math/mpx-mul4-x86-sse2.S: Additional piece of commentary.

diff --git a/math/mpx-mul4-x86-sse2.S b/math/mpx-mul4-x86-sse2.S
index 5d5714d..5d80860 100644 (file)
--- a/math/mpx-mul4-x86-sse2.S
+++ b/math/mpx-mul4-x86-sse2.S
@@ -550,6 +550,9 @@ INTFUNC(mmla4)
        movd    xmm5, [edi +  4]
        movd    xmm6, [edi +  8]
        movd    xmm7, [edi + 12]
+
+       // Calculate W = U V, and leave it in the destination.  Stash the
+       // carry pieces for later.
        mulacc  [eax +  0], ecx, xmm4, xmm5, xmm6, xmm7
        propout [edi +  0],      xmm4, xmm5