1 //===-- save_restore_regs.S - Implement save/restore* ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "../assembly.h"
13 // When compiling C++ functions that need to handle thrown exceptions the
14 // compiler is required to save all registers and call __Unwind_SjLj_Register
15 // in the function prolog. But when compiling for thumb1, there are
16 // no instructions to access the floating point registers, so the
17 // compiler needs to add a call to the helper function _save_vfp_d8_d15_regs
18 // written in ARM to save the float registers. In the epilog, the compiler
19 // must also add a call to __restore_vfp_d8_d15_regs to restore those registers.
26 // Save registers d8-d15 onto stack
29 DEFINE_COMPILERRT_PRIVATE_FUNCTION(__save_vfp_d8_d15_regs)
30 vstmdb sp!, {d8-d15} // push registers d8-d15 onto stack
31 bx lr // return to prolog
33 // tell linker it can break up file at label boundaries
34 .subsections_via_symbols