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| author | Evan Cheng <evan.cheng@apple.com> | 2008-11-11 17:35:52 +0000 |
|---|---|---|
| committer | Evan Cheng <evan.cheng@apple.com> | 2008-11-11 17:35:52 +0000 |
| commit | 86d77337fcd270bd12ca32674ebab9c8379d56e6 (patch) | |
| tree | 5d4f71c02061ee838365fb151678984c663874fb | |
| parent | 123f4fd42b876842093c702e0804b63e636b3cdd (diff) | |
Add a README entry.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59052 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Target/X86/README.txt | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt index 53c002b282..9274762345 100644 --- a/lib/Target/X86/README.txt +++ b/lib/Target/X86/README.txt @@ -1773,3 +1773,20 @@ gcc 4.3 generates: movl 12(%ebp), %eax popl %ebp ret + +//===---------------------------------------------------------------------===// + +Teach tblgen not to check bitconvert source type in some cases. This allows us +to consolidate the following patterns in X86InstrMMX.td: + +def : Pat<(v2i32 (bitconvert (i64 (vector_extract (v2i64 VR128:$src), + (iPTR 0))))), + (v2i32 (MMX_MOVDQ2Qrr VR128:$src))>; +def : Pat<(v4i16 (bitconvert (i64 (vector_extract (v2i64 VR128:$src), + (iPTR 0))))), + (v4i16 (MMX_MOVDQ2Qrr VR128:$src))>; +def : Pat<(v8i8 (bitconvert (i64 (vector_extract (v2i64 VR128:$src), + (iPTR 0))))), + (v8i8 (MMX_MOVDQ2Qrr VR128:$src))>; + +There are other cases in various td files. |