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-rw-r--r--ports/sysdeps/arm/arm-mcount.S108
1 files changed, 108 insertions, 0 deletions
diff --git a/ports/sysdeps/arm/arm-mcount.S b/ports/sysdeps/arm/arm-mcount.S
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+++ b/ports/sysdeps/arm/arm-mcount.S
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+/* Implementation of profiling support.  ARM EABI version.
+   Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* Don't call mcount when calling mcount...  */
+#undef PROF
+
+#include <sysdep.h>
+
+
+#ifdef __thumb2__
+	.thumb
+	.syntax unified
+#endif
+
+
+/* Use an assembly stub with a special ABI.  The calling lr has been
+   pushed to the stack (which will be misaligned).  We should preserve
+   all registers except ip and pop a word off the stack.
+
+   NOTE: This assumes mcount_internal does not clobber any non-core
+   (coprocessor) registers.  Currently this is true, but may require
+   additional attention in the future.
+
+   The calling sequence looks something like:
+func:
+   push {lr}
+   bl __gnu_mount_nc
+   <function body>
+*/
+
+ENTRY(__gnu_mcount_nc)
+	push {r0, r1, r2, r3, lr}
+	cfi_adjust_cfa_offset (20)
+	cfi_rel_offset (r0, 0)
+	cfi_rel_offset (r1, 4)
+	cfi_rel_offset (r2, 8)
+	cfi_rel_offset (r3, 12)
+	cfi_rel_offset (lr, 16)
+	bic r1, lr, #1
+	ldr r0, [sp, #20]
+	bl __mcount_internal
+	pop {r0, r1, r2, r3, ip, lr}
+	cfi_adjust_cfa_offset (-24)
+	cfi_restore (r0)
+	cfi_restore (r1)
+	cfi_restore (r2)
+	cfi_restore (r3)
+	cfi_register (lr, ip)
+	bx ip
+END(__gnu_mcount_nc)
+
+
+/* Provide old mcount for backwards compatibility.  This requires
+   code be compiled with APCS frame pointers.  */
+
+ENTRY(_mcount)
+	stmdb sp!, {r0, r1, r2, r3, fp, lr}
+	cfi_adjust_cfa_offset (24)
+	cfi_rel_offset (r0, 0)
+	cfi_rel_offset (r1, 4)
+	cfi_rel_offset (r2, 8)
+	cfi_rel_offset (r3, 12)
+	cfi_rel_offset (fp, 16)
+	cfi_rel_offset (lr, 20)
+#ifdef __thumb2__
+	movs r0, fp
+	ittt ne
+	ldrne r0, [r0, #-4]
+#else
+	movs fp, fp
+	ldrne r0, [fp, #-4]
+#endif
+	movnes r1, lr
+	blne __mcount_internal
+#ifdef __thumb2__
+	ldmia sp!, {r0, r1, r2, r3, fp, pc}
+#else
+	ldmia sp!, {r0, r1, r2, r3, fp, lr}
+	cfi_adjust_cfa_offset (-24)
+	cfi_restore (r0)
+	cfi_restore (r1)
+	cfi_restore (r2)
+	cfi_restore (r3)
+	cfi_restore (fp)
+	cfi_restore (lr)
+	bx lr
+#endif
+END(_mcount)
+
+/* The canonical name for the function is `_mcount' in both C and asm,
+   but some old asm code might assume it's `mcount'.  */
+#undef mcount
+weak_alias (_mcount, mcount)