Index: llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombine.cpp
===================================================================
--- llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombine.cpp
+++ llvm/lib/Transforms/AggressiveInstCombine/AggressiveInstCombine.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/AssumptionCache.h"
 #include "llvm/Analysis/BasicAliasAnalysis.h"
+#include "llvm/Analysis/ConstantFolding.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/LogicCombine.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
@@ -852,6 +853,88 @@
   return MadeChange;
 }
 
+// Return a minimum gep stride, greatest common divisor of consective gep
+// indices type sizes (c.f. Bézout's identity). Currently ignore the indices
+// constantness and struct type.
+uint64_t GetMinimumGEPStride(Value *PtrOp, const DataLayout DL) {
+
+  if (auto GEP = dyn_cast<GEPOperator>(PtrOp)) {
+    uint64_t g;
+    auto Euc = [](uint64_t a, uint64_t b) {
+      if (a < b) {
+        uint64_t t = a;
+        a = b;
+        b = t;
+      }
+      while (b != 0) {
+        uint64_t r = a % b;
+        a = b;
+        b = r;
+      }
+      return a;
+    };
+    g = DL.getTypeStoreSize(GEP->getSourceElementType());
+    Value *V = GEP;
+    while (auto GEP = dyn_cast<GEPOperator>(V)) {
+      g = Euc(g, DL.getTypeStoreSize(GEP->getResultElementType()));
+      V = GEP->getPointerOperand();
+    }
+    return g;
+  }
+
+  return 1;
+}
+
+/// If C is a constant patterned array and all valid loaded results for given
+/// alignment are same to a constant, return that constant.
+static bool foldPatternedLoads(Instruction &I, const DataLayout &DL) {
+
+  auto *LI = dyn_cast<LoadInst>(&I);
+  if (!LI)
+    return false;
+
+  auto *PtrOp = LI->getOperand(0);
+  auto *GV = dyn_cast<GlobalVariable>(getUnderlyingObject(PtrOp));
+  if (!GV || !GV->isConstant() ||
+      (!GV->hasDefinitiveInitializer() && !GV->hasUniqueInitializer()))
+    return false;
+
+  uint64_t LoadAlign = LI->getAlign().value();
+  if (LoadAlign > GV->getAlign().valueOrOne().value())
+    return false;
+  Constant *C = GV->getInitializer();
+  Type *LoadTy = LI->getType();
+
+  unsigned GVSize = DL.getTypeStoreSize(C->getType());
+
+  // Bail for large initializers in excess of 64K to avoid allocating
+  // too much memory.
+  if (!GVSize || UINT16_MAX < GVSize)
+    return false;
+
+  unsigned LoadSize = LoadTy->getScalarSizeInBits() / 8;
+  const APInt Offset(DL.getTypeSizeInBits(C->getType()), 0);
+  Constant *Ca = ConstantFoldLoadFromConst(
+      C, LoadTy, APInt(DL.getTypeSizeInBits(C->getType()), 0), DL);
+
+  // Any possible offset could be multiple of minimum GEP stride. And any valid
+  // offset is multiple of load alignment, so checking onle multiples of bigger
+  // one is sufficient to say results' equality.
+  uint64_t Stride = GetMinimumGEPStride(PtrOp, DL);
+  Stride = Stride < LoadAlign ? LoadAlign : Stride;
+
+  for (uint64_t ByteOffset = Stride, E = GVSize - LoadSize; ByteOffset <= E;
+       ByteOffset += Stride)
+    if (Ca != ConstantFoldLoadFromConst(
+                  C, LoadTy,
+                  APInt(DL.getTypeSizeInBits(C->getType()), ByteOffset), DL))
+      return false;
+  I.replaceAllUsesWith(Ca);
+
+  return true;
+}
+
+
 /// This is the entry point for folds that could be implemented in regular
 /// InstCombine, but they are separated because they are not expected to
 /// occur frequently and/or have more than a constant-length pattern match.
@@ -878,6 +961,7 @@
       MadeChange |= tryToFPToSat(I, TTI);
       MadeChange |= tryToRecognizeTableBasedCttz(I);
       MadeChange |= foldConsecutiveLoads(I, DL, TTI, AA);
+      MadeChange |= foldPatternedLoads(I, DL);
       // NOTE: This function introduces erasing of the instruction `I`, so it
       // needs to be called at the end of this sequence, otherwise we may make
       // bugs.
Index: llvm/test/Transforms/AggressiveInstCombine/patterned-load.ll
===================================================================
--- llvm/test/Transforms/AggressiveInstCombine/patterned-load.ll
+++ llvm/test/Transforms/AggressiveInstCombine/patterned-load.ll
@@ -7,9 +7,7 @@
 
 define i8 @gep_load_i8_align2(i64 %idx){
 ; CHECK-LABEL: @gep_load_i8_align2(
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i8, ptr @constarray, i64 [[IDX:%.*]]
-; CHECK-NEXT:    [[TMP2:%.*]] = load i8, ptr [[TMP1]], align 2
-; CHECK-NEXT:    ret i8 [[TMP2]]
+; CHECK-NEXT:    ret i8 1
 ;
   %1 = getelementptr inbounds i8, ptr @constarray, i64 %idx
   %2 = load i8, ptr %1, align 2
@@ -29,10 +27,11 @@
 }
 
 define i32 @gep_i32_load_i32_align4(i64 %idx){
-; CHECK-LABEL: @gep_i32_load_i32_align4(
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, ptr @constarray, i64 [[IDX:%.*]]
-; CHECK-NEXT:    [[TMP2:%.*]] = load i32, ptr [[TMP1]], align 4
-; CHECK-NEXT:    ret i32 [[TMP2]]
+; LE-LABEL: @gep_i32_load_i32_align4(
+; LE-NEXT:    ret i32 65537
+;
+; BE-LABEL: @gep_i32_load_i32_align4(
+; BE-NEXT:    ret i32 16777472
 ;
   %1 = getelementptr inbounds i32, ptr @constarray, i64 %idx
   %2 = load i32, ptr %1, align 4
@@ -40,10 +39,11 @@
 }
 
 define i32 @gep_i32_load_i32_align4_packedstruct(i64 %idx){
-; CHECK-LABEL: @gep_i32_load_i32_align4_packedstruct(
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, ptr @constpackedstruct, i64 [[IDX:%.*]]
-; CHECK-NEXT:    [[TMP2:%.*]] = load i32, ptr [[TMP1]], align 4
-; CHECK-NEXT:    ret i32 [[TMP2]]
+; LE-LABEL: @gep_i32_load_i32_align4_packedstruct(
+; LE-NEXT:    ret i32 65537
+;
+; BE-LABEL: @gep_i32_load_i32_align4_packedstruct(
+; BE-NEXT:    ret i32 16777472
 ;
   %1 = getelementptr inbounds i32, ptr @constpackedstruct, i64 %idx
   %2 = load i32, ptr %1, align 4
@@ -75,15 +75,13 @@
 }
 
 define i32 @gep_i16_load_i32_align1(i64 %idx){
-; CHECK-LABEL: @gep_i16_load_i32_align1(
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i16, ptr @constarray, i64 [[IDX:%.*]]
-; CHECK-NEXT:    [[TMP2:%.*]] = load i32, ptr [[TMP1]], align 1
-; CHECK-NEXT:    ret i32 [[TMP2]]
+; LE-LABEL: @gep_i16_load_i32_align1(
+; LE-NEXT:    ret i32 65537
+;
+; BE-LABEL: @gep_i16_load_i32_align1(
+; BE-NEXT:    ret i32 16777472
 ;
   %1 = getelementptr inbounds i16, ptr @constarray, i64 %idx
   %2 = load i32, ptr %1, align 1
   ret i32 %2
 }
-;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
-; BE: {{.*}}
-; LE: {{.*}}