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'.
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
---
MdePkg/Library/BaseLib/String.c | 4 ++--
MdePkg/Library/BasePeCoffLib/BasePeCoff.c | 12 +++++-------
MdePkg/Library/BaseS3PciLib/S3PciLib.c | 4 ++--
MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c | 4 ++--
MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c | 4 ++--
5 files changed, 13 insertions(+), 15 deletions(-)
diff --git a/MdePkg/Library/BaseLib/String.c b/MdePkg/Library/BaseLib/String.c
index e84bf50..4151e0e 100644
--- a/MdePkg/Library/BaseLib/String.c
+++ b/MdePkg/Library/BaseLib/String.c
@@ -586,7 +586,7 @@ InternalHexCharToUintn (
return Char - L'0';
}
- return (UINTN) (10 + InternalCharToUpper (Char) - L'A');
+ return (10 + InternalCharToUpper (Char) - L'A');
}
/**
@@ -1211,7 +1211,7 @@ InternalAsciiHexCharToUintn (
return Char - '0';
}
- return (UINTN) (10 + InternalBaseLibAsciiToUpper (Char) - 'A');
+ return (10 + InternalBaseLibAsciiToUpper (Char) - 'A');
}
diff --git a/MdePkg/Library/BasePeCoffLib/BasePeCoff.c b/MdePkg/Library/BasePeCoffLib/BasePeCoff.c
index 33cad23..8d1daba 100644
--- a/MdePkg/Library/BasePeCoffLib/BasePeCoff.c
+++ b/MdePkg/Library/BasePeCoffLib/BasePeCoff.c
@@ -15,7 +15,7 @@
PeCoffLoaderGetPeHeader() routine will do basic check for PE/COFF header.
PeCoffLoaderGetImageInfo() routine will do basic check for whole PE/COFF image.
- Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
@@ -703,12 +703,10 @@ PeCoffLoaderGetImageInfo (
//
DebugDirectoryEntryFileOffset = 0;
- SectionHeaderOffset = (UINTN)(
- ImageContext->PeCoffHeaderOffset +
- sizeof (UINT32) +
- sizeof (EFI_IMAGE_FILE_HEADER) +
- Hdr.Pe32->FileHeader.SizeOfOptionalHeader
- );
+ SectionHeaderOffset = ImageContext->PeCoffHeaderOffset +
+ sizeof (UINT32) +
+ sizeof (EFI_IMAGE_FILE_HEADER) +
+ Hdr.Pe32->FileHeader.SizeOfOptionalHeader;
for (Index = 0; Index < Hdr.Pe32->FileHeader.NumberOfSections; Index++) {
//
diff --git a/MdePkg/Library/BaseS3PciLib/S3PciLib.c b/MdePkg/Library/BaseS3PciLib/S3PciLib.c
index e29f7fe..27342b0 100644
--- a/MdePkg/Library/BaseS3PciLib/S3PciLib.c
+++ b/MdePkg/Library/BaseS3PciLib/S3PciLib.c
@@ -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.
diff --git a/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c b/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c
index 937165a..592cced 100644
--- a/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c
+++ b/MdePkg/Library/SmmMemoryAllocationLib/MemoryAllocationLib.c
@@ -12,7 +12,7 @@
allocation for the Reserved memory types are not supported and will always
return NULL.
- Copyright (c) 2006 - 2015, 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 of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -343,7 +343,7 @@ InternalAllocateAlignedPages (
Status = gSmst->SmmFreePages (Memory, UnalignedPages);
ASSERT_EFI_ERROR (Status);
}
- Memory = (EFI_PHYSICAL_ADDRESS) (AlignedMemory + EFI_PAGES_TO_SIZE (Pages));
+ Memory = AlignedMemory + EFI_PAGES_TO_SIZE (Pages);
UnalignedPages = RealPages - Pages - UnalignedPages;
if (UnalignedPages > 0) {
//
diff --git a/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c b/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c
index 3da5e211..3bd3aef 100644
--- a/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c
+++ b/MdePkg/Library/UefiMemoryAllocationLib/MemoryAllocationLib.c
@@ -2,7 +2,7 @@
Support routines for memory allocation routines based
on boot services for Dxe phase drivers.
- Copyright (c) 2006 - 2015, 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 of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -216,7 +216,7 @@ InternalAllocateAlignedPages (
Status = gBS->FreePages (Memory, UnalignedPages);
ASSERT_EFI_ERROR (Status);
}
- Memory = (EFI_PHYSICAL_ADDRESS) (AlignedMemory + EFI_PAGES_TO_SIZE (Pages));
+ Memory = AlignedMemory + EFI_PAGES_TO_SIZE (Pages);
UnalignedPages = RealPages - Pages - UnalignedPages;
if (UnalignedPages > 0) {
//
--
1.9.5.msysgit.0
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