2.5-18.1

[thirdparty/glibc.git] / sysdeps / alpha / strncmp.S

diff --git a/sysdeps/alpha/strncmp.S b/sysdeps/alpha/strncmp.S
index e2b4ebf857f856b67e6a76f362966656dfa386e5..ff199eb743a3acd3b5c2a7dd6061b37eb886606f 100644 (file)
--- a/sysdeps/alpha/strncmp.S
+++ b/sysdeps/alpha/strncmp.S
@@ -61,8 +61,10 @@ $aligned:
        ornot   t0, t3, t0      # .. e1 :
        cmpbge  zero, t1, t7    # e0    : bits set iff null found
        beq     a2, $eoc        # .. e1 : check end of count
-       subq    a2, 1, a2       # e0    :
+       unop                    # e0    :
        bne     t7, $eos        # .. e1 :
+       unop                    # e0    :
+       beq     t10, $ant_loop  # .. e1 :
 
        /* Aligned compare main loop.
           On entry to this basic block:
@@ -74,13 +76,30 @@ $a_loop:
        bne     t2, $wordcmp    # .. e1 (zdb)
        ldq_u   t1, 8(a1)       # e0    :
        ldq_u   t0, 8(a0)       # .. e1 :
+       subq    a2, 1, a2       # e0    :
+       addq    a1, 8, a1       # .. e1 :
+       addq    a0, 8, a0       # e0    :
+       beq     a2, $eoc        # .. e1 :
+       cmpbge  zero, t1, t7    # e0    :
+       beq     t7, $a_loop     # .. e1 :
+       unop                    # e0    :
+       br      $eos            # .. e1 :
+
+       /* Alternate aligned compare loop, for when there's no trailing
+          bytes on the count.  We have to avoid reading too much data.  */
+$ant_loop:
+       xor     t0, t1, t2      # e0    :
+       bne     t2, $wordcmp    # .. e1 (zdb)
+       subq    a2, 1, a2       # e0    :
+       beq     a2, $zerolength # .. e1 :
+       ldq_u   t1, 8(a1)       # e0    :
+       ldq_u   t0, 8(a0)       # .. e1 :
        addq    a1, 8, a1       # e0    :
        addq    a0, 8, a0       # .. e1 :
        cmpbge  zero, t1, t7    # e0    :
-       beq     a2, $eoc        # .. e1 :
-       subq    a2, 1, a2       # e0    :
-       beq     t7, $a_loop     # .. e1 :
-       br      $eos            # e1    :
+       beq     t7, $ant_loop   # .. e1 :
+       unop                    # e0    :
+       br      $eos            # .. e1 :
 
        /* The two strings are not co-aligned.  Align s1 and cope.  */
 $unaligned:
@@ -184,6 +203,8 @@ $u_final:
 $eoc:
        mskql   t0, t10, t0
        mskql   t1, t10, t1
+       unop
+       cmpbge  zero, t1, t7
 
        /* We've found a zero somewhere in a word we just read.
           On entry to this basic block:
@@ -203,6 +224,7 @@ $eos:
 
        /* Here we have two differing co-aligned words in t0 & t1.
           Bytewise compare them and return (t0 > t1 ? 1 : -1).  */
+       .align 3
 $wordcmp:
        cmpbge  t0, t1, t2      # e0    : comparison yields bit mask of ge
        cmpbge  t1, t0, t3      # .. e1 :
@@ -216,6 +238,7 @@ $wordcmp:
 $done:
        ret                     # e1    :
 
+       .align 3
 $zerolength:
        clr     v0
        ret