diff options
Diffstat (limited to 'lib/arm/restore_vfp_d8_d15_regs.S')
| -rw-r--r-- | lib/arm/restore_vfp_d8_d15_regs.S | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/arm/restore_vfp_d8_d15_regs.S b/lib/arm/restore_vfp_d8_d15_regs.S new file mode 100644 index 000000000000..25404cd25076 --- /dev/null +++ b/lib/arm/restore_vfp_d8_d15_regs.S @@ -0,0 +1,37 @@ +//===-- save_restore_regs.S - Implement save/restore* ---------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#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 + +// +// Restore registers d8-d15 from stack +// + .align 2 +DEFINE_COMPILERRT_PRIVATE_FUNCTION(__restore_vfp_d8_d15_regs) + vldmia sp!, {d8-d15} // pop registers d8-d15 off stack + bx lr // return to prolog + + + + // tell linker it can break up file at label boundaries + .subsections_via_symbols + |