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- //===-- save_restore_regs.S - Implement save/restore* ---------------------===//
- //
- // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
- // See https://llvm.org/LICENSE.txt for license information.
- // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
- //
- //===----------------------------------------------------------------------===//
- #include "../assembly.h"
- //
- // When compiling C++ functions that need to handle thrown exceptions the
- // compiler is required to save all registers and call __Unwind_SjLj_Register
- // in the function prolog. But when compiling for thumb1, there are
- // no instructions to access the floating point registers, so the
- // compiler needs to add a call to the helper function _save_vfp_d8_d15_regs
- // written in ARM to save the float registers. In the epilog, the compiler
- // must also add a call to __restore_vfp_d8_d15_regs to restore those registers.
- //
- .text
- .syntax unified
- //
- // Save registers d8-d15 onto stack
- //
- .p2align 2
- DEFINE_COMPILERRT_PRIVATE_FUNCTION(__save_vfp_d8_d15_regs)
- vstmdb sp!, {d8-d15} // push registers d8-d15 onto stack
- bx lr // return to prolog
- END_COMPILERRT_FUNCTION(__save_vfp_d8_d15_regs)
- NO_EXEC_STACK_DIRECTIVE
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