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MdePkg/BaseSafeIntLib: Fix VS20xx IA32 link failures 

https://bugzilla.tianocore.org/show_bug.cgi?id=2525

SafeUint64Mult() looks for 64-bit overflows and performs
several 32-bit multiples with 64-bit results to check for
all possible overflow conditions.  IA32 builds using VS20xx
with optimizations enabled are producing a reference to
the _allmull intrinsic.

The fix is to use MultU64x64() instead of '*' for
these operations.  These are safe because the inputs
are guaranteed to have the upper 32-bits clear, which
means MultU64x64() can never overflow with those inputs.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Bret Barkelew <Bret.Barkelew@microsoft.com>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Bret Barkelew <bret.barkelew@microsoft.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
This commit is contained in:
Michael D Kinney 2020-02-12 13:17:24 -08:00 committed by mergify[bot]
parent ec97412b7c
commit 02b7b861b1
1 changed files with 3 additions and 3 deletions
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6
MdePkg/Library/BaseSafeIntLib/SafeIntLib.c
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@ -3380,14 +3380,14 @@ SafeUint64Mult (
//
// a * d must be less than 2^32 or there would be bits set in the high 64-bits
//
ProductAD = (((UINT64)DwordA) *(UINT64)DwordD);
ProductAD = MultU64x64 ((UINT64)DwordA, (UINT64)DwordD);
if ((ProductAD & 0xffffffff00000000) == 0) {
DwordB = (UINT32)Multiplicand;
//
// b * c must be less than 2^32 or there would be bits set in the high 64-bits
//
ProductBC = (((UINT64)DwordB) *(UINT64)DwordC);
ProductBC = MultU64x64 ((UINT64)DwordB, (UINT64)DwordC);
if ((ProductBC & 0xffffffff00000000) == 0) {
//
// now sum them all up checking for overflow.
@ -3397,7 +3397,7 @@ SafeUint64Mult (
//
// b * d
//
ProductBD = (((UINT64)DwordB) *(UINT64)DwordD);
ProductBD = MultU64x64 ((UINT64)DwordB, (UINT64)DwordD);
if (!RETURN_ERROR (SafeUint64Add (UnsignedResult, ProductBD, &UnsignedResult))) {
*Result = UnsignedResult;