38 lines
1.2 KiB
ArmAsm
38 lines
1.2 KiB
ArmAsm
//===-- save_restore_regs.S - Implement save/restore* ---------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include "../assembly.h"
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//
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// When compiling C++ functions that need to handle thrown exceptions the
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// compiler is required to save all registers and call __Unwind_SjLj_Register
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// in the function prolog. But when compiling for thumb1, there are
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// no instructions to access the floating point registers, so the
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// compiler needs to add a call to the helper function _save_vfp_d8_d15_regs
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// written in ARM to save the float registers. In the epilog, the compiler
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// must also add a call to __restore_vfp_d8_d15_regs to restore those registers.
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//
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.text
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.syntax unified
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//
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// Restore registers d8-d15 from stack
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//
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.align 2
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DEFINE_COMPILERRT_PRIVATE_FUNCTION(__restore_vfp_d8_d15_regs)
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vldmia sp!, {d8-d15} // pop registers d8-d15 off stack
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bx lr // return to prolog
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// tell linker it can break up file at label boundaries
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.subsections_via_symbols
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