src/util: minor xspan enhancements

src/conf.h

@@ -173,6 +173,7 @@ typedef upx_int64_t upx_off_t;
 #else
 #define noinline        __acc_noinline
 #endif
+#define forceinline_constexpr forceinline constexpr
 #define likely          __acc_likely
 #define unlikely        __acc_unlikely
 #define very_likely     __acc_very_likely

src/util/xspan.h

@@ -95,6 +95,11 @@ using XSPAN_NAMESPACE_NAME::raw_index_bytes; // overloaded for all classes
 #define XSPAN_P_VAR(type, var, first, ...) XSPAN_P(type) var((first), ##__VA_ARGS__)
 #define XSPAN_S_VAR(type, var, first, ...) XSPAN_S(type) var((first), ##__VA_ARGS__)
 
+// cast to a different type (creates a new value)
+#define XSPAN_0_CAST(type, var) ((var).type_cast<type>())
+#define XSPAN_P_CAST(type, var) ((var).type_cast<type>())
+#define XSPAN_S_CAST(type, var) ((var).type_cast<type>())
+
 #elif WITH_XSPAN >= 1
 
 // unchecked - just a no-op pointer wrapper, no extra functionality
@@ -114,6 +119,11 @@ using XSPAN_NAMESPACE_NAME::raw_index_bytes; // overloaded for all classes
 #define XSPAN_P_VAR(type, var, first, ...) XSPAN_P(type) var((first))
 #define XSPAN_S_VAR(type, var, first, ...) XSPAN_S(type) var((first))
 
+// cast to a different type (creates a new value)
+#define XSPAN_0_CAST(type, var)            ((var).type_cast<type>())
+#define XSPAN_P_CAST(type, var)            ((var).type_cast<type>())
+#define XSPAN_S_CAST(type, var)            ((var).type_cast<type>())
+
 #else // WITH_XSPAN
 
 // unchecked regular pointers
@@ -147,6 +157,11 @@ inline R *xspan_make_helper__(R * /*dummy*/, MemBuffer &mb) noexcept {
 #define XSPAN_P_VAR(type, var, first, ...) type *var = XSPAN_P_MAKE(type, (first))
 #define XSPAN_S_VAR(type, var, first, ...) type *var = XSPAN_S_MAKE(type, (first))
 
+// cast to a different type (creates a new value)
+#define XSPAN_0_CAST(type, var)            ((type *) (var))
+#define XSPAN_P_CAST(type, var)            ((type *) (var))
+#define XSPAN_S_CAST(type, var)            ((type *) (var))
+
 #endif // WITH_XSPAN
 
 /*************************************************************************
@@ -166,6 +181,10 @@ inline R *xspan_make_helper__(R * /*dummy*/, MemBuffer &mb) noexcept {
 #define SPAN_0_VAR  XSPAN_0_VAR
 #define SPAN_P_VAR  XSPAN_P_VAR
 #define SPAN_S_VAR  XSPAN_S_VAR
+// cast to a different type (creates a new value)
+#define SPAN_0_CAST XSPAN_0_CAST
+#define SPAN_P_CAST XSPAN_P_CAST
+#define SPAN_S_CAST XSPAN_S_CAST
 #endif
 
 /* vim:set ts=4 sw=4 et: */

src/util/xspan_fwd.h

@@ -179,6 +179,11 @@ XSPAN_FWD_TU(unsigned) ptr_udiff_bytes(const C<T> &a, const E<U> &b) {
 
 #ifdef UPX_VERSION_HEX
 
+template <class T>
+inline unsigned upx_adler32(const C<T> &a, unsigned n, unsigned adler = 1) {
+    return upx_adler32(a.raw_bytes(n), n, adler);
+}
+
 template <class T>
 unsigned get_ne16(const C<T> &a) {
     return get_ne16(a.raw_bytes(2));

src/util/xspan_impl.h

@@ -53,11 +53,11 @@ void xspan_check_range(const void *ptr, const void *base, ptrdiff_t size_in_byte
 
 // help constructor to distinguish between number of elements and bytes
 struct XSpanCount final {
-    explicit forceinline constexpr XSpanCount(size_t n) noexcept : count(n) {}
+    explicit forceinline_constexpr XSpanCount(size_t n) noexcept : count(n) {}
     size_t count; // public
 };
 struct XSpanSizeInBytes final {
-    explicit forceinline constexpr XSpanSizeInBytes(size_t bytes) noexcept : size_in_bytes(bytes) {}
+    explicit forceinline_constexpr XSpanSizeInBytes(size_t bytes) noexcept : size_in_bytes(bytes) {}
     size_t size_in_bytes; // public
 };
 
@@ -199,29 +199,22 @@ struct Ptr;
 class XSpanInternalDummyArgFake; // not implemented on purpose
 typedef XSpanInternalDummyArgFake *XSpanInternalDummyArg;
 #define XSpanInternalDummyArgInit nullptr
-#elif 1
+#elif __cplusplus >= 201103L && 1
 // use an enum
 struct XSpanInternalDummyArg final {
     enum DummyEnum {};
-    explicit forceinline constexpr XSpanInternalDummyArg(DummyEnum &&) noexcept {}
+    explicit forceinline_constexpr XSpanInternalDummyArg(DummyEnum &&) noexcept {}
 };
 #define XSpanInternalDummyArgInit                                                                  \
     (XSPAN_NS(XSpanInternalDummyArg)(XSPAN_NS(XSpanInternalDummyArg)::DummyEnum{}))
 #else
 // use a class with a private constructor
 struct XSpanInternalDummyArg final {
-    static forceinline constexpr XSpanInternalDummyArg make() noexcept {
-        return XSpanInternalDummyArg{};
+    static forceinline_constexpr XSpanInternalDummyArg make() noexcept {
+        return XSpanInternalDummyArg();
     }
 private:
-    explicit forceinline constexpr XSpanInternalDummyArg() noexcept {}
-#if !(ACC_CC_MSC) // MSVC wants to use the copy and move constructors; correct or compiler bug?
-    // @COMPILER_BUG @MSVC_BUG
-    XSpanInternalDummyArg(const XSpanInternalDummyArg &) = delete;
-    XSpanInternalDummyArg(XSpanInternalDummyArg &&) noexcept = delete;
-    XSpanInternalDummyArg &operator=(const XSpanInternalDummyArg &) = delete;
-    XSpanInternalDummyArg &operator=(XSpanInternalDummyArg &&) noexcept = delete;
-#endif
+    explicit forceinline_constexpr XSpanInternalDummyArg() noexcept {}
 };
 #define XSpanInternalDummyArgInit                                                                  \
     (XSPAN_NS(XSpanInternalDummyArg)(XSPAN_NS(XSpanInternalDummyArg)::make()))

src/util/xspan_impl_common.h

@@ -29,6 +29,7 @@
 **************************************************************************/
 
 #if CLANG_FORMAT_DUMMY_CLASS
+template <class T>
 class CSelf {
 #endif
 
@@ -68,7 +69,7 @@ private:
             xspan_check_range(ptr, base, size_in_bytes);
     }
 #else
-forceinline constexpr void assertInvariants() const noexcept {}
+forceinline_constexpr void assertInvariants() const noexcept {}
 #endif
 
     static inline pointer makeNotNull(pointer p) {
@@ -272,7 +273,7 @@ public:
     Self &operator=(MemBuffer &mb) { return assign(Self(mb)); }
 #endif
 
-    Self subspan(ptrdiff_t offset, ptrdiff_t count) {
+    Self subspan(ptrdiff_t offset, ptrdiff_t count) const {
         pointer begin = check_add(ptr, offset);
         pointer end = check_add(begin, count);
         if (begin <= end)
@@ -281,6 +282,14 @@ public:
             return Self(Unchecked, end, (begin - end) * sizeof(T), end);
     }
 
+    template <class U>
+    CSelf<U> type_cast() const {
+        assertInvariants();
+        typedef CSelf<U> R;
+        return R(R::Unchecked, reinterpret_cast<typename R::pointer>(ptr), size_in_bytes,
+                 reinterpret_cast<typename R::pointer>(base));
+    }
+
     bool operator==(pointer other) const { return ptr == other; }
     template <class U>
     XSPAN_REQUIRES_CONVERTIBLE_R(bool)

src/util/xspan_impl_ptr.h

@@ -55,7 +55,7 @@ private:
     // inverse logic for ensuring valid pointers from existing objects
     inline pointer ensurePtr() const { return ptr; }
     // debug
-    forceinline constexpr void assertInvariants() const noexcept {}
+    forceinline_constexpr void assertInvariants() const noexcept {}
 
 public:
 #if XSPAN_CONFIG_ENABLE_IMPLICIT_CONVERSION || 1