[llvm] [X86] SimplifyDemandedBitsForTargetNode - add handling for X86ISD::FAND/FOR (PR #136618)

[Simon Pilgrim via llvm-commits]

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@@ -252,28 +252,22 @@ define double @PR136368(double %x) {
 ; SSE-LABEL: PR136368:
 ; SSE:       # %bb.0:
 ; SSE-NEXT:    movapd {{.*#+}} xmm1 = [NaN,NaN]
-; SSE-NEXT:    movapd %xmm0, %xmm2
-; SSE-NEXT:    andpd %xmm1, %xmm2
-; SSE-NEXT:    movsd {{.*#+}} xmm3 = [1.5707963267948966E+0,0.0E+0]
-; SSE-NEXT:    movapd %xmm3, %xmm4
-; SSE-NEXT:    cmpltsd %xmm2, %xmm4
-; SSE-NEXT:    andpd %xmm3, %xmm4
-; SSE-NEXT:    andpd %xmm1, %xmm4
-; SSE-NEXT:    andnpd %xmm0, %xmm1
-; SSE-NEXT:    orpd %xmm4, %xmm1
-; SSE-NEXT:    movapd %xmm1, %xmm0
+; SSE-NEXT:    andpd %xmm0, %xmm1
+; SSE-NEXT:    movsd {{.*#+}} xmm2 = [1.5707963267948966E+0,0.0E+0]
+; SSE-NEXT:    movapd %xmm2, %xmm3
+; SSE-NEXT:    cmpltsd %xmm1, %xmm3
+; SSE-NEXT:    andpd %xmm2, %xmm3
+; SSE-NEXT:    andpd {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0
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RKSimon wrote:

yes - its not a bitselect pattern so canonicalizeBitSelect doesn't match, we just happen to have 0x80...0 and 0x7f...f in codegen.

https://github.com/llvm/llvm-project/pull/136618