From 0e4bd393652f1664cc3e46dc2272a18c48ab7566 Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper@intel.com>
Date: Wed, 6 Dec 2017 00:15:17 +0000
Subject: [PATCH] [X86] Update to getSetCCResultType to be more robust to EVT
 types.

Attempt to determine what the type will be legalized to and then analyze that to see if we will be able to use a vXi1 compare.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319861 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/X86ISelLowering.cpp | 45 ++++++++++++++------------------------
 1 file changed, 17 insertions(+), 28 deletions(-)

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 5f013753ea8..e8655f99c6d 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1716,37 +1716,26 @@ EVT X86TargetLowering::getSetCCResultType(const DataLayout &DL,
   if (!VT.isVector())
     return MVT::i8;
 
-  if (VT.getSizeInBits() >= 512) {
-    EVT EltVT = VT.getVectorElementType();
+  if (Subtarget.hasAVX512()) {
     const unsigned NumElts = VT.getVectorNumElements();
-    if (Subtarget.hasAVX512())
-      if (EltVT == MVT::i32 || EltVT == MVT::i64 ||
-          EltVT == MVT::f32 || EltVT == MVT::f64)
-        return EVT::getVectorVT(Context, MVT::i1, NumElts);
-    if (Subtarget.hasBWI())
-      if (EltVT == MVT::i8 || EltVT == MVT::i16)
-        return EVT::getVectorVT(Context, MVT::i1, NumElts);
-  }
 
-  if (VT.isSimple()) {
-    MVT VVT = VT.getSimpleVT();
-    const unsigned NumElts = VVT.getVectorNumElements();
-    MVT EltVT = VVT.getVectorElementType();
-
-    if (Subtarget.hasBWI() && Subtarget.hasVLX())
-      return MVT::getVectorVT(MVT::i1, NumElts);
-
-    if (!isTypeLegal(VT) && getTypeAction(Context, VT) == TypePromoteInteger) {
-      EVT LegalVT = getTypeToTransformTo(Context, VT);
-      EltVT = LegalVT.getVectorElementType().getSimpleVT();
+    // Figure out what this type will be legalized to.
+    EVT LegalVT = VT;
+    while (getTypeAction(Context, LegalVT) != TypeLegal)
+      LegalVT = getTypeToTransformTo(Context, LegalVT);
+
+    // If we got a 512-bit vector then we'll definitely have a vXi1 compare.
+    if (LegalVT.getSimpleVT().is512BitVector())
+      return EVT::getVectorVT(Context, MVT::i1, NumElts);
+
+    if (LegalVT.getSimpleVT().isVector() && Subtarget.hasVLX()) {
+      // If we legalized to less than a 512-bit vector, then we will use a vXi1
+      // compare for vXi32/vXi64 for sure. If we have BWI we will also support
+      // vXi16/vXi8.
+      MVT EltVT = LegalVT.getSimpleVT().getVectorElementType();
+      if (Subtarget.hasBWI() || EltVT.getSizeInBits() >= 32)
+        return EVT::getVectorVT(Context, MVT::i1, NumElts);
     }
-
-    if (Subtarget.hasVLX() && EltVT.getSizeInBits() >= 32)
-      switch(NumElts) {
-      case 2: return MVT::v2i1;
-      case 4: return MVT::v4i1;
-      case 8: return MVT::v8i1;
-      }
   }
 
   return VT.changeVectorElementTypeToInteger();
-- 
2.11.0