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-rw-r--r--arch/ia64/lib/memcpy_mck.S659
1 files changed, 0 insertions, 659 deletions
diff --git a/arch/ia64/lib/memcpy_mck.S b/arch/ia64/lib/memcpy_mck.S
deleted file mode 100644
index c0d4362217..0000000000
--- a/arch/ia64/lib/memcpy_mck.S
+++ /dev/null
@@ -1,659 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Itanium 2-optimized version of memcpy and copy_user function
- *
- * Inputs:
- * in0: destination address
- * in1: source address
- * in2: number of bytes to copy
- * Output:
- * for memcpy: return dest
- * for copy_user: return 0 if success,
- * or number of byte NOT copied if error occurred.
- *
- * Copyright (C) 2002 Intel Corp.
- * Copyright (C) 2002 Ken Chen <kenneth.w.chen@intel.com>
- */
-#include <linux/export.h>
-#include <asm/asmmacro.h>
-#include <asm/page.h>
-
-#define EK(y...) EX(y)
-
-/* McKinley specific optimization */
-
-#define retval r8
-#define saved_pfs r31
-#define saved_lc r10
-#define saved_pr r11
-#define saved_in0 r14
-#define saved_in1 r15
-#define saved_in2 r16
-
-#define src0 r2
-#define src1 r3
-#define dst0 r17
-#define dst1 r18
-#define cnt r9
-
-/* r19-r30 are temp for each code section */
-#define PREFETCH_DIST 8
-#define src_pre_mem r19
-#define dst_pre_mem r20
-#define src_pre_l2 r21
-#define dst_pre_l2 r22
-#define t1 r23
-#define t2 r24
-#define t3 r25
-#define t4 r26
-#define t5 t1 // alias!
-#define t6 t2 // alias!
-#define t7 t3 // alias!
-#define n8 r27
-#define t9 t5 // alias!
-#define t10 t4 // alias!
-#define t11 t7 // alias!
-#define t12 t6 // alias!
-#define t14 t10 // alias!
-#define t13 r28
-#define t15 r29
-#define tmp r30
-
-/* defines for long_copy block */
-#define A 0
-#define B (PREFETCH_DIST)
-#define C (B + PREFETCH_DIST)
-#define D (C + 1)
-#define N (D + 1)
-#define Nrot ((N + 7) & ~7)
-
-/* alias */
-#define in0 r32
-#define in1 r33
-#define in2 r34
-
-GLOBAL_ENTRY(memcpy)
- and r28=0x7,in0
- and r29=0x7,in1
- mov f6=f0
- mov retval=in0
- br.cond.sptk .common_code
- ;;
-END(memcpy)
-EXPORT_SYMBOL(memcpy)
-GLOBAL_ENTRY(__copy_user)
- .prologue
-// check dest alignment
- and r28=0x7,in0
- and r29=0x7,in1
- mov f6=f1
- mov saved_in0=in0 // save dest pointer
- mov saved_in1=in1 // save src pointer
- mov retval=r0 // initialize return value
- ;;
-.common_code:
- cmp.gt p15,p0=8,in2 // check for small size
- cmp.ne p13,p0=0,r28 // check dest alignment
- cmp.ne p14,p0=0,r29 // check src alignment
- add src0=0,in1
- sub r30=8,r28 // for .align_dest
- mov saved_in2=in2 // save len
- ;;
- add dst0=0,in0
- add dst1=1,in0 // dest odd index
- cmp.le p6,p0 = 1,r30 // for .align_dest
-(p15) br.cond.dpnt .memcpy_short
-(p13) br.cond.dpnt .align_dest
-(p14) br.cond.dpnt .unaligned_src
- ;;
-
-// both dest and src are aligned on 8-byte boundary
-.aligned_src:
- .save ar.pfs, saved_pfs
- alloc saved_pfs=ar.pfs,3,Nrot-3,0,Nrot
- .save pr, saved_pr
- mov saved_pr=pr
-
- shr.u cnt=in2,7 // this much cache line
- ;;
- cmp.lt p6,p0=2*PREFETCH_DIST,cnt
- cmp.lt p7,p8=1,cnt
- .save ar.lc, saved_lc
- mov saved_lc=ar.lc
- .body
- add cnt=-1,cnt
- add src_pre_mem=0,in1 // prefetch src pointer
- add dst_pre_mem=0,in0 // prefetch dest pointer
- ;;
-(p7) mov ar.lc=cnt // prefetch count
-(p8) mov ar.lc=r0
-(p6) br.cond.dpnt .long_copy
- ;;
-
-.prefetch:
- lfetch.fault [src_pre_mem], 128
- lfetch.fault.excl [dst_pre_mem], 128
- br.cloop.dptk.few .prefetch
- ;;
-
-.medium_copy:
- and tmp=31,in2 // copy length after iteration
- shr.u r29=in2,5 // number of 32-byte iteration
- add dst1=8,dst0 // 2nd dest pointer
- ;;
- add cnt=-1,r29 // ctop iteration adjustment
- cmp.eq p10,p0=r29,r0 // do we really need to loop?
- add src1=8,src0 // 2nd src pointer
- cmp.le p6,p0=8,tmp
- ;;
- cmp.le p7,p0=16,tmp
- mov ar.lc=cnt // loop setup
- cmp.eq p16,p17 = r0,r0
- mov ar.ec=2
-(p10) br.dpnt.few .aligned_src_tail
- ;;
- TEXT_ALIGN(32)
-1:
-EX(.ex_handler, (p16) ld8 r34=[src0],16)
-EK(.ex_handler, (p16) ld8 r38=[src1],16)
-EX(.ex_handler, (p17) st8 [dst0]=r33,16)
-EK(.ex_handler, (p17) st8 [dst1]=r37,16)
- ;;
-EX(.ex_handler, (p16) ld8 r32=[src0],16)
-EK(.ex_handler, (p16) ld8 r36=[src1],16)
-EX(.ex_handler, (p16) st8 [dst0]=r34,16)
-EK(.ex_handler, (p16) st8 [dst1]=r38,16)
- br.ctop.dptk.few 1b
- ;;
-
-.aligned_src_tail:
-EX(.ex_handler, (p6) ld8 t1=[src0])
- mov ar.lc=saved_lc
- mov ar.pfs=saved_pfs
-EX(.ex_hndlr_s, (p7) ld8 t2=[src1],8)
- cmp.le p8,p0=24,tmp
- and r21=-8,tmp
- ;;
-EX(.ex_hndlr_s, (p8) ld8 t3=[src1])
-EX(.ex_handler, (p6) st8 [dst0]=t1) // store byte 1
- and in2=7,tmp // remaining length
-EX(.ex_hndlr_d, (p7) st8 [dst1]=t2,8) // store byte 2
- add src0=src0,r21 // setting up src pointer
- add dst0=dst0,r21 // setting up dest pointer
- ;;
-EX(.ex_handler, (p8) st8 [dst1]=t3) // store byte 3
- mov pr=saved_pr,-1
- br.dptk.many .memcpy_short
- ;;
-
-/* code taken from copy_page_mck */
-.long_copy:
- .rotr v[2*PREFETCH_DIST]
- .rotp p[N]
-
- mov src_pre_mem = src0
- mov pr.rot = 0x10000
- mov ar.ec = 1 // special unrolled loop
-
- mov dst_pre_mem = dst0
-
- add src_pre_l2 = 8*8, src0
- add dst_pre_l2 = 8*8, dst0
- ;;
- add src0 = 8, src_pre_mem // first t1 src
- mov ar.lc = 2*PREFETCH_DIST - 1
- shr.u cnt=in2,7 // number of lines
- add src1 = 3*8, src_pre_mem // first t3 src
- add dst0 = 8, dst_pre_mem // first t1 dst
- add dst1 = 3*8, dst_pre_mem // first t3 dst
- ;;
- and tmp=127,in2 // remaining bytes after this block
- add cnt = -(2*PREFETCH_DIST) - 1, cnt
- // same as .line_copy loop, but with all predicated-off instructions removed:
-.prefetch_loop:
-EX(.ex_hndlr_lcpy_1, (p[A]) ld8 v[A] = [src_pre_mem], 128) // M0
-EK(.ex_hndlr_lcpy_1, (p[B]) st8 [dst_pre_mem] = v[B], 128) // M2
- br.ctop.sptk .prefetch_loop
- ;;
- cmp.eq p16, p0 = r0, r0 // reset p16 to 1
- mov ar.lc = cnt
- mov ar.ec = N // # of stages in pipeline
- ;;
-.line_copy:
-EX(.ex_handler, (p[D]) ld8 t2 = [src0], 3*8) // M0
-EK(.ex_handler, (p[D]) ld8 t4 = [src1], 3*8) // M1
-EX(.ex_handler_lcpy, (p[B]) st8 [dst_pre_mem] = v[B], 128) // M2 prefetch dst from memory
-EK(.ex_handler_lcpy, (p[D]) st8 [dst_pre_l2] = n8, 128) // M3 prefetch dst from L2
- ;;
-EX(.ex_handler_lcpy, (p[A]) ld8 v[A] = [src_pre_mem], 128) // M0 prefetch src from memory
-EK(.ex_handler_lcpy, (p[C]) ld8 n8 = [src_pre_l2], 128) // M1 prefetch src from L2
-EX(.ex_handler, (p[D]) st8 [dst0] = t1, 8) // M2
-EK(.ex_handler, (p[D]) st8 [dst1] = t3, 8) // M3
- ;;
-EX(.ex_handler, (p[D]) ld8 t5 = [src0], 8)
-EK(.ex_handler, (p[D]) ld8 t7 = [src1], 3*8)
-EX(.ex_handler, (p[D]) st8 [dst0] = t2, 3*8)
-EK(.ex_handler, (p[D]) st8 [dst1] = t4, 3*8)
- ;;
-EX(.ex_handler, (p[D]) ld8 t6 = [src0], 3*8)
-EK(.ex_handler, (p[D]) ld8 t10 = [src1], 8)
-EX(.ex_handler, (p[D]) st8 [dst0] = t5, 8)
-EK(.ex_handler, (p[D]) st8 [dst1] = t7, 3*8)
- ;;
-EX(.ex_handler, (p[D]) ld8 t9 = [src0], 3*8)
-EK(.ex_handler, (p[D]) ld8 t11 = [src1], 3*8)
-EX(.ex_handler, (p[D]) st8 [dst0] = t6, 3*8)
-EK(.ex_handler, (p[D]) st8 [dst1] = t10, 8)
- ;;
-EX(.ex_handler, (p[D]) ld8 t12 = [src0], 8)
-EK(.ex_handler, (p[D]) ld8 t14 = [src1], 8)
-EX(.ex_handler, (p[D]) st8 [dst0] = t9, 3*8)
-EK(.ex_handler, (p[D]) st8 [dst1] = t11, 3*8)
- ;;
-EX(.ex_handler, (p[D]) ld8 t13 = [src0], 4*8)
-EK(.ex_handler, (p[D]) ld8 t15 = [src1], 4*8)
-EX(.ex_handler, (p[D]) st8 [dst0] = t12, 8)
-EK(.ex_handler, (p[D]) st8 [dst1] = t14, 8)
- ;;
-EX(.ex_handler, (p[C]) ld8 t1 = [src0], 8)
-EK(.ex_handler, (p[C]) ld8 t3 = [src1], 8)
-EX(.ex_handler, (p[D]) st8 [dst0] = t13, 4*8)
-EK(.ex_handler, (p[D]) st8 [dst1] = t15, 4*8)
- br.ctop.sptk .line_copy
- ;;
-
- add dst0=-8,dst0
- add src0=-8,src0
- mov in2=tmp
- .restore sp
- br.sptk.many .medium_copy
- ;;
-
-#define BLOCK_SIZE 128*32
-#define blocksize r23
-#define curlen r24
-
-// dest is on 8-byte boundary, src is not. We need to do
-// ld8-ld8, shrp, then st8. Max 8 byte copy per cycle.
-.unaligned_src:
- .prologue
- .save ar.pfs, saved_pfs
- alloc saved_pfs=ar.pfs,3,5,0,8
- .save ar.lc, saved_lc
- mov saved_lc=ar.lc
- .save pr, saved_pr
- mov saved_pr=pr
- .body
-.4k_block:
- mov saved_in0=dst0 // need to save all input arguments
- mov saved_in2=in2
- mov blocksize=BLOCK_SIZE
- ;;
- cmp.lt p6,p7=blocksize,in2
- mov saved_in1=src0
- ;;
-(p6) mov in2=blocksize
- ;;
- shr.u r21=in2,7 // this much cache line
- shr.u r22=in2,4 // number of 16-byte iteration
- and curlen=15,in2 // copy length after iteration
- and r30=7,src0 // source alignment
- ;;
- cmp.lt p7,p8=1,r21
- add cnt=-1,r21
- ;;
-
- add src_pre_mem=0,src0 // prefetch src pointer
- add dst_pre_mem=0,dst0 // prefetch dest pointer
- and src0=-8,src0 // 1st src pointer
-(p7) mov ar.lc = cnt
-(p8) mov ar.lc = r0
- ;;
- TEXT_ALIGN(32)
-1: lfetch.fault [src_pre_mem], 128
- lfetch.fault.excl [dst_pre_mem], 128
- br.cloop.dptk.few 1b
- ;;
-
- shladd dst1=r22,3,dst0 // 2nd dest pointer
- shladd src1=r22,3,src0 // 2nd src pointer
- cmp.eq p8,p9=r22,r0 // do we really need to loop?
- cmp.le p6,p7=8,curlen; // have at least 8 byte remaining?
- add cnt=-1,r22 // ctop iteration adjustment
- ;;
-EX(.ex_handler, (p9) ld8 r33=[src0],8) // loop primer
-EK(.ex_handler, (p9) ld8 r37=[src1],8)
-(p8) br.dpnt.few .noloop
- ;;
-
-// The jump address is calculated based on src alignment. The COPYU
-// macro below need to confine its size to power of two, so an entry
-// can be caulated using shl instead of an expensive multiply. The
-// size is then hard coded by the following #define to match the
-// actual size. This make it somewhat tedious when COPYU macro gets
-// changed and this need to be adjusted to match.
-#define LOOP_SIZE 6
-1:
- mov r29=ip // jmp_table thread
- mov ar.lc=cnt
- ;;
- add r29=.jump_table - 1b - (.jmp1-.jump_table), r29
- shl r28=r30, LOOP_SIZE // jmp_table thread
- mov ar.ec=2 // loop setup
- ;;
- add r29=r29,r28 // jmp_table thread
- cmp.eq p16,p17=r0,r0
- ;;
- mov b6=r29 // jmp_table thread
- ;;
- br.cond.sptk.few b6
-
-// for 8-15 byte case
-// We will skip the loop, but need to replicate the side effect
-// that the loop produces.
-.noloop:
-EX(.ex_handler, (p6) ld8 r37=[src1],8)
- add src0=8,src0
-(p6) shl r25=r30,3
- ;;
-EX(.ex_handler, (p6) ld8 r27=[src1])
-(p6) shr.u r28=r37,r25
-(p6) sub r26=64,r25
- ;;
-(p6) shl r27=r27,r26
- ;;
-(p6) or r21=r28,r27
-
-.unaligned_src_tail:
-/* check if we have more than blocksize to copy, if so go back */
- cmp.gt p8,p0=saved_in2,blocksize
- ;;
-(p8) add dst0=saved_in0,blocksize
-(p8) add src0=saved_in1,blocksize
-(p8) sub in2=saved_in2,blocksize
-(p8) br.dpnt .4k_block
- ;;
-
-/* we have up to 15 byte to copy in the tail.
- * part of work is already done in the jump table code
- * we are at the following state.
- * src side:
- *
- * xxxxxx xx <----- r21 has xxxxxxxx already
- * -------- -------- --------
- * 0 8 16
- * ^
- * |
- * src1
- *
- * dst
- * -------- -------- --------
- * ^
- * |
- * dst1
- */
-EX(.ex_handler, (p6) st8 [dst1]=r21,8) // more than 8 byte to copy
-(p6) add curlen=-8,curlen // update length
- mov ar.pfs=saved_pfs
- ;;
- mov ar.lc=saved_lc
- mov pr=saved_pr,-1
- mov in2=curlen // remaining length
- mov dst0=dst1 // dest pointer
- add src0=src1,r30 // forward by src alignment
- ;;
-
-// 7 byte or smaller.
-.memcpy_short:
- cmp.le p8,p9 = 1,in2
- cmp.le p10,p11 = 2,in2
- cmp.le p12,p13 = 3,in2
- cmp.le p14,p15 = 4,in2
- add src1=1,src0 // second src pointer
- add dst1=1,dst0 // second dest pointer
- ;;
-
-EX(.ex_handler_short, (p8) ld1 t1=[src0],2)
-EK(.ex_handler_short, (p10) ld1 t2=[src1],2)
-(p9) br.ret.dpnt rp // 0 byte copy
- ;;
-
-EX(.ex_handler_short, (p8) st1 [dst0]=t1,2)
-EK(.ex_handler_short, (p10) st1 [dst1]=t2,2)
-(p11) br.ret.dpnt rp // 1 byte copy
-
-EX(.ex_handler_short, (p12) ld1 t3=[src0],2)
-EK(.ex_handler_short, (p14) ld1 t4=[src1],2)
-(p13) br.ret.dpnt rp // 2 byte copy
- ;;
-
- cmp.le p6,p7 = 5,in2
- cmp.le p8,p9 = 6,in2
- cmp.le p10,p11 = 7,in2
-
-EX(.ex_handler_short, (p12) st1 [dst0]=t3,2)
-EK(.ex_handler_short, (p14) st1 [dst1]=t4,2)
-(p15) br.ret.dpnt rp // 3 byte copy
- ;;
-
-EX(.ex_handler_short, (p6) ld1 t5=[src0],2)
-EK(.ex_handler_short, (p8) ld1 t6=[src1],2)
-(p7) br.ret.dpnt rp // 4 byte copy
- ;;
-
-EX(.ex_handler_short, (p6) st1 [dst0]=t5,2)
-EK(.ex_handler_short, (p8) st1 [dst1]=t6,2)
-(p9) br.ret.dptk rp // 5 byte copy
-
-EX(.ex_handler_short, (p10) ld1 t7=[src0],2)
-(p11) br.ret.dptk rp // 6 byte copy
- ;;
-
-EX(.ex_handler_short, (p10) st1 [dst0]=t7,2)
- br.ret.dptk rp // done all cases
-
-
-/* Align dest to nearest 8-byte boundary. We know we have at
- * least 7 bytes to copy, enough to crawl to 8-byte boundary.
- * Actual number of byte to crawl depend on the dest alignment.
- * 7 byte or less is taken care at .memcpy_short
-
- * src0 - source even index
- * src1 - source odd index
- * dst0 - dest even index
- * dst1 - dest odd index
- * r30 - distance to 8-byte boundary
- */
-
-.align_dest:
- add src1=1,in1 // source odd index
- cmp.le p7,p0 = 2,r30 // for .align_dest
- cmp.le p8,p0 = 3,r30 // for .align_dest
-EX(.ex_handler_short, (p6) ld1 t1=[src0],2)
- cmp.le p9,p0 = 4,r30 // for .align_dest
- cmp.le p10,p0 = 5,r30
- ;;
-EX(.ex_handler_short, (p7) ld1 t2=[src1],2)
-EK(.ex_handler_short, (p8) ld1 t3=[src0],2)
- cmp.le p11,p0 = 6,r30
-EX(.ex_handler_short, (p6) st1 [dst0] = t1,2)
- cmp.le p12,p0 = 7,r30
- ;;
-EX(.ex_handler_short, (p9) ld1 t4=[src1],2)
-EK(.ex_handler_short, (p10) ld1 t5=[src0],2)
-EX(.ex_handler_short, (p7) st1 [dst1] = t2,2)
-EK(.ex_handler_short, (p8) st1 [dst0] = t3,2)
- ;;
-EX(.ex_handler_short, (p11) ld1 t6=[src1],2)
-EK(.ex_handler_short, (p12) ld1 t7=[src0],2)
- cmp.eq p6,p7=r28,r29
-EX(.ex_handler_short, (p9) st1 [dst1] = t4,2)
-EK(.ex_handler_short, (p10) st1 [dst0] = t5,2)
- sub in2=in2,r30
- ;;
-EX(.ex_handler_short, (p11) st1 [dst1] = t6,2)
-EK(.ex_handler_short, (p12) st1 [dst0] = t7)
- add dst0=in0,r30 // setup arguments
- add src0=in1,r30
-(p6) br.cond.dptk .aligned_src
-(p7) br.cond.dpnt .unaligned_src
- ;;
-
-/* main loop body in jump table format */
-#define COPYU(shift) \
-1: \
-EX(.ex_handler, (p16) ld8 r32=[src0],8); /* 1 */ \
-EK(.ex_handler, (p16) ld8 r36=[src1],8); \
- (p17) shrp r35=r33,r34,shift;; /* 1 */ \
-EX(.ex_handler, (p6) ld8 r22=[src1]); /* common, prime for tail section */ \
- nop.m 0; \
- (p16) shrp r38=r36,r37,shift; \
-EX(.ex_handler, (p17) st8 [dst0]=r35,8); /* 1 */ \
-EK(.ex_handler, (p17) st8 [dst1]=r39,8); \
- br.ctop.dptk.few 1b;; \
- (p7) add src1=-8,src1; /* back out for <8 byte case */ \
- shrp r21=r22,r38,shift; /* speculative work */ \
- br.sptk.few .unaligned_src_tail /* branch out of jump table */ \
- ;;
- TEXT_ALIGN(32)
-.jump_table:
- COPYU(8) // unaligned cases
-.jmp1:
- COPYU(16)
- COPYU(24)
- COPYU(32)
- COPYU(40)
- COPYU(48)
- COPYU(56)
-
-#undef A
-#undef B
-#undef C
-#undef D
-
-/*
- * Due to lack of local tag support in gcc 2.x assembler, it is not clear which
- * instruction failed in the bundle. The exception algorithm is that we
- * first figure out the faulting address, then detect if there is any
- * progress made on the copy, if so, redo the copy from last known copied
- * location up to the faulting address (exclusive). In the copy_from_user
- * case, remaining byte in kernel buffer will be zeroed.
- *
- * Take copy_from_user as an example, in the code there are multiple loads
- * in a bundle and those multiple loads could span over two pages, the
- * faulting address is calculated as page_round_down(max(src0, src1)).
- * This is based on knowledge that if we can access one byte in a page, we
- * can access any byte in that page.
- *
- * predicate used in the exception handler:
- * p6-p7: direction
- * p10-p11: src faulting addr calculation
- * p12-p13: dst faulting addr calculation
- */
-
-#define A r19
-#define B r20
-#define C r21
-#define D r22
-#define F r28
-
-#define saved_retval loc0
-#define saved_rtlink loc1
-#define saved_pfs_stack loc2
-
-.ex_hndlr_s:
- add src0=8,src0
- br.sptk .ex_handler
- ;;
-.ex_hndlr_d:
- add dst0=8,dst0
- br.sptk .ex_handler
- ;;
-.ex_hndlr_lcpy_1:
- mov src1=src_pre_mem
- mov dst1=dst_pre_mem
- cmp.gtu p10,p11=src_pre_mem,saved_in1
- cmp.gtu p12,p13=dst_pre_mem,saved_in0
- ;;
-(p10) add src0=8,saved_in1
-(p11) mov src0=saved_in1
-(p12) add dst0=8,saved_in0
-(p13) mov dst0=saved_in0
- br.sptk .ex_handler
-.ex_handler_lcpy:
- // in line_copy block, the preload addresses should always ahead
- // of the other two src/dst pointers. Furthermore, src1/dst1 should
- // always ahead of src0/dst0.
- mov src1=src_pre_mem
- mov dst1=dst_pre_mem
-.ex_handler:
- mov pr=saved_pr,-1 // first restore pr, lc, and pfs
- mov ar.lc=saved_lc
- mov ar.pfs=saved_pfs
- ;;
-.ex_handler_short: // fault occurred in these sections didn't change pr, lc, pfs
- cmp.ltu p6,p7=saved_in0, saved_in1 // get the copy direction
- cmp.ltu p10,p11=src0,src1
- cmp.ltu p12,p13=dst0,dst1
- fcmp.eq p8,p0=f6,f0 // is it memcpy?
- mov tmp = dst0
- ;;
-(p11) mov src1 = src0 // pick the larger of the two
-(p13) mov dst0 = dst1 // make dst0 the smaller one
-(p13) mov dst1 = tmp // and dst1 the larger one
- ;;
-(p6) dep F = r0,dst1,0,PAGE_SHIFT // usr dst round down to page boundary
-(p7) dep F = r0,src1,0,PAGE_SHIFT // usr src round down to page boundary
- ;;
-(p6) cmp.le p14,p0=dst0,saved_in0 // no progress has been made on store
-(p7) cmp.le p14,p0=src0,saved_in1 // no progress has been made on load
- mov retval=saved_in2
-(p8) ld1 tmp=[src1] // force an oops for memcpy call
-(p8) st1 [dst1]=r0 // force an oops for memcpy call
-(p14) br.ret.sptk.many rp
-
-/*
- * The remaining byte to copy is calculated as:
- *
- * A = (faulting_addr - orig_src) -> len to faulting ld address
- * or
- * (faulting_addr - orig_dst) -> len to faulting st address
- * B = (cur_dst - orig_dst) -> len copied so far
- * C = A - B -> len need to be copied
- * D = orig_len - A -> len need to be left along
- */
-(p6) sub A = F, saved_in0
-(p7) sub A = F, saved_in1
- clrrrb
- ;;
- alloc saved_pfs_stack=ar.pfs,3,3,3,0
- cmp.lt p8,p0=A,r0
- sub B = dst0, saved_in0 // how many byte copied so far
- ;;
-(p8) mov A = 0; // A shouldn't be negative, cap it
- ;;
- sub C = A, B
- sub D = saved_in2, A
- ;;
- cmp.gt p8,p0=C,r0 // more than 1 byte?
- mov r8=0
- mov saved_retval = D
- mov saved_rtlink = b0
-
- add out0=saved_in0, B
- add out1=saved_in1, B
- mov out2=C
-(p8) br.call.sptk.few b0=__copy_user // recursive call
- ;;
-
- add saved_retval=saved_retval,r8 // above might return non-zero value
- ;;
-
- mov retval=saved_retval
- mov ar.pfs=saved_pfs_stack
- mov b0=saved_rtlink
- br.ret.sptk.many rp
-
-/* end of McKinley specific optimization */
-END(__copy_user)
-EXPORT_SYMBOL(__copy_user)
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 11:41:12 +0000