From afab56958f1cbb47b831ee3ebff231dfbae74af2 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Thu, 19 Feb 2015 19:13:59 +0530 Subject: ARCv2 ISA support This is next gen Instruction Set Architecture from Synopsys and basis for the ARC HS family of processors. http://www.synopsys.com/dw/ipdir.php?ds=arc-hs38-processor&elq_mid=5732&elq_cid=458802 http://www.synopsys.com/IP/ProcessorIP/ARCProcessors/arc-hs/Pages/default.aspx Signed-off-by: Vineet Gupta Signed-off-by: Bernhard Reutner-Fischer --- libc/string/arc/memcmp.S | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'libc/string/arc') diff --git a/libc/string/arc/memcmp.S b/libc/string/arc/memcmp.S index 4c0e39143..a60757e7a 100644 --- a/libc/string/arc/memcmp.S +++ b/libc/string/arc/memcmp.S @@ -24,14 +24,32 @@ ENTRY(memcmp) ld r4,[r0,0] ld r5,[r1,0] lsr.f lp_count,r3,3 +#ifdef __HS__ + /* In ARCv2 a branch can't be the last instruction in a zero overhead + * loop. + * So we move the branch to the start of the loop, duplicate it + * after the end, and set up r12 so that the branch isn't taken + * initially. + */ + mov_s r12,WORD2 + lpne .Loop_end + brne WORD2,r12,.Lodd + ld WORD2,[r0,4] +#else lpne .Loop_end ld_s WORD2,[r0,4] +#endif ld_s r12,[r1,4] brne r4,r5,.Leven ld.a r4,[r0,8] ld.a r5,[r1,8] +#ifdef __HS__ +.Loop_end: + brne WORD2,r12,.Lodd +#else brne WORD2,r12,.Lodd .Loop_end: +#endif asl_s SHIFT,SHIFT,3 bhs_s .Last_cmp brne r4,r5,.Leven @@ -99,14 +117,25 @@ ENTRY(memcmp) ldb r4,[r0,0] ldb r5,[r1,0] lsr.f lp_count,r3 +#ifdef __HS__ + mov r12,r3 lpne .Lbyte_end + brne r3,r12,.Lbyte_odd +#else + lpne .Lbyte_end +#endif ldb_s r3,[r0,1] ldb r12,[r1,1] brne r4,r5,.Lbyte_even ldb.a r4,[r0,2] ldb.a r5,[r1,2] +#ifdef __HS__ +.Lbyte_end: + brne r3,r12,.Lbyte_odd +#else brne r3,r12,.Lbyte_odd .Lbyte_end: +#endif bcc .Lbyte_even brne r4,r5,.Lbyte_even ldb_s r3,[r0,1] -- cgit v1.2.3