1//===-- save_restore_regs.S - Implement save/restore* ---------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9 10#include "../assembly.h" 11 12// 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. 20// 21 22 .text 23 .syntax unified 24 25// 26// Save registers d8-d15 onto stack 27// 28DEFINE_COMPILERRT_PRIVATE_FUNCTION(__save_vfp_d8_d15_regs) 29 vstmdb sp!, {d8-d15} // push registers d8-d15 onto stack 30 bx lr // return to prolog 31 32 // tell linker it can break up file at label boundaries 33 .subsections_via_symbols 34 35