Modules: Use math() for hex to decimal conversion

math() can parse hex numbers prefixed with "0x" since 3.13.

Modules/CMakeDetermineCompilerId.cmake

@@ -1094,17 +1094,7 @@ function(CMAKE_DETERMINE_COMPILER_ID_CHECK lang file)
       # The offset to the PE signature is stored at 0x3c.
       file(READ ${file} peoffsethex LIMIT 1 OFFSET 60 HEX)
       if(NOT peoffsethex STREQUAL "")
-        string(SUBSTRING "${peoffsethex}" 0 1 peoffsethex1)
-        string(SUBSTRING "${peoffsethex}" 1 1 peoffsethex2)
-        set(peoffsetexpression "${peoffsethex1} * 16 + ${peoffsethex2}")
-        string(REPLACE "a" "10" peoffsetexpression "${peoffsetexpression}")
-        string(REPLACE "b" "11" peoffsetexpression "${peoffsetexpression}")
-        string(REPLACE "c" "12" peoffsetexpression "${peoffsetexpression}")
-        string(REPLACE "d" "13" peoffsetexpression "${peoffsetexpression}")
-        string(REPLACE "e" "14" peoffsetexpression "${peoffsetexpression}")
-        string(REPLACE "f" "15" peoffsetexpression "${peoffsetexpression}")
-        math(EXPR peoffset "${peoffsetexpression}")
-
+        math(EXPR peoffset "0x${peoffsethex}")
         file(READ ${file} peheader LIMIT 6 OFFSET ${peoffset} HEX)
         if(peheader STREQUAL "50450000a201")
           set(ARCHITECTURE_ID "SH3")

Modules/FindOpenSSL.cmake

@@ -573,37 +573,6 @@ if(_OpenSSL_has_dependencies)
   _OpenSSL_add_dependencies( OPENSSL_LIBRARIES )
 endif()
 
-function(from_hex HEX DEC)
-  string(TOUPPER "${HEX}" HEX)
-  set(_res 0)
-  string(LENGTH "${HEX}" _strlen)
-
-  while (_strlen GREATER 0)
-    math(EXPR _res "${_res} * 16")
-    string(SUBSTRING "${HEX}" 0 1 NIBBLE)
-    string(SUBSTRING "${HEX}" 1 -1 HEX)
-    if (NIBBLE STREQUAL "A")
-      math(EXPR _res "${_res} + 10")
-    elseif (NIBBLE STREQUAL "B")
-      math(EXPR _res "${_res} + 11")
-    elseif (NIBBLE STREQUAL "C")
-      math(EXPR _res "${_res} + 12")
-    elseif (NIBBLE STREQUAL "D")
-      math(EXPR _res "${_res} + 13")
-    elseif (NIBBLE STREQUAL "E")
-      math(EXPR _res "${_res} + 14")
-    elseif (NIBBLE STREQUAL "F")
-      math(EXPR _res "${_res} + 15")
-    else()
-      math(EXPR _res "${_res} + ${NIBBLE}")
-    endif()
-
-    string(LENGTH "${HEX}" _strlen)
-  endwhile()
-
-  set(${DEC} ${_res} PARENT_SCOPE)
-endfunction()
-
 if(OPENSSL_INCLUDE_DIR AND EXISTS "${OPENSSL_INCLUDE_DIR}/openssl/opensslv.h")
   file(STRINGS "${OPENSSL_INCLUDE_DIR}/openssl/opensslv.h" openssl_version_str
        REGEX "^#[\t ]*define[\t ]+OPENSSL_VERSION_NUMBER[\t ]+0x([0-9a-fA-F])+.*")
@@ -620,16 +589,14 @@ if(OPENSSL_INCLUDE_DIR AND EXISTS "${OPENSSL_INCLUDE_DIR}/openssl/opensslv.h")
            "\\1;\\2;\\3;\\4;\\5" OPENSSL_VERSION_LIST "${openssl_version_str}")
     list(GET OPENSSL_VERSION_LIST 0 OPENSSL_VERSION_MAJOR)
     list(GET OPENSSL_VERSION_LIST 1 OPENSSL_VERSION_MINOR)
-    from_hex("${OPENSSL_VERSION_MINOR}" OPENSSL_VERSION_MINOR)
+    math(EXPR OPENSSL_VERSION_MINOR "0x${OPENSSL_VERSION_MINOR}")
     list(GET OPENSSL_VERSION_LIST 2 OPENSSL_VERSION_FIX)
-    from_hex("${OPENSSL_VERSION_FIX}" OPENSSL_VERSION_FIX)
+    math(EXPR OPENSSL_VERSION_FIX "0x${OPENSSL_VERSION_FIX}")
     list(GET OPENSSL_VERSION_LIST 3 OPENSSL_VERSION_PATCH)
 
     if (NOT OPENSSL_VERSION_PATCH STREQUAL "00")
-      from_hex("${OPENSSL_VERSION_PATCH}" _tmp)
       # 96 is the ASCII code of 'a' minus 1
-      math(EXPR OPENSSL_VERSION_PATCH_ASCII "${_tmp} + 96")
-      unset(_tmp)
+      math(EXPR OPENSSL_VERSION_PATCH_ASCII "0x${OPENSSL_VERSION_PATCH} + 96")
       # Once anyone knows how OpenSSL would call the patch versions beyond 'z'
       # this should be updated to handle that, too. This has not happened yet
       # so it is simply ignored here for now.