[llvm] 379c5b3 - [X86][SSE] combineVectorSizedSetCCEquality - remove unused AVX2 MOVMSK path. NFCI.

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2020-06-16T10:07:41+01:00
New Revision: 379c5b31f7a5d5ef2d45c0e1203dc966cd3e52f6

URL: https://github.com/llvm/llvm-project/commit/379c5b31f7a5d5ef2d45c0e1203dc966cd3e52f6
DIFF: https://github.com/llvm/llvm-project/commit/379c5b31f7a5d5ef2d45c0e1203dc966cd3e52f6.diff

LOG: [X86][SSE] combineVectorSizedSetCCEquality - remove unused AVX2 MOVMSK path. NFCI.

If PTEST is not available, then we're guaranteed to be performing a 128-bit vector comparison using MOVMSK(PCMPEQB(v16i8)).

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86ISelLowering.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index e11f10ab4b87..d41301b12b1e 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -45940,11 +45940,10 @@ static SDValue combineVectorSizedSetCCEquality(SDNode *SetCC, SelectionDAG &DAG,
     // If all bytes match (bitmask is 0x(FFFF)FFFF), that's equality.
     // setcc i128 X, Y, eq --> setcc (pmovmskb (pcmpeqb X, Y)), 0xFFFF, eq
     // setcc i128 X, Y, ne --> setcc (pmovmskb (pcmpeqb X, Y)), 0xFFFF, ne
-    // setcc i256 X, Y, eq --> setcc (vpmovmskb (vpcmpeqb X, Y)), 0xFFFFFFFF, eq
-    // setcc i256 X, Y, ne --> setcc (vpmovmskb (vpcmpeqb X, Y)), 0xFFFFFFFF, ne
+    assert(Cmp.getValueType() == MVT::v16i8 &&
+           "Non 128-bit vector on pre-SSE41 target");
     SDValue MovMsk = DAG.getNode(X86ISD::MOVMSK, DL, MVT::i32, Cmp);
-    SDValue FFFFs = DAG.getConstant(OpSize == 128 ? 0xFFFF : 0xFFFFFFFF, DL,
-                                    MVT::i32);
+    SDValue FFFFs = DAG.getConstant(0xFFFF, DL, MVT::i32);
     return DAG.getSetCC(DL, VT, MovMsk, FFFFs, CC);
   }