg4:
fmr fr5, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg5:
fmr fr6, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg6:
fmr fr7, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg7:
fmr fr8, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg8:
fmr fr9, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg9:
fmr fr10, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg10:
fmr fr11, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg11:
fmr fr12, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleReg12:
fmr fr13, fr0
b ppcLoadDoubleRegUpd
ppcLoadDoubleRegUpd:
stfd fr0, 0(r31) // push on the stack
addi r31, r31, 8 // inc stack by 1 reg
addi r22, r22, 1 // Increment used float register count
addi r23, r23, 1 // Increment used int register count
addi r26, r26, 8 // Increment pArgs
b ppcNextArg
//////////////////////////////////////////////////////////////////////////
// Finished
//////////////////////////////////////////////////////////////////////////
ppcArgsEnd:
// Call the function
mtctr r27
bctrl
// Epilogue
// Restore callers stack
addi r1, r1, 200h
// restore all registers we used in this fct
ld r22,-40h(r1)
ld r23,-38h(r1)
ld r24,-30h(r1)
ld r25,-28h(r1)
ld r26,-20h(r1)
ld r27,-18h(r1)
ld r31,-10h(r1)
// Fetch return link to caller
lwz r12,-8(r1)
mtlr r12
blr
}
}
asDWORD GetReturnedFloat()
{
// This variable must be declared volatile so that the
// compiler optimizations do not remove its initialization
// with the fr1 register due to believing the fr1 register
// isn't initialized.
volatile asDWORD f;
__asm
{
stfs fr1, f
}
return f;
}
asQWORD GetReturnedDouble()
{
// This variable must be declared volatile so that the
// compiler optimizations do not remove its initialization
// with the fr1 register due to believing the fr1 register
// isn't initialized.
volatile asQWORD f;
__asm
{
stfd fr1, f
}
return f;
}
// returns true if the given parameter is a 'variable argument'
inline bool IsVariableArgument( asCDataType type )
{
return (type.GetTokenType() == ttQuestion) ? true : false;
}
asQWORD CallSystemFunctionNative(asCContext *context, asCScriptFunction *descr, void *obj, asDWORD *args, void *retPointer, asQWORD &/*retQW2*/, void */*secondObject*/)
{
// TODO: Xenon does not yet support THISCALL_OBJFIRST/LAST
asCScriptEngine *engine = context->m_engine;
asSSystemFunctionInterface *sysFunc = descr->sysFuncIntf;
int callConv = sysFunc->callConv;
asQWORD retQW = 0;
void *func = (void*)sysFunc->func;
asDWORD *vftable;
// Pack the arguments into an array that ppcFunc() can use to load each CPU register properly
asBYTE ppcArgsType[AS_PPC_MAX_ARGS + AS_PPC_RETURNINMEM_REG + AS_PPC_THISCALL_REG + AS_PPC_ENDOFARGS];
asQWORD ppcArgs[AS_PPC_MAX_ARGS + AS_PPC_RETURNINMEM_REG + AS_PPC_THISCALL_REG];
int argsCnt = 0;
// If the function returns an object in memory, we allocate the memory and put the ptr to the front (will go to r3)
if( sysFunc->hostReturnInMemory )
{
ppcArgs[argsCnt] = (asDWORD)retPointer;
ppcArgsType[argsCnt] = ppcINTARG;
argsCnt++;
}
// If we have an object and it's not objectlast, then we put it as the first arg
if ( obj &&
callConv != ICC_CDECL_OBJLAST &&
callConv != ICC_CDECL_OBJLAST_RETURNINMEM )
{
ppcArgs[argsCnt] = (asDWORD)obj;
ppcArgsType[argsCnt] = ppcINTARG;
argsCnt++;
}
// If the function takes any objects by value, they must be copied
// to the stack, shifting the other arguments as necessary. paramBuffer
// will then replace the args pointer that was received from the VM.
// TODO: Is this really how XBox 360 passes objects by value?
asDWORD paramBuffer[AS_PPC_MAX_ARGS];
if( sysFunc->takesObjByVal )
{
int paramSize = 0;
int spos = 0;
int dpos = 1;
for( asUINT n = 0; n < descr->parameterTypes.GetLength(); n++ )
{
// Parameter object by value
if( descr->parameterTypes[n].IsObject() &&
!descr->parameterTypes[n].IsObjectHandle() &&
!descr->parameterTypes[n].IsReference() )
{
#ifdef COMPLEX_OBJS_PASSED_BY_REF
if( descr->parameterTypes[n].GetTypeInfo()->flags & COMPLEX_MASK )
{
paramBuffer[dpos++] = args[spos++];
paramSize++;
}
else
#endif
{
// Copy the object's memory to the buffer
memcpy( &paramBuffer[dpos], *(void**)(args + spos), descr->parameterTypes[n].GetSizeInMemoryBytes() );
// Delete the original memory
engine->CallFree(*(char**)(args + spos));
spos++;
dpos += descr->parameterTypes[n].GetSizeInMemoryDWords();
paramSize += descr->parameterTypes[n].GetSizeInMemoryDWords();
}
}
else
{
// Copy the value directly
paramBuffer[dpos++] = args[spos++];
if( descr->parameterTypes[n].GetSizeOnStackDWords() > 1 )
paramBuffer[dpos++] = args[spos++];
paramSize += descr->parameterTypes[n].GetSizeOnStackDWords();
}
// If this was a variable argument parameter, then account for the implicit typeId
if( IsVariableArgument( descr->parameterTypes[n] ) )
{
// the TypeId is just a DWORD
paramBuffer[dpos++] = args[spos++];
++paramSize;
}
}
// Keep a free location at the beginning
args = &paramBuffer[1];
asASSERT( paramSize <= AS_PPC_MAX_ARGS );
}
const asUINT paramCount = (asUINT)descr->parameterTypes.GetLength();
asBYTE * pCurArgType = (asBYTE*)&ppcArgsType[argsCnt];
asBYTE * pCurFixedArgValue = (asBYTE*)&ppcArgs[argsCnt];
asBYTE * pCurStackArgValue = (asBYTE*)args;
for( asUINT n = 0; n < paramCount; n++ )
{
argsCnt++;
if (descr->parameterTypes[n].IsFloatType() && !descr->parameterTypes[n].IsReference())
{
*pCurArgType++ = ppcFLOATARG;
*((float*) pCurFixedArgValue) = *((float*) pCurStackArgValue);
pCurFixedArgValue += 4;
pCurStackArgValue += 4;
}
else if (descr->parameterTypes[n].IsDoubleType() && !descr->parameterTypes[n].IsReference())
{
*pCurArgType++ = ppcDOUBLEARG;
*((double*) pCurFixedArgValue) = *((double*) pCurStackArgValue);
pCurFixedArgValue += 8;
pCurStackArgValue += 8;
}
else
{
// TODO: The code also ignore the fact that large objects
// passed by value has been copied to the stack
// in the above loop.
*pCurArgType++ = ppcINTARG;
*((asQWORD*) pCurFixedArgValue) = *((asUINT*) pCurStackArgValue);
if( !descr->parameterTypes[n].IsReference() )
{
// If the arg is not 4 bytes which we coppied, lets do it again the right way
asUINT numBytes = descr->parameterTypes[n].GetSizeInMemoryBytes();
if( numBytes == 1 )
{
*((asQWORD*) pCurFixedArgValue) = *((asBYTE*) pCurStackArgValue);
}
else if( numBytes == 2 )
{
*((asQWORD*) pCurFixedArgValue) = *((asWORD*) pCurStackArgValue);
}
else if( numBytes == 8 )
{
*((asQWORD*) pCurFixedArgValue) = *((asQWORD*) pCurStackArgValue);
pCurStackArgValue += 4; // Increase our cur stack arg value by 4 bytes to = 8 total later
}
}
pCurFixedArgValue += 8;
pCurStackArgValue += 4;
// if it is a variable argument, account for the typeId
// implicitly add another parameter (AFTER the parameter above) for the typeId
if( IsVariableArgument(descr->parameterTypes[n]) )
{
argsCnt++;
*pCurArgType++ = ppcINTARG;
*((int*) pCurFixedArgValue) = *((int*) pCurStackArgValue);
pCurFixedArgValue += 4;
pCurStackArgValue += 4;
}
}
}
// Add the arg list end indicator
ppcArgsType[argsCnt] = ppcENDARG;
switch( callConv )
{
case ICC_CDECL:
case ICC_CDECL_RETURNINMEM:
case ICC_STDCALL:
case ICC_STDCALL_RETURNINMEM:
case ICC_THISCALL:
case ICC_THISCALL_RETURNINMEM:
case ICC_CDECL_OBJFIRST:
case ICC_CDECL_OBJFIRST_RETURNINMEM:
{
retQW = ppcFunc( ppcArgs, (asDWORD)func, ppcArgsType );
break;
}
case ICC_VIRTUAL_THISCALL:
case ICC_VIRTUAL_THISCALL_RETURNINMEM:
{
// Get virtual function table from the object pointer
vftable = *(asDWORD**)obj;
retQW = ppcFunc( ppcArgs, vftable[asDWORD(func)>>2], ppcArgsType );
break;
}
case ICC_CDECL_OBJLAST:
case ICC_CDECL_OBJLAST_RETURNINMEM:
{
// Add the object pointer as the last argument
ppcArgsType[argsCnt++] = ppcINTARG;
ppcArgsType[argsCnt] = ppcENDARG;
*((asQWORD*)pCurFixedArgValue) = (asPWORD)obj;
retQW = ppcFunc( ppcArgs, (asDWORD)func, ppcArgsType );
break;
}
default:
context->SetInternalException( TXT_INVALID_CALLING_CONVENTION );
}
// If the return is a float value we need to get the value from the FP register
if( sysFunc->hostReturnFloat )
{
if( sysFunc->hostReturnSize == 1 )
*(asDWORD*)&retQW = GetReturnedFloat();
else
retQW = GetReturnedDouble();
}
else if( sysFunc->hostReturnSize == 1 )
{
// Move the bits to the higher value to compensate for the adjustment that the caller does
retQW <<= 32;
}
return retQW;
}
END_AS_NAMESPACE
#endif // AS_XENON
#endif // AS_MAX_PORTABILITY