A couple minor README updates.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91823 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 9b7aab801eb6c45bc2a914d14e8a693ed9fdfe65..afd9f53ea6bbc2d280a1d1826fd69967221b7bcb 100644 (file)
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -123,20 +123,6 @@ when it can invert the result of the compare for free.
 
 //===---------------------------------------------------------------------===//
 
-How about intrinsics? An example is:
-  *res = _mm_mulhi_epu16(*A, _mm_mul_epu32(*B, *C));
-
-compiles to
-       pmuludq (%eax), %xmm0
-       movl 8(%esp), %eax
-       movdqa (%eax), %xmm1
-       pmulhuw %xmm0, %xmm1
-
-The transformation probably requires a X86 specific pass or a DAG combiner
-target specific hook.
-
-//===---------------------------------------------------------------------===//
-
 In many cases, LLVM generates code like this:
 
 _test:
@@ -1762,6 +1748,11 @@ LBB1_1:  ## bb1
        cmpl    $150, %edi
        jne     LBB1_1  ## bb1
 
+The issue is that we hoist the cast of "scaler" to long long outside of the
+loop, the value comes into the loop as two values, and
+RegsForValue::getCopyFromRegs doesn't know how to put an AssertSext on the
+constructed BUILD_PAIR which represents the cast value.
+
 //===---------------------------------------------------------------------===//
 
 Test instructions can be eliminated by using EFLAGS values from arithmetic