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-rw-r--r--libc/string/arc/arcv2/memcpy.S236
1 files changed, 236 insertions, 0 deletions
diff --git a/libc/string/arc/arcv2/memcpy.S b/libc/string/arc/arcv2/memcpy.S
new file mode 100644
index 000000000..7573daf51
--- /dev/null
+++ b/libc/string/arc/arcv2/memcpy.S
@@ -0,0 +1,236 @@
+/*
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball.
+ */
+
+#include <features.h>
+#include <sysdep.h>
+
+#ifdef __LITTLE_ENDIAN__
+# define SHIFT_1(RX,RY,IMM) asl RX, RY, IMM ; <<
+# define SHIFT_2(RX,RY,IMM) lsr RX, RY, IMM ; >>
+# define MERGE_1(RX,RY,IMM) asl RX, RY, IMM
+# define MERGE_2(RX,RY,IMM)
+# define EXTRACT_1(RX,RY,IMM) and RX, RY, 0xFFFF
+# define EXTRACT_2(RX,RY,IMM) lsr RX, RY, IMM
+#else
+# define SHIFT_1(RX,RY,IMM) lsr RX, RY, IMM ; >>
+# define SHIFT_2(RX,RY,IMM) asl RX, RY, IMM ; <<
+# define MERGE_1(RX,RY,IMM) asl RX, RY, IMM ; <<
+# define MERGE_2(RX,RY,IMM) asl RX, RY, IMM ; <<
+# define EXTRACT_1(RX,RY,IMM) lsr RX, RY, IMM
+# define EXTRACT_2(RX,RY,IMM) lsr RX, RY, 0x08
+#endif
+
+#ifdef __LL64__
+# define PREFETCH_READ(RX) prefetch [RX, 56]
+# define PREFETCH_WRITE(RX) prefetchw [RX, 64]
+# define LOADX(DST,RX) ldd.ab DST, [RX, 8]
+# define STOREX(SRC,RX) std.ab SRC, [RX, 8]
+# define ZOLSHFT 5
+# define ZOLAND 0x1F
+#else
+# define PREFETCH_READ(RX) prefetch [RX, 28]
+# define PREFETCH_WRITE(RX) prefetchw [RX, 32]
+# define LOADX(DST,RX) ld.ab DST, [RX, 4]
+# define STOREX(SRC,RX) st.ab SRC, [RX, 4]
+# define ZOLSHFT 4
+# define ZOLAND 0xF
+#endif
+
+ENTRY(memcpy)
+ prefetch [r1] ; Prefetch the read location
+ prefetchw [r0] ; Prefetch the write location
+ mov.f 0, r2
+;;; if size is zero
+ jz.d [blink]
+ mov r3, r0 ; don't clobber ret val
+
+;;; if size <= 8
+ cmp r2, 8
+ bls.d @.Lsmallchunk
+ mov.f lp_count, r2
+
+ and.f r4, r0, 0x03
+ rsub lp_count, r4, 4
+ lpnz @.Laligndestination
+ ;; LOOP BEGIN
+ ldb.ab r5, [r1,1]
+ sub r2, r2, 1
+ stb.ab r5, [r3,1]
+.Laligndestination:
+
+;;; Check the alignment of the source
+ and.f r4, r1, 0x03
+ bnz.d @.Lsourceunaligned
+
+;;; CASE 0: Both source and destination are 32bit aligned
+;;; Convert len to Dwords, unfold x4
+ lsr.f lp_count, r2, ZOLSHFT
+ lpnz @.Lcopy32_64bytes
+ ;; LOOP START
+ LOADX (r6, r1)
+ PREFETCH_READ (r1)
+ PREFETCH_WRITE (r3)
+ LOADX (r8, r1)
+ LOADX (r10, r1)
+ LOADX (r4, r1)
+ STOREX (r6, r3)
+ STOREX (r8, r3)
+ STOREX (r10, r3)
+ STOREX (r4, r3)
+.Lcopy32_64bytes:
+
+ and.f lp_count, r2, ZOLAND ;Last remaining 31 bytes
+.Lsmallchunk:
+ lpnz @.Lcopyremainingbytes
+ ;; LOOP START
+ ldb.ab r5, [r1,1]
+ stb.ab r5, [r3,1]
+.Lcopyremainingbytes:
+
+ j [blink]
+;;; END CASE 0
+
+.Lsourceunaligned:
+ cmp r4, 2
+ beq.d @.LunalignedOffby2
+ sub r2, r2, 1
+
+ bhi.d @.LunalignedOffby3
+ ldb.ab r5, [r1, 1]
+
+;;; CASE 1: The source is unaligned, off by 1
+ ;; Hence I need to read 1 byte for a 16bit alignment
+ ;; and 2bytes to reach 32bit alignment
+ ldh.ab r6, [r1, 2]
+ sub r2, r2, 2
+ ;; Convert to words, unfold x2
+ lsr.f lp_count, r2, 3
+ MERGE_1 (r6, r6, 8)
+ MERGE_2 (r5, r5, 24)
+ or r5, r5, r6
+
+ ;; Both src and dst are aligned
+ lpnz @.Lcopy8bytes_1
+ ;; LOOP START
+ ld.ab r6, [r1, 4]
+ prefetch [r1, 28] ;Prefetch the next read location
+ ld.ab r8, [r1,4]
+ prefetchw [r3, 32] ;Prefetch the next write location
+
+ SHIFT_1 (r7, r6, 24)
+ or r7, r7, r5
+ SHIFT_2 (r5, r6, 8)
+
+ SHIFT_1 (r9, r8, 24)
+ or r9, r9, r5
+ SHIFT_2 (r5, r8, 8)
+
+ st.ab r7, [r3, 4]
+ st.ab r9, [r3, 4]
+.Lcopy8bytes_1:
+
+ ;; Write back the remaining 16bits
+ EXTRACT_1 (r6, r5, 16)
+ sth.ab r6, [r3, 2]
+ ;; Write back the remaining 8bits
+ EXTRACT_2 (r5, r5, 16)
+ stb.ab r5, [r3, 1]
+
+ and.f lp_count, r2, 0x07 ;Last 8bytes
+ lpnz @.Lcopybytewise_1
+ ;; LOOP START
+ ldb.ab r6, [r1,1]
+ stb.ab r6, [r3,1]
+.Lcopybytewise_1:
+ j [blink]
+
+.LunalignedOffby2:
+;;; CASE 2: The source is unaligned, off by 2
+ ldh.ab r5, [r1, 2]
+ sub r2, r2, 1
+
+ ;; Both src and dst are aligned
+ ;; Convert to words, unfold x2
+ lsr.f lp_count, r2, 3
+#ifdef __BIG_ENDIAN__
+ asl.nz r5, r5, 16
+#endif
+ lpnz @.Lcopy8bytes_2
+ ;; LOOP START
+ ld.ab r6, [r1, 4]
+ prefetch [r1, 28] ;Prefetch the next read location
+ ld.ab r8, [r1,4]
+ prefetchw [r3, 32] ;Prefetch the next write location
+
+ SHIFT_1 (r7, r6, 16)
+ or r7, r7, r5
+ SHIFT_2 (r5, r6, 16)
+
+ SHIFT_1 (r9, r8, 16)
+ or r9, r9, r5
+ SHIFT_2 (r5, r8, 16)
+
+ st.ab r7, [r3, 4]
+ st.ab r9, [r3, 4]
+.Lcopy8bytes_2:
+
+#ifdef __BIG_ENDIAN__
+ lsr.nz r5, r5, 16
+#endif
+ sth.ab r5, [r3, 2]
+
+ and.f lp_count, r2, 0x07 ;Last 8bytes
+ lpnz @.Lcopybytewise_2
+ ;; LOOP START
+ ldb.ab r6, [r1,1]
+ stb.ab r6, [r3,1]
+.Lcopybytewise_2:
+ j [blink]
+
+.LunalignedOffby3:
+;;; CASE 3: The source is unaligned, off by 3
+;;; Hence, I need to read 1byte for achieve the 32bit alignment
+
+ ;; Both src and dst are aligned
+ ;; Convert to words, unfold x2
+ lsr.f lp_count, r2, 3
+#ifdef __BIG_ENDIAN__
+ asl.ne r5, r5, 24
+#endif
+ lpnz @.Lcopy8bytes_3
+ ;; LOOP START
+ ld.ab r6, [r1, 4]
+ prefetch [r1, 28] ;Prefetch the next read location
+ ld.ab r8, [r1,4]
+ prefetchw [r3, 32] ;Prefetch the next write location
+
+ SHIFT_1 (r7, r6, 8)
+ or r7, r7, r5
+ SHIFT_2 (r5, r6, 24)
+
+ SHIFT_1 (r9, r8, 8)
+ or r9, r9, r5
+ SHIFT_2 (r5, r8, 24)
+
+ st.ab r7, [r3, 4]
+ st.ab r9, [r3, 4]
+.Lcopy8bytes_3:
+
+#ifdef __BIG_ENDIAN__
+ lsr.nz r5, r5, 24
+#endif
+ stb.ab r5, [r3, 1]
+
+ and.f lp_count, r2, 0x07 ;Last 8bytes
+ lpnz @.Lcopybytewise_3
+ ;; LOOP START
+ ldb.ab r6, [r1,1]
+ stb.ab r6, [r3,1]
+.Lcopybytewise_3:
+ j [blink]
+
+END(memcpy)
+libc_hidden_def(memcpy)