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diff --git a/erts/emulator/beam/beam_types.h b/erts/emulator/beam/beam_types.h
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+++ b/erts/emulator/beam/beam_types.h
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+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2021-2022. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+/**
+ * @description Basic type representation for BEAM instruction operands.
+ * @file beam_types.h
+ * 
+ * While the compiler is good eliminating redundant type tests and simplifying
+ * instructions, we're limited by the available instructions and it's not
+ * always worthwhile to add new variants.
+ * 
+ * The idea behind this module is to allow minor optimizations _inside_
+ * instructions based on what we know about their operand types. For example,
+ * when we know that the source passed to `is_tagged_tuple` is always boxed, we
+ * can skip the boxed check.
+ */
+
+#ifndef _BEAM_TYPES_H
+#define _BEAM_TYPES_H
+
+#include "sys.h"
+
+#define BEAM_TYPES_VERSION 1
+
+#define BEAM_TYPE_NONE               (0)
+
+#define BEAM_TYPE_ATOM               (1 << 0)
+#define BEAM_TYPE_BITSTRING          (1 << 1)
+#define BEAM_TYPE_BS_MATCHSTATE      (1 << 2)
+#define BEAM_TYPE_CONS               (1 << 3)
+#define BEAM_TYPE_FLOAT              (1 << 4)
+#define BEAM_TYPE_FUN                (1 << 5)
+#define BEAM_TYPE_INTEGER            (1 << 6)
+#define BEAM_TYPE_MAP                (1 << 7)
+#define BEAM_TYPE_NIL                (1 << 8)
+#define BEAM_TYPE_PID                (1 << 9)
+#define BEAM_TYPE_PORT               (1 << 10)
+#define BEAM_TYPE_REFERENCE          (1 << 11)
+#define BEAM_TYPE_TUPLE              (1 << 12)
+
+#define BEAM_TYPE_ANY                ((1 << 13) - 1)
+
+#define BEAM_TYPE_MASK_BOXED        \
+    (BEAM_TYPE_BITSTRING |          \
+     BEAM_TYPE_BS_MATCHSTATE |      \
+     BEAM_TYPE_FLOAT |              \
+     BEAM_TYPE_FUN |                \
+     BEAM_TYPE_INTEGER |            \
+     BEAM_TYPE_MAP |                \
+     BEAM_TYPE_PID |                \
+     BEAM_TYPE_PORT |               \
+     BEAM_TYPE_REFERENCE |          \
+     BEAM_TYPE_TUPLE)
+
+#define BEAM_TYPE_MASK_IMMEDIATE    \
+    (BEAM_TYPE_ATOM |               \
+     BEAM_TYPE_INTEGER |            \
+     BEAM_TYPE_NIL |                \
+     BEAM_TYPE_PID |                \
+     BEAM_TYPE_PORT)
+
+#define BEAM_TYPE_MASK_CELL         \
+    (BEAM_TYPE_CONS)
+
+#define BEAM_TYPE_MASK_ALWAYS_IMMEDIATE  \
+    (BEAM_TYPE_MASK_IMMEDIATE & ~(BEAM_TYPE_MASK_BOXED | BEAM_TYPE_MASK_CELL))
+#define BEAM_TYPE_MASK_ALWAYS_BOXED      \
+    (BEAM_TYPE_MASK_BOXED & ~(BEAM_TYPE_MASK_CELL | BEAM_TYPE_MASK_IMMEDIATE))
+#define BEAM_TYPE_MASK_ALWAYS_CELL       \
+    (BEAM_TYPE_MASK_CELL & ~(BEAM_TYPE_MASK_BOXED | BEAM_TYPE_MASK_IMMEDIATE))
+
+typedef struct {
+    /** @brief A set of the possible types (atom, tuple, etc) this term may
+     * be. When a single bit is set, the term will always be of that type. */
+    int type_union;
+
+    /** @brief Minimum and maximum values. Only valid if min <= max. */
+    Sint64 min;
+    Sint64 max;
+} BeamType;
+
+int beam_types_decode(const byte *data, Uint size, BeamType *out);
+
+#endif