Normal quotes

21-05.md

@@ -13,10 +13,10 @@
     ; in length, and length > 0.
 
             sub     eax,eax         ;initialize the checksum
-            shr     ecx,1           ;we’ll do two words per loop
+            shr     ecx,1           ;we'll do two words per loop
             mov     edx,[esi]       ;preload the first dword
             add     esi,4           ;point to the next dword
-            dec     ecx             ;we’ll do 1 checksum outside the loop
+            dec     ecx             ;we'll do 1 checksum outside the loop
             jz      short ckloopend ;only 1 checksum to do
 
     ckloop:
@@ -37,7 +37,7 @@
 
 Listing 21.5 improves upon Listing 21.4 by processing 2 dwords per loop,
 thereby bringing the time per checksummed word down to exactly 1 cycle.
-Listing 21.5 basically does nothing but unroll Listing 21.4’s loop one
+Listing 21.5 basically does nothing but unroll Listing 21.4's loop one
 time, demonstrating that the venerable optimization technique of loop
 unrolling still has some life left in it on the Pentium. The cost for
 this is, as usual, increased code size and complexity, and the use of
@@ -54,7 +54,7 @@ more registers.
     ;  in length, and length > 0.
 
             sub     eax,eax          ;initialize the checksum
-            shr     ecx,2            ;we’ll do two dwords per loop
+            shr     ecx,2            ;we'll do two dwords per loop
             jnc     short noodddword ;is there an odd dword in buffer?
             mov     eax,[esi]        ;checksum the odd dword
             jz      short ckloopdone ;no, done
@@ -62,7 +62,7 @@ more registers.
     noodddword:
             mov     edx,[esi]       ;preload the first dword
             mov     ebx,[esi+4]     ;preload the second dword
-            dec     ecx             ;we’ll do 1 checksum outside the loop
+            dec     ecx             ;we'll do 1 checksum outside the loop
             jz      short ckloopend ;only 1 checksum to do
             add     esi,8           ;point to the next dword
 
@@ -87,30 +87,30 @@ more registers.
             adc     eax,0
 
 Listing 21.5 is undeniably intricate code, and not the sort of thing one
-would choose to write as a matter of course. On the other hand, it’s
+would choose to write as a matter of course. On the other hand, it's
 five times as fast as the tight, seemingly-speedy loop in Listing 21.1
 (and six times as fast as Listing 21.1 would have been if the prefix
-byte had behaved as expected). That’s an awful lot of speed to wring out
+byte had behaved as expected). That's an awful lot of speed to wring out
 of a five-instruction loop, and the TCP/IP checksum is, in fact, used by
 network software, an area in which a five-times speedup might make a
 significant difference in overall system performance.
 
-I don’t claim that Listing 21.5 is the fastest possible way to do a
-TCP/IP checksum on a Pentium; in fact, it isn’t. Unrolling the loop one
-more time, together with a trick of Terje’s that uses **LEA** to advance
+I don't claim that Listing 21.5 is the fastest possible way to do a
+TCP/IP checksum on a Pentium; in fact, it isn't. Unrolling the loop one
+more time, together with a trick of Terje's that uses **LEA** to advance
 ESI (neither **LEA** nor **DEC** affects the carry flag, allowing Terje
 to add the carry from the previous loop iteration into the next
-iteration’s checksum via **ADC**), produces a version that’s a full 33
+iteration's checksum via **ADC**), produces a version that's a full 33
 percent faster. Nonetheless, Listings 21.1 through 21.5 illustrate many
 of the techniques and considerations in Pentium optimization.
-Hand-optimization for the Pentium isn’t simple, and requires careful
+Hand-optimization for the Pentium isn't simple, and requires careful
 measurement to check the efficacy of your optimizations, so reserve it
 for when you really, really need it—but when you need it, you need it
 *bad*.
 
 #### A Quick Note on the 386 and 486 {#Heading8}
 
-I’ve mentioned that Pentium-optimized code does fine on the 486, but not
+I've mentioned that Pentium-optimized code does fine on the 486, but not
 always so well on the 386. On a 486, Listing 21.1 runs at 9 cycles per
 checksummed word, and Listing 21.5 runs at 2.5 cycles per checksummed
 word, a healthy 3.6-times speedup. On a 386, Listing 21.1 runs at 22