MdeModulePkg: 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: Feng Tian <feng.tian@intel.com>
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@ -3754,8 +3754,8 @@ InitNonVolatileVariableStore (
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return EFI_VOLUME_CORRUPTED;
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}
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VariableStoreBase = (EFI_PHYSICAL_ADDRESS) ((UINTN) FvHeader + FvHeader->HeaderLength);
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VariableStoreLength = (UINT64) (NvStorageSize - FvHeader->HeaderLength);
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VariableStoreBase = (UINTN) FvHeader + FvHeader->HeaderLength;
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VariableStoreLength = NvStorageSize - FvHeader->HeaderLength;
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mNvFvHeaderCache = FvHeader;
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mVariableModuleGlobal->VariableGlobal.NonVolatileVariableBase = VariableStoreBase;
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@ -4099,7 +4099,7 @@ VariableCommonInitialize (
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GuidHob = GetFirstGuidHob (VariableGuid);
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if (GuidHob != NULL) {
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VariableStoreHeader = GET_GUID_HOB_DATA (GuidHob);
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VariableStoreLength = (UINT64) (GuidHob->Header.HobLength - sizeof (EFI_HOB_GUID_TYPE));
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VariableStoreLength = GuidHob->Header.HobLength - sizeof (EFI_HOB_GUID_TYPE);
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if (GetVariableStoreStatus (VariableStoreHeader) == EfiValid) {
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mVariableModuleGlobal->VariableGlobal.HobVariableBase = (EFI_PHYSICAL_ADDRESS) (UINTN) AllocateRuntimeCopyPool ((UINTN) VariableStoreLength, (VOID *) VariableStoreHeader);
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if (mVariableModuleGlobal->VariableGlobal.HobVariableBase == 0) {
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