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Diffstat (limited to 'gcc/config/xtensa/lib2funcs.S')
| -rw-r--r-- | gcc/config/xtensa/lib2funcs.S | 186 |
1 files changed, 0 insertions, 186 deletions
diff --git a/gcc/config/xtensa/lib2funcs.S b/gcc/config/xtensa/lib2funcs.S deleted file mode 100644 index 65134e24ccf..00000000000 --- a/gcc/config/xtensa/lib2funcs.S +++ /dev/null @@ -1,186 +0,0 @@ -/* Assembly functions for libgcc2. - Copyright (C) 2001, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. - Contributed by Bob Wilson (bwilson@tensilica.com) at Tensilica. - -This file is part of GCC. - -GCC is free software; you can redistribute it and/or modify it under -the terms of the GNU General Public License as published by the Free -Software Foundation; either version 3, or (at your option) any later -version. - -GCC 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 General Public License -for more details. - -Under Section 7 of GPL version 3, you are granted additional -permissions described in the GCC Runtime Library Exception, version -3.1, as published by the Free Software Foundation. - -You should have received a copy of the GNU General Public License and -a copy of the GCC Runtime Library Exception along with this program; -see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -<http://www.gnu.org/licenses/>. */ - -#include "xtensa-config.h" - -/* __xtensa_libgcc_window_spill: This function flushes out all but the - current register window. This is used to set up the stack so that - arbitrary frames can be accessed. */ - - .align 4 - .global __xtensa_libgcc_window_spill - .type __xtensa_libgcc_window_spill,@function -__xtensa_libgcc_window_spill: - entry sp, 32 - movi a2, 0 - syscall - retw - .size __xtensa_libgcc_window_spill, .-__xtensa_libgcc_window_spill - - -/* __xtensa_nonlocal_goto: This code does all the hard work of a - nonlocal goto on Xtensa. It is here in the library to avoid the - code size bloat of generating it in-line. There are two - arguments: - - a2 = frame pointer for the procedure containing the label - a3 = goto handler address - - This function never returns to its caller but instead goes directly - to the address of the specified goto handler. */ - - .align 4 - .global __xtensa_nonlocal_goto - .type __xtensa_nonlocal_goto,@function -__xtensa_nonlocal_goto: - entry sp, 32 - - /* Flush registers. */ - mov a5, a2 - movi a2, 0 - syscall - mov a2, a5 - - /* Because the save area for a0-a3 is stored one frame below - the one identified by a2, the only way to restore those - registers is to unwind the stack. If alloca() were never - called, we could just unwind until finding the sp value - matching a2. However, a2 is a frame pointer, not a stack - pointer, and may not be encountered during the unwinding. - The solution is to unwind until going _past_ the value - given by a2. This involves keeping three stack pointer - values during the unwinding: - - next = sp of frame N-1 - cur = sp of frame N - prev = sp of frame N+1 - - When next > a2, the desired save area is stored relative - to prev. At this point, cur will be the same as a2 - except in the alloca() case. - - Besides finding the values to be restored to a0-a3, we also - need to find the current window size for the target - function. This can be extracted from the high bits of the - return address, initially in a0. As the unwinding - proceeds, the window size is taken from the value of a0 - saved _two_ frames below the current frame. */ - - addi a5, sp, -16 /* a5 = prev - save area */ - l32i a6, a5, 4 - addi a6, a6, -16 /* a6 = cur - save area */ - mov a8, a0 /* a8 = return address (for window size) */ - j .Lfirstframe - -.Lnextframe: - l32i a8, a5, 0 /* next return address (for window size) */ - mov a5, a6 /* advance prev */ - addi a6, a7, -16 /* advance cur */ -.Lfirstframe: - l32i a7, a6, 4 /* a7 = next */ - bgeu a2, a7, .Lnextframe - - /* At this point, prev (a5) points to the save area with the saved - values of a0-a3. Copy those values into the save area at the - current sp so they will be reloaded when the return from this - function underflows. We don't have to worry about exceptions - while updating the current save area, because the windows have - already been flushed. */ - - addi a4, sp, -16 /* a4 = save area of this function */ - l32i a6, a5, 0 - l32i a7, a5, 4 - s32i a6, a4, 0 - s32i a7, a4, 4 - l32i a6, a5, 8 - l32i a7, a5, 12 - s32i a6, a4, 8 - s32i a7, a4, 12 - - /* Set return address to goto handler. Use the window size bits - from the return address two frames below the target. */ - extui a8, a8, 30, 2 /* get window size from return addr. */ - slli a3, a3, 2 /* get goto handler addr. << 2 */ - ssai 2 - src a0, a8, a3 /* combine them with a funnel shift */ - - retw - .size __xtensa_nonlocal_goto, .-__xtensa_nonlocal_goto - - -/* __xtensa_sync_caches: This function is called after writing a trampoline - on the stack to force all the data writes to memory and invalidate the - instruction cache. a2 is the address of the new trampoline. - - After the trampoline data is written out, it must be flushed out of - the data cache into memory. We use DHWB in case we have a writeback - cache. At least one DHWB instruction is needed for each data cache - line which may be touched by the trampoline. An ISYNC instruction - must follow the DHWBs. - - We have to flush the i-cache to make sure that the new values get used. - At least one IHI instruction is needed for each i-cache line which may - be touched by the trampoline. An ISYNC instruction is also needed to - make sure that the modified instructions are loaded into the instruction - fetch buffer. */ - -/* Use the maximum trampoline size. Flushing a bit extra is OK. */ -#define TRAMPOLINE_SIZE 60 - - .text - .align 4 - .global __xtensa_sync_caches - .type __xtensa_sync_caches,@function -__xtensa_sync_caches: - entry sp, 32 -#if XCHAL_DCACHE_SIZE > 0 - /* Flush the trampoline from the data cache. */ - extui a4, a2, 0, XCHAL_DCACHE_LINEWIDTH - addi a4, a4, TRAMPOLINE_SIZE - addi a4, a4, (1 << XCHAL_DCACHE_LINEWIDTH) - 1 - srli a4, a4, XCHAL_DCACHE_LINEWIDTH - mov a3, a2 -.Ldcache_loop: - dhwb a3, 0 - addi a3, a3, (1 << XCHAL_DCACHE_LINEWIDTH) - addi a4, a4, -1 - bnez a4, .Ldcache_loop - isync -#endif -#if XCHAL_ICACHE_SIZE > 0 - /* Invalidate the corresponding lines in the instruction cache. */ - extui a4, a2, 0, XCHAL_ICACHE_LINEWIDTH - addi a4, a4, TRAMPOLINE_SIZE - addi a4, a4, (1 << XCHAL_ICACHE_LINEWIDTH) - 1 - srli a4, a4, XCHAL_ICACHE_LINEWIDTH -.Licache_loop: - ihi a2, 0 - addi a2, a2, (1 << XCHAL_ICACHE_LINEWIDTH) - addi a4, a4, -1 - bnez a4, .Licache_loop -#endif - isync - retw - .size __xtensa_sync_caches, .-__xtensa_sync_caches |