1// Copyright 2006-2009 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28// CPU specific code for arm independent of OS goes here.
29#ifdef __arm__
30#include <sys/syscall.h>  // for cache flushing.
31#endif
32
33#include "v8.h"
34
35#if defined(V8_TARGET_ARCH_ARM)
36
37#include "cpu.h"
38#include "macro-assembler.h"
39#include "simulator.h"  // for cache flushing.
40
41namespace v8 {
42namespace internal {
43
44void CPU::SetUp() {
45  CpuFeatures::Probe();
46}
47
48
49bool CPU::SupportsCrankshaft() {
50  return CpuFeatures::IsSupported(VFP3);
51}
52
53
54void CPU::FlushICache(void* start, size_t size) {
55  // Nothing to do flushing no instructions.
56  if (size == 0) {
57    return;
58  }
59
60#if defined (USE_SIMULATOR)
61  // Not generating ARM instructions for C-code. This means that we are
62  // building an ARM emulator based target.  We should notify the simulator
63  // that the Icache was flushed.
64  // None of this code ends up in the snapshot so there are no issues
65  // around whether or not to generate the code when building snapshots.
66  Simulator::FlushICache(Isolate::Current()->simulator_i_cache(), start, size);
67#else
68  // Ideally, we would call
69  //   syscall(__ARM_NR_cacheflush, start,
70  //           reinterpret_cast<intptr_t>(start) + size, 0);
71  // however, syscall(int, ...) is not supported on all platforms, especially
72  // not when using EABI, so we call the __ARM_NR_cacheflush syscall directly.
73
74  register uint32_t beg asm("a1") = reinterpret_cast<uint32_t>(start);
75  register uint32_t end asm("a2") =
76      reinterpret_cast<uint32_t>(start) + size;
77  register uint32_t flg asm("a3") = 0;
78  #if defined (__arm__) && !defined(__thumb__)
79    // __arm__ may be defined in thumb mode.
80    register uint32_t scno asm("r7") = __ARM_NR_cacheflush;
81    asm volatile(
82        "svc 0x0"
83        : "=r" (beg)
84        : "0" (beg), "r" (end), "r" (flg), "r" (scno));
85  #else
86    // r7 is reserved by the EABI in thumb mode.
87    asm volatile(
88    "@   Enter ARM Mode  \n\t"
89        "adr r3, 1f      \n\t"
90        "bx  r3          \n\t"
91        ".ALIGN 4        \n\t"
92        ".ARM            \n"
93    "1:  push {r7}       \n\t"
94        "mov r7, %4      \n\t"
95        "svc 0x0         \n\t"
96        "pop {r7}        \n\t"
97    "@   Enter THUMB Mode\n\t"
98        "adr r3, 2f+1    \n\t"
99        "bx  r3          \n\t"
100        ".THUMB          \n"
101    "2:                  \n\t"
102        : "=r" (beg)
103        : "0" (beg), "r" (end), "r" (flg), "r" (__ARM_NR_cacheflush)
104        : "r3");
105  #endif
106#endif
107}
108
109
110void CPU::DebugBreak() {
111#if !defined (__arm__) || !defined(CAN_USE_ARMV5_INSTRUCTIONS)
112  UNIMPLEMENTED();  // when building ARM emulator target
113#else
114  asm volatile("bkpt 0");
115#endif
116}
117
118} }  // namespace v8::internal
119
120#endif  // V8_TARGET_ARCH_ARM
121