Index: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -2989,8 +2989,15 @@
       if (Field) {
         // N = N + Offset
         uint64_t Offset = DL->getStructLayout(StTy)->getElementOffset(Field);
+
+        // In an inbouds GEP with an offset that is nonnegative even when
+        // interpreted as signed, assume there is no unsigned overflow.
+        SDNodeFlags Flags;
+        if (int64_t(Offset) >= 0 && cast<GEPOperator>(I).isInBounds())
+          Flags.setNoUnsignedWrap(true);
+
         N = DAG.getNode(ISD::ADD, dl, N.getValueType(), N,
-                        DAG.getConstant(Offset, dl, N.getValueType()));
+                        DAG.getConstant(Offset, dl, N.getValueType()), &Flags);
       }
 
       Ty = StTy->getElementType(Field);
@@ -3015,7 +3022,14 @@
         SDValue OffsVal = VectorWidth ?
           DAG.getConstant(Offs, dl, MVT::getVectorVT(PtrTy, VectorWidth)) :
           DAG.getConstant(Offs, dl, PtrTy);
-        N = DAG.getNode(ISD::ADD, dl, N.getValueType(), N, OffsVal);
+
+        // In an inbouds GEP with an offset that is nonnegative even when
+        // interpreted as signed, assume there is no unsigned overflow.
+        SDNodeFlags Flags;
+        if (Offs.isNonNegative() && cast<GEPOperator>(I).isInBounds())
+          Flags.setNoUnsignedWrap(true);
+
+        N = DAG.getNode(ISD::ADD, dl, N.getValueType(), N, OffsVal, &Flags);
         continue;
       }
 
Index: test/CodeGen/WebAssembly/offset.ll
===================================================================
--- test/CodeGen/WebAssembly/offset.ll
+++ test/CodeGen/WebAssembly/offset.ll
@@ -17,6 +17,28 @@
   ret i32 %t
 }
 
+; With an inbounds gep, we can fold an offset.
+
+; CHECK-LABEL: load_i32_with_folded_gep_offset:
+; CHECK: i32.load  $push0=, 24($0){{$}}
+define i32 @load_i32_with_folded_gep_offset(i32* %p) {
+  %s = getelementptr inbounds i32, i32* %p, i32 6
+  %t = load i32, i32* %s
+  ret i32 %t
+}
+
+; We can't fold a negative offset though, even with an inbounds gep.
+
+; CHECK-LABEL: load_i32_with_unfolded_gep_negative_offset:
+; CHECK: i32.const $push0=, -24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i32.load  $push2=, 0($pop1){{$}}
+define i32 @load_i32_with_unfolded_gep_negative_offset(i32* %p) {
+  %s = getelementptr inbounds i32, i32* %p, i32 -6
+  %t = load i32, i32* %s
+  ret i32 %t
+}
+
 ; Without nuw, and even with nsw, we can't fold an offset.
 
 ; CHECK-LABEL: load_i32_with_unfolded_offset:
@@ -31,6 +53,18 @@
   ret i32 %t
 }
 
+; Without inbounds, we can't fold a gep offset.
+
+; CHECK-LABEL: load_i32_with_unfolded_gep_offset:
+; CHECK: i32.const $push0=, 24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i32.load  $push2=, 0($pop1){{$}}
+define i32 @load_i32_with_unfolded_gep_offset(i32* %p) {
+  %s = getelementptr i32, i32* %p, i32 6
+  %t = load i32, i32* %s
+  ret i32 %t
+}
+
 ; Same as above but with i64.
 
 ; CHECK-LABEL: load_i64_with_folded_offset:
@@ -45,6 +79,28 @@
 
 ; Same as above but with i64.
 
+; CHECK-LABEL: load_i64_with_folded_gep_offset:
+; CHECK: i64.load  $push0=, 24($0){{$}}
+define i64 @load_i64_with_folded_gep_offset(i64* %p) {
+  %s = getelementptr inbounds i64, i64* %p, i32 3
+  %t = load i64, i64* %s
+  ret i64 %t
+}
+
+; Same as above but with i64.
+
+; CHECK-LABEL: load_i64_with_unfolded_gep_negative_offset:
+; CHECK: i32.const $push0=, -24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i64.load  $push2=, 0($pop1){{$}}
+define i64 @load_i64_with_unfolded_gep_negative_offset(i64* %p) {
+  %s = getelementptr inbounds i64, i64* %p, i32 -3
+  %t = load i64, i64* %s
+  ret i64 %t
+}
+
+; Same as above but with i64.
+
 ; CHECK-LABEL: load_i64_with_unfolded_offset:
 ; CHECK: i32.const $push0=, 24{{$}}
 ; CHECK: i32.add   $push1=, $0, $pop0{{$}}
@@ -57,6 +113,18 @@
   ret i64 %t
 }
 
+; Same as above but with i64.
+
+; CHECK-LABEL: load_i64_with_unfolded_gep_offset:
+; CHECK: i32.const $push0=, 24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i64.load  $push2=, 0($pop1){{$}}
+define i64 @load_i64_with_unfolded_gep_offset(i64* %p) {
+  %s = getelementptr i64, i64* %p, i32 3
+  %t = load i64, i64* %s
+  ret i64 %t
+}
+
 ; Same as above but with store.
 
 ; CHECK-LABEL: store_i32_with_folded_offset:
@@ -71,6 +139,28 @@
 
 ; Same as above but with store.
 
+; CHECK-LABEL: store_i32_with_folded_gep_offset:
+; CHECK: i32.store $discard=, 24($0), $pop0{{$}}
+define void @store_i32_with_folded_gep_offset(i32* %p) {
+  %s = getelementptr inbounds i32, i32* %p, i32 6
+  store i32 0, i32* %s
+  ret void
+}
+
+; Same as above but with store.
+
+; CHECK-LABEL: store_i32_with_unfolded_gep_negative_offset:
+; CHECK: i32.const $push0=, -24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i32.store $discard=, 0($pop1), $pop2{{$}}
+define void @store_i32_with_unfolded_gep_negative_offset(i32* %p) {
+  %s = getelementptr inbounds i32, i32* %p, i32 -6
+  store i32 0, i32* %s
+  ret void
+}
+
+; Same as above but with store.
+
 ; CHECK-LABEL: store_i32_with_unfolded_offset:
 ; CHECK: i32.const $push0=, 24{{$}}
 ; CHECK: i32.add   $push1=, $0, $pop0{{$}}
@@ -83,6 +173,18 @@
   ret void
 }
 
+; Same as above but with store.
+
+; CHECK-LABEL: store_i32_with_unfolded_gep_offset:
+; CHECK: i32.const $push0=, 24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i32.store $discard=, 0($pop1), $pop2{{$}}
+define void @store_i32_with_unfolded_gep_offset(i32* %p) {
+  %s = getelementptr i32, i32* %p, i32 6
+  store i32 0, i32* %s
+  ret void
+}
+
 ; Same as above but with store with i64.
 
 ; CHECK-LABEL: store_i64_with_folded_offset:
@@ -97,6 +199,28 @@
 
 ; Same as above but with store with i64.
 
+; CHECK-LABEL: store_i64_with_folded_gep_offset:
+; CHECK: i64.store $discard=, 24($0), $pop0{{$}}
+define void @store_i64_with_folded_gep_offset(i64* %p) {
+  %s = getelementptr inbounds i64, i64* %p, i32 3
+  store i64 0, i64* %s
+  ret void
+}
+
+; Same as above but with store with i64.
+
+; CHECK-LABEL: store_i64_with_unfolded_gep_negative_offset:
+; CHECK: i32.const $push0=, -24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i64.store $discard=, 0($pop1), $pop2{{$}}
+define void @store_i64_with_unfolded_gep_negative_offset(i64* %p) {
+  %s = getelementptr inbounds i64, i64* %p, i32 -3
+  store i64 0, i64* %s
+  ret void
+}
+
+; Same as above but with store with i64.
+
 ; CHECK-LABEL: store_i64_with_unfolded_offset:
 ; CHECK: i32.const $push0=, 24{{$}}
 ; CHECK: i32.add   $push1=, $0, $pop0{{$}}
@@ -109,6 +233,18 @@
   ret void
 }
 
+; Same as above but with store with i64.
+
+; CHECK-LABEL: store_i64_with_unfolded_gep_offset:
+; CHECK: i32.const $push0=, 24{{$}}
+; CHECK: i32.add   $push1=, $0, $pop0{{$}}
+; CHECK: i64.store $discard=, 0($pop1), $pop2{{$}}
+define void @store_i64_with_unfolded_gep_offset(i64* %p) {
+  %s = getelementptr i64, i64* %p, i32 3
+  store i64 0, i64* %s
+  ret void
+}
+
 ; When loading from a fixed address, materialize a zero.
 
 ; CHECK-LABEL: load_i32_from_numeric_address
@@ -159,6 +295,17 @@
   ret i32 %u
 }
 
+; Fold a gep offset into a sign-extending load.
+
+; CHECK-LABEL: load_i8_s_with_folded_gep_offset:
+; CHECK: i32.load8_s $push0=, 24($0){{$}}
+define i32 @load_i8_s_with_folded_gep_offset(i8* %p) {
+  %s = getelementptr inbounds i8, i8* %p, i32 24
+  %t = load i8, i8* %s
+  %u = sext i8 %t to i32
+  ret i32 %u
+}
+
 ; Fold an offset into a zero-extending load.
 
 ; CHECK-LABEL: load_i8_u_with_folded_offset:
@@ -172,6 +319,17 @@
   ret i32 %u
 }
 
+; Fold a gep offset into a zero-extending load.
+
+; CHECK-LABEL: load_i8_u_with_folded_gep_offset:
+; CHECK: i32.load8_u $push0=, 24($0){{$}}
+define i32 @load_i8_u_with_folded_gep_offset(i8* %p) {
+  %s = getelementptr inbounds i8, i8* %p, i32 24
+  %t = load i8, i8* %s
+  %u = zext i8 %t to i32
+  ret i32 %u
+}
+
 ; Fold an offset into a truncating store.
 
 ; CHECK-LABEL: store_i8_with_folded_offset:
@@ -183,3 +341,13 @@
   store i8 0, i8* %s
   ret void
 }
+
+; Fold a gep offset into a truncating store.
+
+; CHECK-LABEL: store_i8_with_folded_gep_offset:
+; CHECK: i32.store8 $discard=, 24($0), $pop0{{$}}
+define void @store_i8_with_folded_gep_offset(i8* %p) {
+  %s = getelementptr inbounds i8, i8* %p, i32 24
+  store i8 0, i8* %s
+  ret void
+}