Remove a completed entry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27958 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index a4611b26c0c1d0768bc5ce91b94b70ceadec39b8..2ce31d2224ddabfc114dd0f92c552ff71f66a30f 100644 (file)
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -999,61 +999,6 @@ be able eliminate one of the movaps:
 
 //===---------------------------------------------------------------------===//
 
-Use the 0's in the top part of movss from memory (and from other instructions
-that generate them) to build vectors more efficiently.  Consider:
-
-vector float test(float a) {
- return (vector float){ 0.0, a, 0.0, 0.0}; 
-}
-
-We currently generate this as:
-
-_test:
-        sub %ESP, 28
-        movss %XMM0, DWORD PTR [%ESP + 32]
-        movss DWORD PTR [%ESP + 4], %XMM0
-        mov DWORD PTR [%ESP + 12], 0
-        mov DWORD PTR [%ESP + 8], 0
-        mov DWORD PTR [%ESP], 0
-        movaps %XMM0, XMMWORD PTR [%ESP]
-        add %ESP, 28
-        ret
-
-Something like this should be sufficient:
-
-_test:
-       movss %XMM0, DWORD PTR [%ESP + 4]
-       shufps %XMM0, %XMM0, 81
-       ret
-
-... which takes advantage of the zero elements provided by movss.
-Even xoring a register and shufps'ing IT would be better than the
-above code.
-
-Likewise, for this:
-
-vector float test(float a, float b) {
- return (vector float){ b, a, 0.0, 0.0}; 
-}
-
-_test:
-        pxor %XMM0, %XMM0
-        movss %XMM1, %XMM0
-        movss %XMM2, DWORD PTR [%ESP + 4]
-        unpcklps %XMM2, %XMM1
-        movss %XMM0, DWORD PTR [%ESP + 8]
-        unpcklps %XMM0, %XMM1
-        unpcklps %XMM0, %XMM2
-        ret
-
-... where we do use pxor, it would be better to use the zero'd 
-elements that movss provides to turn this into 2 shufps's instead
-of 3 unpcklps's.
-
-Another example: {0.0, 0.0, a, b }
-
-//===---------------------------------------------------------------------===//
-
 Consider:
 
 __m128 test(float a) {