Index: lib/Transform/ScheduleOptimizer.cpp
===================================================================
--- lib/Transform/ScheduleOptimizer.cpp
+++ lib/Transform/ScheduleOptimizer.cpp
@@ -672,12 +672,19 @@
 static bool isMatMulOperandAcc(__isl_keep isl_map *AccMap, int &FirstPos,
                                int &SecondPos) {
   int DimInPos[] = {FirstPos, SecondPos};
-  if (isl_map_foreach_basic_map(AccMap, isMatMulOperandBasicMap,
+  if (isl_map_dim(AccMap, isl_dim_out) != 2)
+    return false;
+  auto *NonPartialAccMap = isl_map_drop_constraints_not_involving_dims(
+      isl_map_copy(AccMap), isl_dim_out, 0, 2);
+  if (isl_map_foreach_basic_map(NonPartialAccMap, isMatMulOperandBasicMap,
                                 static_cast<void *>(DimInPos)) != isl_stat_ok ||
-      DimInPos[0] < 0 || DimInPos[1] < 0)
+      DimInPos[0] < 0 || DimInPos[1] < 0) {
+    isl_map_free(NonPartialAccMap);
     return false;
+  }
   FirstPos = DimInPos[0];
   SecondPos = DimInPos[1];
+  isl_map_free(NonPartialAccMap);
   return true;
 }
 
@@ -694,7 +701,7 @@
 ///                  false, otherwise.
 static bool isMatMulNonScalarReadAccess(MemoryAccess *MemAccess,
                                         MatMulInfoTy &MMI) {
-  if (!MemAccess->isArrayKind() || !MemAccess->isRead())
+  if (!MemAccess->isLatestArrayKind() || !MemAccess->isRead())
     return false;
   isl_map *AccMap = MemAccess->getAccessRelation();
   if (isMatMulOperandAcc(AccMap, MMI.i, MMI.j) && !MMI.ReadFromC &&
@@ -749,15 +756,22 @@
                                  MMI.k, OutDimNum - 1);
   for (auto *MemA = Stmt->begin(); MemA != Stmt->end() - 1; MemA++) {
     auto *MemAccessPtr = *MemA;
-    if (MemAccessPtr->isArrayKind() && MemAccessPtr != MMI.WriteToC &&
+    if (MemAccessPtr->isLatestArrayKind() &&
         !isMatMulNonScalarReadAccess(MemAccessPtr, MMI) &&
         !(MemAccessPtr->isStrideZero(isl_map_copy(MapI)) &&
           MemAccessPtr->isStrideZero(isl_map_copy(MapJ)) &&
           MemAccessPtr->isStrideZero(isl_map_copy(MapK)))) {
-      isl_map_free(MapI);
-      isl_map_free(MapJ);
-      isl_map_free(MapK);
-      return false;
+      auto *AccessIntersection =
+          isl_map_intersect(MemAccessPtr->getLatestAccessRelation(),
+                            MMI.WriteToC->getLatestAccessRelation());
+      if (isl_map_is_empty(AccessIntersection)) {
+        isl_map_free(AccessIntersection);
+        isl_map_free(MapI);
+        isl_map_free(MapJ);
+        isl_map_free(MapK);
+        return false;
+      }
+      isl_map_free(AccessIntersection);
     }
   }
   isl_map_free(MapI);
@@ -841,7 +855,7 @@
     return false;
   for (auto *MemA = Stmt->end() - 1; MemA != Stmt->begin(); MemA--) {
     auto *MemAccessPtr = *MemA;
-    if (!MemAccessPtr->isArrayKind())
+    if (!MemAccessPtr->isLatestArrayKind())
       continue;
     if (!MemAccessPtr->isWrite())
       return false;
Index: test/ScheduleOptimizer/pattern-matching-based-opts_11.ll
===================================================================
--- /dev/null
+++ test/ScheduleOptimizer/pattern-matching-based-opts_11.ll
@@ -0,0 +1,54 @@
+; RUN: opt %loadPolly -polly -polly-delicm \
+; RUN: -polly-delicm-overapproximate-writes -polly-pattern-matching-based-opts \
+; RUN: -polly-opt-isl -debug  < %s 2>&1 | FileCheck %s
+;
+; Check that the pattern matching detects the matrix multiplication pattern
+; in case memory accesses were modified by DeLICM.
+;
+; CHECK: The matrix multiplication pattern was detected
+;
+
+define internal fastcc void @kernel_gemm([1024 x double]* nocapture %C, [1024 x double]* nocapture readonly %A, [1024 x double]* nocapture readonly %B) unnamed_addr {
+entry:
+  br label %entry.split
+
+entry.split:                                      ; preds = %entry
+  br label %for.cond1.preheader
+
+for.cond1.preheader:                              ; preds = %for.inc20, %entry.split
+  %indvars.iv7 = phi i64 [ 0, %entry.split ], [ %indvars.iv.next8, %for.inc20 ]
+  br label %for.cond4.preheader
+
+for.cond4.preheader:                              ; preds = %for.inc17, %for.cond1.preheader
+  %indvars.iv4 = phi i64 [ 0, %for.cond1.preheader ], [ %indvars.iv.next5, %for.inc17 ]
+  %arrayidx16 = getelementptr inbounds [1024 x double], [1024 x double]* %C, i64 %indvars.iv7, i64 %indvars.iv4
+  %.pre = load double, double* %arrayidx16, align 8
+  br label %for.body6
+
+for.body6:                                        ; preds = %for.body6, %for.cond4.preheader
+  %0 = phi double [ %.pre, %for.cond4.preheader ], [ %add, %for.body6 ]
+  %indvars.iv = phi i64 [ 0, %for.cond4.preheader ], [ %indvars.iv.next, %for.body6 ]
+  %arrayidx8 = getelementptr inbounds [1024 x double], [1024 x double]* %A, i64 %indvars.iv7, i64 %indvars.iv
+  %1 = load double, double* %arrayidx8, align 8
+  %arrayidx12 = getelementptr inbounds [1024 x double], [1024 x double]* %B, i64 %indvars.iv, i64 %indvars.iv4
+  %2 = load double, double* %arrayidx12, align 8
+  %mul = fmul double %1, %2
+  %add = fadd double %0, %mul
+  store double %add, double* %arrayidx16, align 8
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 1024
+  br i1 %exitcond, label %for.inc17, label %for.body6
+
+for.inc17:                                        ; preds = %for.body6
+  %indvars.iv.next5 = add nuw nsw i64 %indvars.iv4, 1
+  %exitcond6 = icmp eq i64 %indvars.iv.next5, 1024
+  br i1 %exitcond6, label %for.inc20, label %for.cond4.preheader
+
+for.inc20:                                        ; preds = %for.inc17
+  %indvars.iv.next8 = add nuw nsw i64 %indvars.iv7, 1
+  %exitcond9 = icmp eq i64 %indvars.iv.next8, 1024
+  br i1 %exitcond9, label %for.end22, label %for.cond1.preheader
+
+for.end22:                                        ; preds = %for.inc20
+  ret void
+}