diff options
| author | Nate Begeman <natebegeman@mac.com> | 2006-03-26 19:19:27 +0000 |
|---|---|---|
| committer | Nate Begeman <natebegeman@mac.com> | 2006-03-26 19:19:27 +0000 |
| commit | c02e5a8668b53ea36935000d964723b275df3a75 (patch) | |
| tree | b8dd3c09754b1a04e3b55904f8dee39b41c5d71e | |
| parent | 6d92caddc4aa5fc946b294259e00cc35536e61e8 (diff) | |
Readme note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27152 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Target/X86/README.txt | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt index 91bdb538e9..58a864e01c 100644 --- a/lib/Target/X86/README.txt +++ b/lib/Target/X86/README.txt @@ -542,6 +542,13 @@ Currently the load folding imull has a higher complexity than the LEA32 pattern. //===---------------------------------------------------------------------===// +We are currently lowering large (1MB+) memmove/memcpy to rep/stosl and rep/movsl +We should leave these as libcalls for everything over a much lower threshold, +since libc is hand tuned for medium and large mem ops (avoiding RFO for large +stores, TLB preheating, etc) + +//===---------------------------------------------------------------------===// + Lower memcpy / memset to a series of SSE 128 bit move instructions when it's feasible. |