hphp/tools/make_native-func-caller.php

   1 <?hh
   2 /*
   3    +----------------------------------------------------------------------+
   4    | HipHop for PHP                                                       |
   5    +----------------------------------------------------------------------+
   6    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   7    +----------------------------------------------------------------------+
   8    | This source file is subject to version 3.01 of the PHP license,      |
   9    | that is bundled with this package in the file LICENSE, and is        |
  10    | available through the world-wide-web at the following url:           |
  11    | http://www.php.net/license/3_01.txt                                  |
  12    | If you did not receive a copy of the PHP license and are unable to   |
  13    | obtain it through the world-wide-web, please send a note to          |
  14    | license@php.net so we can mail you a copy immediately.               |
  15    +----------------------------------------------------------------------+
  16 */
  17
  18
  19 /**
  20  * Generate the ABI wrapper functions for HPHP::Native::NativeFuncCaller
  21  *
  22  * The NativeFuncCaller class relies on specifics of the amd64 and ARMv8 ABIs
  23  * to reshuffle the order of certain arguments and reduce the number of
  24  * possible combinations (by a lot).
  25  *
  26  * If you don't understand how NativeFuncCaller works, don't use this script.
  27  * If you do, then adjust NUM_GP_ARGS/NUM_SIMD_ARGS as needed and pipe the
  28  * output of this script to runtime/vm/native-func-caller.h
  29  *
  30  * I solemnly swear that I am up to no good.
  31  */
  32 const NUM_GP_ARGS = 32; // Must match kMaxBuiltinArgs
  33 const NUM_SIMD_ARGS = 8; // Must match CPU's ABI definition for SIMD usage
  34
  35 function go($name, $ret) {
  36   $callerArgs = 'NativeFunction f, int64_t* GP, int GP_count, '.
  37                 'double* SIMD, int SIMD_count';
  38
  39   fwrite(STDOUT, "{$ret} callFunc{$name}Impl({$callerArgs}) {\n");
  40   fwrite(STDOUT, "  switch (GP_count) {\n");
  41   $gpargs = vec[];
  42   for ($gp = 0; $gp <= NUM_GP_ARGS; ++$gp) {
  43     fwrite(STDOUT, "    case {$gp}:\n");
  44     fwrite(STDOUT, "      switch (SIMD_count) {\n");
  45     $simdargs = vec[];
  46     for ($simd = 0; $simd <= NUM_SIMD_ARGS; ++$simd) {
  47       $argsD = implode(',', array_merge($gpargs, $simdargs));
  48       $argsC = vec[];
  49       for ($i = 0; $i < $gp; ++$i) {
  50         $argsC[] = "GP[$i]";
  51       }
  52       for ($i = 0; $i < $simd; ++$i) {
  53         $argsC[] = "SIMD[$i]";
  54       }
  55       $argsC = implode(',', $argsC);
  56       fwrite(STDOUT, "        case {$simd}:\n");
  57       fwrite(STDOUT, "          return (({$ret} (*)({$argsD}))f)({$argsC});\n");
  58       $simdargs[] = 'double';
  59     }
  60     fwrite(STDOUT, "        default: not_reached();\n");
  61     fwrite(STDOUT, "      }\n");
  62     $gpargs[] = 'int64_t';
  63   }
  64   fwrite(STDOUT, "    default: not_reached();\n");
  65   fwrite(STDOUT, "  }\n");
  66   fwrite(STDOUT, "}\n\n");
  67 }
  68
  69 <<__EntryPoint>>
  70 function main() {
  71   fwrite(STDOUT, "// @"."generated by hphp/tools/make_native-func-caller.php\n\n");
  72
  73   fwrite(STDOUT, "static_assert(kMaxBuiltinArgs == " . NUM_GP_ARGS.
  74               ",\"Regenerate native-func-caller.h for updated ".
  75               "kMaxBuiltinArgs\");\n\n");
  76
  77   fwrite(STDOUT, "static_assert(kNumSIMDRegs == " . NUM_SIMD_ARGS.
  78               ",\"Regenerate native-func-caller.h for updated ".
  79               "kNumSIMDRegs\");\n\n");
  80
  81   go('Double', 'double');
  82   go('Int64', 'int64_t');
  83   go('TV', 'TypedValue');
  84   fwrite(STDOUT, "template<class IndirectRet>\n");
  85   go('Indirect', 'IndirectRet');
  86 }