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Diffstat (limited to 'lib/Target/X86/README-SSE.txt')
| -rw-r--r-- | lib/Target/X86/README-SSE.txt | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/lib/Target/X86/README-SSE.txt b/lib/Target/X86/README-SSE.txt index d9a03a3..197dae3 100644 --- a/lib/Target/X86/README-SSE.txt +++ b/lib/Target/X86/README-SSE.txt @@ -781,3 +781,14 @@ any number of 0.0 simultaneously. Currently we only use it for simple insertions. See comments in LowerINSERT_VECTOR_ELT_SSE4. + +//===---------------------------------------------------------------------===// + +On a random note, SSE2 should declare insert/extract of 2 x f64 as legal, not +Custom. All combinations of insert/extract reg-reg, reg-mem, and mem-reg are +legal, it'll just take a few extra patterns written in the .td file. + +Note: this is not a code quality issue; the custom lowered code happens to be +right, but we shouldn't have to custom lower anything. This is probably related +to <2 x i64> ops being so bad. + |