X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FREADME.txt;h=7e9888cc13e80b48466cb5cca8997819eb07cb92;hb=6902c8db2603287335a7e46257b4530674983116;hp=52a334a6174919efab97fbcc18b2287e68a845cd;hpb=fd48a80e144fdca6e5c7e6091942f70c2ea4ea8f;p=oota-llvm.git diff --git a/lib/Target/README.txt b/lib/Target/README.txt index 52a334a6174..7e9888cc13e 100644 --- a/lib/Target/README.txt +++ b/lib/Target/README.txt @@ -106,7 +106,7 @@ for 1,2,4,8 bytes. //===---------------------------------------------------------------------===// It would be nice to revert this patch: -http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20060213/031986.html +http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20060213/031986.html And teach the dag combiner enough to simplify the code expanded before legalize. It seems plausible that this knowledge would let it simplify other @@ -1844,44 +1844,6 @@ we remove checking in code like //===---------------------------------------------------------------------===// -This code (from Benchmarks/Dhrystone/dry.c): - -define i32 @Func1(i32, i32) nounwind readnone optsize ssp { -entry: - %sext = shl i32 %0, 24 - %conv = ashr i32 %sext, 24 - %sext6 = shl i32 %1, 24 - %conv4 = ashr i32 %sext6, 24 - %cmp = icmp eq i32 %conv, %conv4 - %. = select i1 %cmp, i32 10000, i32 0 - ret i32 %. -} - -Should be simplified into something like: - -define i32 @Func1(i32, i32) nounwind readnone optsize ssp { -entry: - %sext = shl i32 %0, 24 - %conv = and i32 %sext, 0xFF000000 - %sext6 = shl i32 %1, 24 - %conv4 = and i32 %sext6, 0xFF000000 - %cmp = icmp eq i32 %conv, %conv4 - %. = select i1 %cmp, i32 10000, i32 0 - ret i32 %. -} - -and then to: - -define i32 @Func1(i32, i32) nounwind readnone optsize ssp { -entry: - %conv = and i32 %0, 0xFF - %conv4 = and i32 %1, 0xFF - %cmp = icmp eq i32 %conv, %conv4 - %. = select i1 %cmp, i32 10000, i32 0 - ret i32 %. -} -//===---------------------------------------------------------------------===// - clang -O3 currently compiles this code int g(unsigned int a) {