MdePkg: 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: Laszlo Ersek <lersek@redhat.com>
This commit is contained in:
@@ -3,7 +3,7 @@
|
||||
the PCI operations to be replayed during an S3 resume. This library class
|
||||
maps directly on top of the PciLib class.
|
||||
|
||||
Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>
|
||||
Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
|
||||
|
||||
This program and the accompanying materials
|
||||
are licensed and made available under the terms and conditions
|
||||
@@ -25,7 +25,7 @@
|
||||
#include <Library/S3PciLib.h>
|
||||
|
||||
#define PCILIB_TO_COMMON_ADDRESS(Address) \
|
||||
((UINT64) ((((UINTN) ((Address>>20) & 0xff)) << 24) + (((UINTN) ((Address>>15) & 0x1f)) << 16) + (((UINTN) ((Address>>12) & 0x07)) << 8) + ((UINTN) (Address & 0xfff ))))
|
||||
((((UINTN) ((Address>>20) & 0xff)) << 24) + (((UINTN) ((Address>>15) & 0x1f)) << 16) + (((UINTN) ((Address>>12) & 0x07)) << 8) + ((UINTN) (Address & 0xfff )))
|
||||
|
||||
/**
|
||||
Saves a PCI configuration value to the boot script.
|
||||
|
Reference in New Issue
Block a user