[InstCombine] Add pre-commit tests

Author: pedroclobo

llvm/test/Transforms/InstCombine/load-store-forward.ll

@@ -379,6 +379,45 @@ define i32 @load_after_memset_0_offset(ptr %a) {
   ret i32 %v
 }
 
+define i32 @load_after_memset_1_offset(ptr %a) {
+; CHECK-LABEL: @load_after_memset_1_offset(
+; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr noundef nonnull align 1 dereferenceable(16) [[A:%.*]], i8 1, i64 16, i1 false)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i8, ptr [[A]], i64 4
+; CHECK-NEXT:    [[V:%.*]] = load i32, ptr [[GEP]], align 4
+; CHECK-NEXT:    ret i32 [[V]]
+;
+  call void @llvm.memset.p0.i64(ptr %a, i8 1, i64 16, i1 false)
+  %gep = getelementptr i8, ptr %a, i64 4
+  %v = load i32, ptr %gep
+  ret i32 %v
+}
+
+define i1 @neg_load_after_memset_0_offset_i1(ptr %a) {
+; CHECK-LABEL: @neg_load_after_memset_0_offset_i1(
+; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr noundef nonnull align 1 dereferenceable(16) [[A:%.*]], i8 15, i64 16, i1 false)
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i8, ptr [[A]], i64 12
+; CHECK-NEXT:    [[V:%.*]] = load i1, ptr [[GEP]], align 1
+; CHECK-NEXT:    ret i1 [[V]]
+;
+  call void @llvm.memset.p0.i64(ptr %a, i8 15, i64 16, i1 false)
+  %gep = getelementptr i1, ptr %a, i64 12
+  %v = load i1, ptr %gep
+  ret i1 %v
+}
+
+define i8 @neg_load_after_memset_0_neg_offset(ptr %a) {
+; CHECK-LABEL: @neg_load_after_memset_0_neg_offset(
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i8, ptr [[A:%.*]], i64 2
+; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr noundef nonnull align 1 dereferenceable(16) [[GEP]], i8 15, i64 16, i1 false)
+; CHECK-NEXT:    [[V:%.*]] = load i8, ptr [[A]], align 1
+; CHECK-NEXT:    ret i8 [[V]]
+;
+  %gep = getelementptr i8, ptr %a, i64 2
+  call void @llvm.memset.p0.i64(ptr %gep, i8 15, i64 16, i1 false)
+  %v = load i8, ptr %a
+  ret i8 %v
+}
+
 define i32 @load_after_memset_0_offset_too_large(ptr %a) {
 ; CHECK-LABEL: @load_after_memset_0_offset_too_large(
 ; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr noundef nonnull align 1 dereferenceable(16) [[A:%.*]], i8 0, i64 16, i1 false)