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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"

 /* Prototype specifies unmangled function name and disables unused warning */

 static void

 invoke_copy_to_stack(uint64_t* d, uint32_t paramCount, nsXPTCVariant* s)

 __asm__("invoke_copy_to_stack") __attribute__((used));

 static void

 invoke_copy_to_stack(uint64_t* d, uint32_t paramCount, nsXPTCVariant* s)

 {

     const uint8_t NUM_ARG_REGS = 6-1;        // -1 for "this" pointer

     for(uint32_t i = 0; i < paramCount; i++, d++, s++)

     {

         if(s->IsPtrData())

         {

             *d = (uint64_t)s->ptr;

             continue;

         }

         switch(s->type)

         {

         case nsXPTType::T_I8     : *d = (uint64_t)s->val.i8;     break;

         case nsXPTType::T_I16    : *d = (uint64_t)s->val.i16;    break;

         case nsXPTType::T_I32    : *d = (uint64_t)s->val.i32;    break;

         case nsXPTType::T_I64    : *d = (uint64_t)s->val.i64;    break;

         case nsXPTType::T_U8     : *d = (uint64_t)s->val.u8;     break;

         case nsXPTType::T_U16    : *d = (uint64_t)s->val.u16;    break;

         case nsXPTType::T_U32    : *d = (uint64_t)s->val.u32;    break;

         case nsXPTType::T_U64    : *d = (uint64_t)s->val.u64;    break;

         case nsXPTType::T_FLOAT  :

             if(i < NUM_ARG_REGS)

             {

                 // convert floats to doubles if they are to be passed

                 // via registers so we can just deal with doubles later

                 union { uint64_t u64; double d; } t;

                 t.d = (double)s->val.f;

                 *d = t.u64;

             }

             else

                 // otherwise copy to stack normally

                 *d = (uint64_t)s->val.u32;

             break;

         case nsXPTType::T_DOUBLE : *d = (uint64_t)s->val.u64;    break;

         case nsXPTType::T_BOOL   : *d = (uint64_t)s->val.b;      break;

         case nsXPTType::T_CHAR   : *d = (uint64_t)s->val.c;      break;

         case nsXPTType::T_WCHAR  : *d = (uint64_t)s->val.wc;     break;

         default:

             // all the others are plain pointer types

             *d = (uint64_t)s->val.p;

             break;

         }

     }

 }

 /*

  * EXPORT_XPCOM_API(nsresult)

  * NS_InvokeByIndex(nsISupports* that, uint32_t methodIndex,

  *                  uint32_t paramCount, nsXPTCVariant* params)

  */

 __asm__(

     "#### NS_InvokeByIndex ####\n"

 ".text\n\t"

     ".align 5\n\t"

     ".globl NS_InvokeByIndex\n\t"

     ".ent NS_InvokeByIndex\n"

 "NS_InvokeByIndex:\n\t"

     ".frame $15,32,$26,0\n\t"

     ".mask 0x4008000,-32\n\t"

     "ldgp $29,0($27)\n"

 "$NS_InvokeByIndex..ng:\n\t"

     "subq $30,32,$30\n\t"

     "stq $26,0($30)\n\t"

     "stq $15,8($30)\n\t"

     "bis $30,$30,$15\n\t"

     ".prologue 1\n\t"

     /*

      * Allocate enough stack space to hold the greater of 6 or "paramCount"+1

      * parameters. (+1 for "this" pointer)  Room for at least 6 parameters

      * is required for storage of those passed via registers.

      */

     "bis $31,5,$2\n\t"      /* count = MAX(5, "paramCount") */

     "cmplt $2,$18,$1\n\t"

     "cmovne $1,$18,$2\n\t"

     "s8addq $2,16,$1\n\t"   /* room for count+1 params (8 bytes each) */

     "bic $1,15,$1\n\t"      /* stack space is rounded up to 0 % 16 */

     "subq $30,$1,$30\n\t"

     "stq $16,0($30)\n\t"    /* save "that" (as "this" pointer) */

     "stq $17,16($15)\n\t"   /* save "methodIndex" */

     "addq $30,8,$16\n\t"    /* pass stack pointer */

     "bis $18,$18,$17\n\t"   /* pass "paramCount" */

     "bis $19,$19,$18\n\t"   /* pass "params" */

     "bsr $26,$invoke_copy_to_stack..ng\n\t"     /* call invoke_copy_to_stack */

     /*

      * Copy the first 6 parameters to registers and remove from stack frame.

      * Both the integer and floating point registers are set for each parameter

      * except the first which is the "this" pointer.  (integer only)

      * The floating point registers are all set as doubles since the

      * invoke_copy_to_stack function should have converted the floats.

      */

     "ldq $16,0($30)\n\t"    /* integer registers */

     "ldq $17,8($30)\n\t"

     "ldq $18,16($30)\n\t"

     "ldq $19,24($30)\n\t"

     "ldq $20,32($30)\n\t"

     "ldq $21,40($30)\n\t"

     "ldt $f17,8($30)\n\t"   /* floating point registers */

     "ldt $f18,16($30)\n\t"

     "ldt $f19,24($30)\n\t"

     "ldt $f20,32($30)\n\t"

     "ldt $f21,40($30)\n\t"

     "addq $30,48,$30\n\t"   /* remove params from stack */

     /*

      * Call the virtual function with the constructed stack frame.

      */

     "bis $16,$16,$1\n\t"    /* load "this" */

     "ldq $2,16($15)\n\t"    /* load "methodIndex" */

     "ldq $1,0($1)\n\t"      /* load vtable */

     "s8addq $2,$31,$2\n\t"  /* vtable index = "methodIndex" * 8 */

     "addq $1,$2,$1\n\t"

     "ldq $27,0($1)\n\t"     /* load address of function */

     "jsr $26,($27),0\n\t"   /* call virtual function */

     "ldgp $29,0($26)\n\t"

     "bis $15,$15,$30\n\t"

     "ldq $26,0($30)\n\t"

     "ldq $15,8($30)\n\t"

     "addq $30,32,$30\n\t"

     "ret $31,($26),1\n\t"

     ".end NS_InvokeByIndex"

     );