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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/. */

 // 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 PARAM_BUFFER_COUNT     16

 #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];

     nsXPTCMiniVariant* dispatchParams = nullptr;

     nsIInterfaceInfo* iface_info = nullptr;

     const nsXPTMethodInfo* info;

     uint32_t paramCount;

     uint32_t i;

     nsresult result = NS_ERROR_FAILURE;

     NS_ASSERTION(self,"no self");

     self->GetInterfaceInfo(&iface_info);

     NS_ASSERTION(iface_info,"no interface info");

     if (! iface_info)

         return NS_ERROR_UNEXPECTED;

     iface_info->GetMethodInfo(uint16_t(methodIndex), &info);

     NS_ASSERTION(info,"no method info");

     if (! info)

         return NS_ERROR_UNEXPECTED;

     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");

     if (! dispatchParams)

         return NS_ERROR_OUT_OF_MEMORY;

     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 = &dispatchParams[i];

         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;

 		if (gpr < GPR_COUNT)

 		    gpr += 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;

 		ap += 1;

 		if (gpr < GPR_COUNT)

 		    gpr += 1;

             }

             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()) {

             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;

         }

     }

     result = self->CallMethod((uint16_t) methodIndex, info, dispatchParams);

     NS_RELEASE(iface_info);

     if (dispatchParams != paramBuffer)

         delete [] dispatchParams;

     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 ;-).

 #define STUB_ENTRY(n)                                       \

 __asm__ (                                                   \

         ".section \".text\" \n\t"                           \

         ".align 2 \n\t"                                     \

 	".globl  Stub"#n"__14nsXPTCStubBase \n\t"           \

 	".type   Stub"#n"__14nsXPTCStubBase,@function \n\n" \

                                                             \

 "Stub"#n"__14nsXPTCStubBase: \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"