[llvm-commits] [llvm] r122496 - /llvm/trunk/lib/Target/README.txt

[Benjamin Kramer]

Author: d0k
Date: Thu Dec 23 09:32:07 2010
New Revision: 122496

URL: http://llvm.org/viewvc/llvm-project?rev=122496&view=rev
Log:
Remove/fix invalid README entries. The well thought out strcpy function doesn't return a pointer to the end of the string.

Modified:
    llvm/trunk/lib/Target/README.txt

Modified: llvm/trunk/lib/Target/README.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/README.txt?rev=122496&r1=122495&r2=122496&view=diff
==============================================================================
--- llvm/trunk/lib/Target/README.txt (original)
+++ llvm/trunk/lib/Target/README.txt Thu Dec 23 09:32:07 2010
@@ -697,7 +697,7 @@
 Consider:
 
 int test() {
-  long long input[8] = {1,1,1,1,1,1,1,1};
+  long long input[8] = {1,0,1,0,1,0,1,0};
   foo(input);
 }
 
@@ -1432,14 +1432,7 @@
         
 This is interesting for a couple reasons.  First, in this:
 
-        %3073 = call i8* @strcpy(i8* %3072, i8* %3071) nounwind
-        %strlen = call i32 @strlen(i8* %3072)  
-
-The strlen could be replaced with: %strlen = sub %3072, %3073, because the
-strcpy call returns a pointer to the end of the string.  Based on that, the
-endptr GEP just becomes equal to 3073, which eliminates a strlen call and GEP.
-
-Second, the memcpy+strlen strlen can be replaced with:
+The memcpy+strlen strlen can be replaced with:
 
         %3074 = call i32 @strlen([5 x i8]* @"\01LC42") nounwind readonly 
 
@@ -1515,18 +1508,6 @@
 
 //===---------------------------------------------------------------------===//
 
-186.crafty also contains this code:
-
-%1906 = call i32 @strlen(i8* getelementptr ([32 x i8]* @pgn_event, i32 0,i32 0))
-%1907 = getelementptr [32 x i8]* @pgn_event, i32 0, i32 %1906
-%1908 = call i8* @strcpy(i8* %1907, i8* %1905) nounwind align 1
-%1909 = call i32 @strlen(i8* getelementptr ([32 x i8]* @pgn_event, i32 0,i32 0))
-%1910 = getelementptr [32 x i8]* @pgn_event, i32 0, i32 %1909         
-
-The last strlen is computable as 1908- at pgn_event, which means 1910=1908.
-
-//===---------------------------------------------------------------------===//
-
 186.crafty has this interesting pattern with the "out.4543" variable:
 
 call void @llvm.memcpy.i32(