audk/SourceLevelDebugPkg
Hao Wu 3ee1680978 SourceLevelDebugPkg: 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: Jeff Fan <jeff.fan@intel.com>
2017-03-06 14:33:25 +08:00
..
DebugAgentDxe SourceLevelDebugPkg: Convert all .uni files to utf-8 2015-12-15 04:58:48 +00:00
DebugAgentPei SourceLevelDebugPkg: Convert all .uni files to utf-8 2015-12-15 04:58:48 +00:00
Include SourceLevelDebugPkg: Fix typos in comments 2016-10-24 09:10:15 +08:00
Library SourceLevelDebugPkg: Refine casting expression result to bigger size 2017-03-06 14:33:25 +08:00
Contributions.txt
License.txt
Readme.txt
SourceLevelDebugPkg.dec SourceLevelDebugPkg: Update package version to 0.96 to reflect new changes 2015-08-24 06:38:24 +00:00
SourceLevelDebugPkg.dsc SourceLevelDebugPkg DSC: Add build option to disable deprecated APIs 2016-08-08 11:00:11 +08:00
SourceLevelDebugPkg.uni SourceLevelDebugPkg: Convert all .uni files to utf-8 2015-12-15 04:58:48 +00:00
SourceLevelDebugPkgExtra.uni SourceLevelDebugPkg: Convert all .uni files to utf-8 2015-12-15 04:58:48 +00:00

Readme.txt

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UDK based firmware on UEFI IA-32 and UEFI x64 platforms can be debugged with
SourceLevelDebugPkg in conjunction with Intel(R) UEFI Development Kit Debugger
Tool (Intel (R) UDK Debugger Tool).

The Intel(R) UDK Debugger Tool and its detailed user manual can be obtained
from: http://www.uefidk.com/develop.