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--- mysql/strings/longlong2str-x86.s 2005-07-15 14:06:49.000000000 +0200
+++ mysql-fixed/strings/longlong2str-x86.s 2005-07-15 14:07:42.000000000 +0200
@@ -13,8 +13,9 @@
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-# Optimized longlong2str function for Intel 80x86 (gcc/gas syntax)
-# Some set sequences are optimized for pentuimpro II
+# longlong2str function for Intel 80x86 (gcc/gas syntax)
+
+# See longlong2str(dst,radix,val) description in longlong2str.c.
.file "longlong2str.s"
.version "1.01"
@@ -24,99 +25,88 @@
.globl longlong2str
.type longlong2str,@function
-
+
longlong2str:
- subl $80,%esp
+ subl $80,%esp # Temporary buffer for up to 64 radix-2 digits
pushl %ebp
pushl %esi
pushl %edi
pushl %ebx
- movl 100(%esp),%esi # Lower part of val
- movl 104(%esp),%ebp # Higher part of val
- movl 108(%esp),%edi # get dst
- movl 112(%esp),%ebx # Radix
- movl %ebx,%eax
- testl %eax,%eax
- jge .L144
-
- addl $36,%eax
- cmpl $34,%eax
- ja .Lerror # Wrong radix
+
+ movl 100(%esp),%esi # esi = Lower part of val
+ movl 112(%esp),%ebx # ebx = Radix
+ movl 104(%esp),%ebp # ebp = Higher part of val
+ movl 108(%esp),%edi # edi -> dst
+
+ testl %ebx,%ebx
+ jge .L144 # (Radix >= 0)
+
testl %ebp,%ebp
- jge .L146
- movb $45,(%edi) # Add sign
- incl %edi # Change sign of val
- negl %esi
- adcl $0,%ebp
- negl %ebp
+ jge .L146 # (Higher part of val >= 0)
+ movb $45,(%edi) # Add '-' sign
+ incl %edi
+ negl %esi # Change val to positive
+ adcl $0,%ebp
+ negl %ebp
.L146:
- negl %ebx # Change radix to positive
- jmp .L148
- .align 4
+ negl %ebx # Change radix to positive
.L144:
- addl $-2,%eax
- cmpl $34,%eax
- ja .Lerror # Radix in range
-
-.L148:
- movl %esi,%eax # Test if zero (for easy loop)
- orl %ebp,%eax
- jne .L150
- movb $48,(%edi)
- incl %edi
- jmp .L10_end
- .align 4
-
-.L150:
- leal 92(%esp),%ecx # End of buffer
- jmp .L155
- .align 4
+ cmpl $36,%ebx # Radix must be between 2 and 36
+ ja .Lerror # (Radix not in range)
+ cmpl $2,%ebx
+ jb .Lerror # (Radix not in range)
+
+ movl %esi,%eax # eax = lower part of val ...
+ orl %ebp,%eax # and it stays thus if ebp=0
+ je Lzero # (Treat zero as special case)
-.L153:
- # val is stored in in ebp:esi
-
- movl %ebp,%eax # High part of value
- xorl %edx,%edx
- divl %ebx
- movl %eax,%ebp
- movl %esi,%eax
- divl %ebx
- decl %ecx
- movl %eax,%esi # quotent in ebp:esi
- movb _dig_vec_upper(%edx),%al # al is faster than dl
- movb %al,(%ecx) # store value in buff
- .align 4
-.L155:
+ leal 92(%esp),%ecx # ecx -> End of temporary buffer
+
testl %ebp,%ebp
- ja .L153
- testl %esi,%esi # rest value
- jl .L153
- je .L10_mov # Ready
- movl %esi,%eax
- movl $_dig_vec_upper,%ebp
- .align 4
-
-.L154: # Do rest with integer precision
- cltd
- divl %ebx
- decl %ecx
- movb (%edx,%ebp),%dl # bh is always zero as ebx=radix < 36
- testl %eax,%eax
- movb %dl,(%ecx)
- jne .L154
-
-.L10_mov:
- movl %ecx,%esi
- leal 92(%esp),%ecx # End of buffer
- subl %esi,%ecx
- rep
- movsb
-
-.L10_end:
- movl %edi,%eax # Pointer to end null
- movb $0,(%edi) # Store the end null
-
-.L165:
+ je Llow # (Higher part of val = 0)
+
+Lhigh:
+ #val in ebp:esi. div the high part by the radix,
+ #then div remainder + low part by the radix.
+ movl %ebp,%eax # edx=0,eax=high(from ebp)
+ xorl %edx,%edx
+ decl %ecx
+ divl %ebx
+ movl %eax,%ebp # edx=result of last, eax=low(from esi)
+ movl %esi,%eax
+ divl %ebx
+ movl %eax,%esi # ebp:esi = quotient
+ movb %dl,(%ecx) # store byte in temporary buffer
+ testl %ebp,%ebp
+ jne Lhigh # (Higher part of val still > 0)
+
+Llow:
+ #val in 0:eax. div 0 + low part by the radix.
+ xorl %edx,%edx
+ decl %ecx
+ divl %ebx
+ movb %dl,(%ecx) # store byte in temporary buffer
+ testl %eax,%eax
+ jne Llow # (Lower part of val still <> 0)
+
+ leal 92(%esp),%esi # esi -> End of temporary buffer
+
+Lmov:
+ movb (%ecx),%dl # dl = byte from temporary buffer
+ movb $-1,%bl
+ cmpb $10,%dl # add 7 if dl > '9'
+ adcb $0,%bl
+ addb $48,%dl # add '0'
+ andb $7,%bl
+ addb %bl,%dl
+ incl %ecx
+ movb %dl,(%edi) # put dl in dst
+ incl %edi
+ cmpl %ecx,%esi
+ ja Lmov # (more bytes exist in temporary buffer)
+ movb $0,(%edi) # trailing '\0' in dst
+ movl %edi,%eax # eax = return value = pointer to '\0'
+.Lret:
popl %ebx
popl %edi
popl %esi
@@ -126,20 +116,28 @@
.Lerror:
xorl %eax,%eax # Wrong radix
- jmp .L165
+ jmp .Lret
-.Lfe3:
- .size longlong2str,.Lfe3-longlong2str
+Lzero:
+ # Treat 0 as a special case. Unnecessary but we
+ # expect 0 will be frequent.
+ movl 108(%esp),%eax # eax = dst
+ popl %ebx
+ movb $48,(%eax) # '0'
+ popl %edi
+ incl %eax
+ popl %esi
+ addl $80,%esp
+ movb $0,(%eax) # '\0'
+ popl %ebp
+ ret
#
# This is almost equal to the above, except that we can do the final
# loop much more efficient
-#
+#
.align 4
-.Ltmp:
- .long 0xcccccccd
- .align 4
.globl longlong10_to_str
.type longlong10_to_str,@function
@@ -202,7 +200,7 @@
# The following code uses some tricks to change division by 10 to
# multiplication and shifts
- movl .Ltmp,%esi # set %esi to 0xcccccccd
+ movl $0xcccccccd,%esi # set %esi to 0xcccccccd
.L10_40:
movl %ebx,%eax
@@ -217,7 +215,27 @@
movl %edx,%ebx
testl %ebx,%ebx
jne .L10_40
- jmp .L10_mov # Shared end with longlong10_to_str
+# jmp .L10_mov # Shared end with longlong10_to_str
+
+.L10_mov:
+ movl %ecx,%esi
+ leal 92(%esp),%ecx # End of buffer
+ subl %esi,%ecx
+ rep
+ movsb
+
+.L10_end:
+ movl %edi,%eax # Pointer to end null
+ movb $0,(%edi) # Store the end null
+
+.L165:
+ popl %ebx
+ popl %edi
+ popl %esi
+ popl %ebp
+ addl $80,%esp
+ ret
+
.L10end:
.size longlong10_to_str,.L10end-longlong10_to_str
|
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