From 9d071cbb92e2f28be2067fdb5cf21b396e34838d Mon Sep 17 00:00:00 2001 From: Benjamin Kramer Date: Thu, 23 Dec 2010 15:32:07 +0000 Subject: [PATCH] Remove/fix invalid README entries. The well thought out strcpy function doesn't return a pointer to the end of the string. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122496 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/README.txt | 23 ++--------------------- 1 file changed, 2 insertions(+), 21 deletions(-) diff --git a/lib/Target/README.txt b/lib/Target/README.txt index abb8ee6f499..c9561660b1c 100644 --- a/lib/Target/README.txt +++ b/lib/Target/README.txt @@ -697,7 +697,7 @@ implementations of ceil/floor/rint. 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 @@ Those should be turned into a switch. 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 @@ This pattern repeats several times, basically doing: //===---------------------------------------------------------------------===// -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-@pgn_event, which means 1910=1908. - -//===---------------------------------------------------------------------===// - 186.crafty has this interesting pattern with the "out.4543" variable: call void @llvm.memcpy.i32(