[llvm-commits] [llvm] r108096 - /llvm/trunk/lib/Target/X86/README-SSE.txt

Jakob Stoklund Olesen stoklund at 2pi.dk
Sun Jul 11 10:13:42 PDT 2010


Author: stoklund
Date: Sun Jul 11 12:13:42 2010
New Revision: 108096

URL: http://llvm.org/viewvc/llvm-project?rev=108096&view=rev
Log:
Remove obsolete README_SSE note.

We are generating movaps for all XMM register copies, including scalar
floating point values. This is known to be at least as good as movss and movsd
for all known architectures up to and including Nehalem because it avoids a
partial register stall.

The SSEDomainFix pass will switch movaps to movdqa when appropriate (i.e., when
operands come from the integer unit). We don't now that switching movaps to
movapd has any benefit.

The same applies to andps -> pand.

Modified:
    llvm/trunk/lib/Target/X86/README-SSE.txt

Modified: llvm/trunk/lib/Target/X86/README-SSE.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/README-SSE.txt?rev=108096&r1=108095&r2=108096&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/README-SSE.txt (original)
+++ llvm/trunk/lib/Target/X86/README-SSE.txt Sun Jul 11 12:13:42 2010
@@ -89,16 +89,6 @@
 
 //===---------------------------------------------------------------------===//
 
-X86RegisterInfo::copyRegToReg() returns X86::MOVAPSrr for VR128. Is it possible
-to choose between movaps, movapd, and movdqa based on types of source and
-destination?
-
-How about andps, andpd, and pand? Do we really care about the type of the packed
-elements? If not, why not always use the "ps" variants which are likely to be
-shorter.
-
-//===---------------------------------------------------------------------===//
-
 External test Nurbs exposed some problems. Look for
 __ZN15Nurbs_SSE_Cubic17TessellateSurfaceE, bb cond_next140. This is what icc
 emits:





More information about the llvm-commits mailing list