audk/ShellPkg/Library/UefiShellDebug1CommandsLib/HexEdit
Hao Wu 22454f1042 ShellPkg: Refine casting expression result to bigger size
There are cases that the operands of an expression are all with rank less
than UINT64/INT64 and the result of the expression is explicitly cast to
UINT64/INT64 to fit the target size.

An example will be:
UINT32 a,b;
// a and b can be any unsigned int type with rank less than UINT64, like
// UINT8, UINT16, etc.
UINT64 c;
c = (UINT64) (a + b);

Some static code checkers may warn that the expression result might
overflow within the rank of "int" (integer promotions) and the result is
then cast to a bigger size.

The commit refines codes by the following rules:
1). When the expression is possible to overflow the range of unsigned int/
int:
c = (UINT64)a + b;

2). When the expression will not overflow within the rank of "int", remove
the explicit type casts:
c = a + b;

3). When the expression will be cast to pointer of possible greater size:
UINT32 a,b;
VOID *c;
c = (VOID *)(UINTN)(a + b); --> c = (VOID *)((UINTN)a + b);

4). When one side of a comparison expression contains only operands with
rank less than UINT32:
UINT8 a;
UINT16 b;
UINTN c;
if ((UINTN)(a + b) > c) {...} --> if (((UINT32)a + b) > c) {...}

For rule 4), if we remove the 'UINTN' type cast like:
if (a + b > c) {...}
The VS compiler will complain with warning C4018 (signed/unsigned
mismatch, level 3 warning) due to promoting 'a + b' to type 'int'.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
2017-03-06 14:33:25 +08:00
..
BufferImage.c ShellPkg: Refine casting expression result to bigger size 2017-03-06 14:33:25 +08:00
BufferImage.h ShellPkg/UefiShellDebug1CommandsLib: Remove unnecessary EFIAPI 2016-10-09 10:27:47 +08:00
Clipboard.c add comments to function declarations and definitions and updated to match coding style document. 2011-04-05 20:55:45 +00:00
Clipboard.h add comments to function declarations and definitions and updated to match coding style document. 2011-04-05 20:55:45 +00:00
DiskImage.c ShellPkg/UefiShellDebug1CommandsLib: Remove unnecessary EFIAPI 2016-10-09 10:27:47 +08:00
DiskImage.h add comments to function declarations and definitions and updated to match coding style document. 2011-04-05 20:55:45 +00:00
FileImage.c ShellPkg: Fix typos. 2015-02-02 01:51:59 +00:00
FileImage.h add comments to function declarations and definitions and updated to match coding style document. 2011-04-05 20:55:45 +00:00
HexEdit.c ShellPkg: Standardized HP Copyright Message String 2015-02-04 22:25:01 +00:00
HexEditor.h add Edit and HexEdit commands. 2011-03-25 21:15:07 +00:00
HexEditorTypes.h ShellPkg: Fix ARM build errors. 2013-06-11 22:07:03 +00:00
HexeditStrings.uni ShellPkg: Convert all .uni files to utf-8 2015-12-09 23:07:58 +00:00
MainHexEditor.c ShellPkg/UefiShellDebug1CommandsLib: Remove unnecessary EFIAPI 2016-10-09 10:27:47 +08:00
MainHexEditor.h ShellPkg/UefiShellDebug1CommandsLib: Remove unnecessary EFIAPI 2016-10-09 10:27:47 +08:00
MemImage.c ShellPkg: Fixed build error 'variable set but not used' 2013-05-07 17:57:58 +00:00
MemImage.h add comments to function declarations and definitions and updated to match coding style document. 2011-04-05 20:55:45 +00:00
Misc.c update copyright line format 2011-06-07 08:08:19 +00:00
Misc.h add comments to function declarations and definitions and updated to match coding style document. 2011-04-05 20:55:45 +00:00