xref: /aosp_15_r20/art/tools/cpp-define-generator/asm_defines.cc (revision 795d594fd825385562da6b089ea9b2033f3abf5a)
1*795d594fSAndroid Build Coastguard Worker /*
2*795d594fSAndroid Build Coastguard Worker  * Copyright (C) 2018 The Android Open Source Project
3*795d594fSAndroid Build Coastguard Worker  *
4*795d594fSAndroid Build Coastguard Worker  * Licensed under the Apache License, Version 2.0 (the "License");
5*795d594fSAndroid Build Coastguard Worker  * you may not use this file except in compliance with the License.
6*795d594fSAndroid Build Coastguard Worker  * You may obtain a copy of the License at
7*795d594fSAndroid Build Coastguard Worker  *
8*795d594fSAndroid Build Coastguard Worker  *      http://www.apache.org/licenses/LICENSE-2.0
9*795d594fSAndroid Build Coastguard Worker  *
10*795d594fSAndroid Build Coastguard Worker  * Unless required by applicable law or agreed to in writing, software
11*795d594fSAndroid Build Coastguard Worker  * distributed under the License is distributed on an "AS IS" BASIS,
12*795d594fSAndroid Build Coastguard Worker  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13*795d594fSAndroid Build Coastguard Worker  * See the License for the specific language governing permissions and
14*795d594fSAndroid Build Coastguard Worker  * limitations under the License.
15*795d594fSAndroid Build Coastguard Worker  */
16*795d594fSAndroid Build Coastguard Worker 
17*795d594fSAndroid Build Coastguard Worker //
18*795d594fSAndroid Build Coastguard Worker // This file is used to generate #defines for use in assembly source code.
19*795d594fSAndroid Build Coastguard Worker //
20*795d594fSAndroid Build Coastguard Worker // The content of this file will be used to compile an object file
21*795d594fSAndroid Build Coastguard Worker // (generated as human readable assembly text file, not as binary).
22*795d594fSAndroid Build Coastguard Worker // This text file will then be post-processed by a python script to find
23*795d594fSAndroid Build Coastguard Worker // and extract the constants and generate the final asm_defines.h header.
24*795d594fSAndroid Build Coastguard Worker //
25*795d594fSAndroid Build Coastguard Worker 
26*795d594fSAndroid Build Coastguard Worker // We use "asm volatile" to generate text that will stand out in the
27*795d594fSAndroid Build Coastguard Worker // compiler generated intermediate assembly file (eg. ">>FOO 42 0<<").
28*795d594fSAndroid Build Coastguard Worker // We emit all values as 64-bit integers (which we will printed as text).
29*795d594fSAndroid Build Coastguard Worker // We also store a flag which specifies whether the constant is negative.
30*795d594fSAndroid Build Coastguard Worker // Note that "asm volatile" must be inside a method to please the compiler.
31*795d594fSAndroid Build Coastguard Worker #define ASM_DEFINE(NAME, EXPR) \
32*795d594fSAndroid Build Coastguard Worker void AsmDefineHelperFor_##NAME() { \
33*795d594fSAndroid Build Coastguard Worker   asm volatile("\n.ascii \">>" #NAME " %0 %1<<\"" \
34*795d594fSAndroid Build Coastguard Worker   :: "i" (static_cast<int64_t>(EXPR)), "i" ((EXPR) < 0 ? 1 : 0)); \
35*795d594fSAndroid Build Coastguard Worker }
36*795d594fSAndroid Build Coastguard Worker #include "asm_defines.def"
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