| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "asm_support_arm.S" |
| |
| .section .text |
| // This function is used to check for the CPU's support for the sdiv |
| // instruction at runtime. It will either return the value 1 or |
| // will cause an invalid instruction trap (SIGILL signal). The |
| // caller must arrange for the signal handler to set the r0 |
| // register to 0 and move the pc forward by 4 bytes (to skip |
| // the invalid instruction). |
| ENTRY artCheckForArmSdivInstruction |
| mov r1,#1 |
| // depending on the architecture, the assembler will not allow an |
| // sdiv instruction, so we will have to output the bytes directly. |
| |
| // sdiv r0,r1,r1 is two words: 0xfb91 0xf1f0. We need little endian. |
| .byte 0x91,0xfb,0xf1,0xf0 |
| |
| // if the divide worked, r0 will have the value #1 (result of sdiv). |
| // It will have 0 otherwise (set by the signal handler) |
| // the value is just returned from this function. |
| bx lr |
| END artCheckForArmSdivInstruction |
