Fix for #1767.

llvm_patches/10_0_Fix_For_1767.patch

@@ -0,0 +1,79 @@
+# This patch is required to fix the crash referenced to in #1767.
+# It is a port of the following llvm 11.0 commit : https://reviews.llvm.org/D76994.
+diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
+index 63ddb59fce6..822da218326 100644
+--- lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
++++ lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
+@@ -173,7 +173,7 @@ void DAGTypeLegalizer::PerformExpensiveChecks() {
+       }
+     }
+   }
+-
++#ifndef NDEBUG
+   // Checked that NewNodes are only used by other NewNodes.
+   for (unsigned i = 0, e = NewNodes.size(); i != e; ++i) {
+     SDNode *N = NewNodes[i];
+@@ -181,6 +181,7 @@ void DAGTypeLegalizer::PerformExpensiveChecks() {
+          UI != UE; ++UI)
+       assert(UI->getNodeId() == NewNode && "NewNode used by non-NewNode!");
+   }
++#endif
+ }
+
+ /// This is the main entry point for the type legalizer. This does a top-down
+diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
+index faae14444d5..b908c5c58e9 100644
+--- lib/CodeGen/SelectionDAG/LegalizeTypes.h
++++ lib/CodeGen/SelectionDAG/LegalizeTypes.h
+@@ -155,7 +155,9 @@ private:
+   const SDValue &getSDValue(TableId &Id) {
+     RemapId(Id);
+     assert(Id && "TableId should be non-zero");
+-    return IdToValueMap[Id];
++    auto I = IdToValueMap.find(Id);
++    assert(I != IdToValueMap.end() && "cannot find Id in map");
++    return I->second;
+   }
+
+ public:
+@@ -172,24 +174,29 @@ public:
+   bool run();
+
+   void NoteDeletion(SDNode *Old, SDNode *New) {
++    assert(Old != New && "node replaced with self");
+     for (unsigned i = 0, e = Old->getNumValues(); i != e; ++i) {
+       TableId NewId = getTableId(SDValue(New, i));
+       TableId OldId = getTableId(SDValue(Old, i));
+
+-      if (OldId != NewId)
++      if (OldId != NewId) {
+         ReplacedValues[OldId] = NewId;
+
+-      // Delete Node from tables.
++        // Delete Node from tables.  We cannot do this when OldId == NewId,
++        // because NewId can still have table references to it in
++        // ReplacedValues.
++        IdToValueMap.erase(OldId);
++        PromotedIntegers.erase(OldId);
++        ExpandedIntegers.erase(OldId);
++        SoftenedFloats.erase(OldId);
++        PromotedFloats.erase(OldId);
++        ExpandedFloats.erase(OldId);
++        ScalarizedVectors.erase(OldId);
++        SplitVectors.erase(OldId);
++        WidenedVectors.erase(OldId);
++      }
++
+       ValueToIdMap.erase(SDValue(Old, i));
+-      IdToValueMap.erase(OldId);
+-      PromotedIntegers.erase(OldId);
+-      ExpandedIntegers.erase(OldId);
+-      SoftenedFloats.erase(OldId);
+-      PromotedFloats.erase(OldId);
+-      ExpandedFloats.erase(OldId);
+-      ScalarizedVectors.erase(OldId);
+-      SplitVectors.erase(OldId);
+-      WidenedVectors.erase(OldId);
+     }
+   }
+

tests/lit-tests/1767.ispc

@@ -0,0 +1,7 @@
+// RUN: %{ispc} --target=avx2-i32x16 %s -o %t.o
+// REQUIRES: X86_ENABLED
+extern uniform bool arr_4[17];
+export void test(uniform int64 var_1, uniform bool var_15) {
+    foreach (i_0 = var_1... 16U)
+        arr_4[i_0] = !(varying bool)reduce_min(180) ? 5923697687793782713ULL : (varying bool)var_15;
+}