/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1999 Netscape Communications Corporation.  All Rights
 * Reserved.
 */

/* Implement shared vtbl methods. */

/* contributed by Glen Nakamura <glen.nakamura@usa.net> */

#include "xptcprivate.h"

/* Prototype specifies unmangled function name and disables unused warning */
static nsresult
PrepareAndDispatch(nsXPTCStubBase* self, uint32 methodIndex, PRUint64* args)
__asm__("PrepareAndDispatch") __attribute__((unused));

static nsresult
PrepareAndDispatch(nsXPTCStubBase* self, uint32 methodIndex, PRUint64* args)
{
    const PRUint8 PARAM_BUFFER_COUNT = 16;
    const PRUint8 NUM_ARG_REGS = 6-1;        // -1 for "this" pointer

    nsXPTCMiniVariant paramBuffer[PARAM_BUFFER_COUNT];
    nsXPTCMiniVariant* dispatchParams = NULL;
    nsIInterfaceInfo* iface_info = NULL;
    const nsXPTMethodInfo* info;
    PRUint8 paramCount;
    PRUint8 i;
    nsresult result = NS_ERROR_FAILURE;

    NS_ASSERTION(self,"no self");

    self->GetInterfaceInfo(&iface_info);
    NS_ASSERTION(iface_info,"no interface info");

    iface_info->GetMethodInfo(PRUint16(methodIndex), &info);
    NS_ASSERTION(info,"no interface info");

    paramCount = info->GetParamCount();

    // setup variant array pointer
    if(paramCount > PARAM_BUFFER_COUNT)
        dispatchParams = new nsXPTCMiniVariant[paramCount];
    else
        dispatchParams = paramBuffer;
    NS_ASSERTION(dispatchParams,"no place for params");

    // args[0] to args[NUM_ARG_REGS] hold floating point register values
    PRUint64* ap = args + NUM_ARG_REGS;
    for(i = 0; i < paramCount; i++, ap++)
    {
        const nsXPTParamInfo& param = info->GetParam(i);
        const nsXPTType& type = param.GetType();
        nsXPTCMiniVariant* dp = &dispatchParams[i];

        if(param.IsOut() || !type.IsArithmetic())
        {
            dp->val.p = (void*) *ap;
            continue;
        }
        // else
        switch(type)
        {
        case nsXPTType::T_I8     : dp->val.i8  = (PRInt8)    *ap;    break;
        case nsXPTType::T_I16    : dp->val.i16 = (PRInt16)   *ap;    break;
        case nsXPTType::T_I32    : dp->val.i32 = (PRInt32)   *ap;    break;
        case nsXPTType::T_I64    : dp->val.i64 = (PRInt64)   *ap;    break;
        case nsXPTType::T_U8     : dp->val.u8  = (PRUint8)   *ap;    break;
        case nsXPTType::T_U16    : dp->val.u16 = (PRUint16)  *ap;    break;
        case nsXPTType::T_U32    : dp->val.u32 = (PRUint32)  *ap;    break;
        case nsXPTType::T_U64    : dp->val.u64 = (PRUint64)  *ap;    break;
        case nsXPTType::T_FLOAT  :
            if(i < NUM_ARG_REGS)
            {
                // floats passed via registers are stored as doubles
                // in the first NUM_ARG_REGS entries in args
                dp->val.u64 = (PRUint64) args[i];
                dp->val.f = (float) dp->val.d;    // convert double to float
            }
            else
                dp->val.u32 = (PRUint32) *ap;
            break;
        case nsXPTType::T_DOUBLE :
            // doubles passed via registers are also stored
            // in the first NUM_ARG_REGS entries in args
            dp->val.u64 = (i < NUM_ARG_REGS) ? args[i] : *ap;
            break;
        case nsXPTType::T_BOOL   : dp->val.b   = (PRBool)    *ap;    break;
        case nsXPTType::T_CHAR   : dp->val.c   = (char)      *ap;    break;
        case nsXPTType::T_WCHAR  : dp->val.wc  = (PRUnichar) *ap;    break;
        default:
            NS_ASSERTION(0, "bad type");
            break;
        }
    }

    result = self->CallMethod((PRUint16)methodIndex, info, dispatchParams);

    NS_RELEASE(iface_info);

    if(dispatchParams != paramBuffer)
        delete [] dispatchParams;

    return result;
}

/*
 * SharedStub()
 *  Collects arguments and calls PrepareAndDispatch.  The "methodIndex" is
 *  passed to this function via $1 to preserve the argument registers.
 */
__asm__(
    "#### SharedStub ####\n"
".text\n\t"
    ".align 5\n\t"
    ".ent SharedStub\n"
"SharedStub:\n\t"
    ".frame $30,96,$26,0\n\t"
    ".mask 0x4000000,-96\n\t"
    "ldgp $29,0($27)\n"
"$SharedStub..ng:\n\t"
    "subq $30,96,$30\n\t"
    "stq $26,0($30)\n\t"
    ".prologue 1\n\t"

    /*
     * Store arguments passed via registers to the stack.
     * Floating point registers are stored as doubles and converted
     * to floats in PrepareAndDispatch if necessary.
     */
    "stt $f17,16($30)\n\t"   /* floating point registers */
    "stt $f18,24($30)\n\t"
    "stt $f19,32($30)\n\t"
    "stt $f20,40($30)\n\t"
    "stt $f21,48($30)\n\t"
    "stq $17,56($30)\n\t"    /* integer registers */
    "stq $18,64($30)\n\t"
    "stq $19,72($30)\n\t"
    "stq $20,80($30)\n\t"
    "stq $21,88($30)\n\t"

    /*
     * Call PrepareAndDispatch function.
     */
    "bis $1,$1,$17\n\t"      /* pass "methodIndex" */
    "addq $30,16,$18\n\t"    /* pass "args" */
    "bsr $26,$PrepareAndDispatch..ng\n\t"

    "ldq $26,0($30)\n\t"
    "addq $30,96,$30\n\t"
    "ret $31,($26),1\n\t"
    ".end SharedStub"
    );

/*
 * nsresult nsXPTCStubBase::Stub##n()
 *  Sets register $1 to "methodIndex" and jumps to SharedStub.
 */
#define STUB_ENTRY(n) \
__asm__( \
    "#### Stub"#n" ####\n" \
".text\n\t" \
    ".align 5\n\t" \
    ".globl Stub"#n"__14nsXPTCStubBase\n\t" \
    ".ent Stub"#n"__14nsXPTCStubBase\n" \
"Stub"#n"__14nsXPTCStubBase:\n\t" \
    ".frame $30,0,$26,0\n\t" \
    "ldgp $29,0($27)\n" \
"$Stub"#n"__14nsXPTCStubBase..ng:\n\t" \
    ".prologue 1\n\t" \
    "lda $1,"#n"\n\t" \
    "br $31,$SharedStub..ng\n\t" \
    ".end Stub"#n"__14nsXPTCStubBase" \
    );

#define SENTINEL_ENTRY(n) \
nsresult nsXPTCStubBase::Sentinel##n() \
{ \
    NS_ASSERTION(0,"nsXPTCStubBase::Sentinel called"); \
    return NS_ERROR_NOT_IMPLEMENTED; \
}

#include "xptcstubsdef.inc"

