add __save_vfp_d8_d15_regs and __restore_vfp_d8_d15_regs for ARM

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@85531 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 45 insertions, 0 deletions

diff --git a/lib/arm/save_restore_d8_d15.S b/lib/arm/save_restore_d8_d15.S
new file mode 100644
index 000000000..3ff0b4133
--- /dev/null
+++ b/lib/arm/save_restore_d8_d15.S
@@ -0,0 +1,45 @@
+//===-- 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 
+
+//
+// Save registers d8-d15 onto stack
+//
+DEFINE_COMPILERRT_PRIVATE_FUNCTION(__save_vfp_d8_d15_regs)
+	vstmdb	sp!, {d8-d15}           // push registers d8-d15 onto stack
+	bx      lr                      // return to prolog
+
+
+
+//
+// Restore registers d8-d15 from stack
+//
+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
+