17634d026f
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1197 Today's InterlockedIncrement()/InterlockedDecrement() guarantees to perform atomic increment/decrement but doesn't guarantee the return value equals to the new value. The patch fixes the behavior to use "XADD" instruction to guarantee the return value equals to the new value. The patch calls intrinsic functions for MSVC tool chain, calls the NASM implementation for INTEL tool chain and calls GCC inline assembly implementation (GccInline.c) for GCC tool chain. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com> Cc: Michael D Kinney <michael.d.kinney@intel.com>
47 lines
1.3 KiB
C
47 lines
1.3 KiB
C
/** @file
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InterlockedDecrement function
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Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
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This program and the accompanying materials
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are licensed and made available under the terms and conditions of the BSD License
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which accompanies this distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php.
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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**/
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/**
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Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.
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**/
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long _InterlockedDecrement(
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long * lpAddend
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);
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#pragma intrinsic(_InterlockedDecrement)
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/**
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Performs an atomic decrement of an 32-bit unsigned integer.
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Performs an atomic decrement of the 32-bit unsigned integer specified by
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Value and returns the decrement value. The decrement operation must be
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performed using MP safe mechanisms. The state of the return value is not
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guaranteed to be MP safe.
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@param Value A pointer to the 32-bit value to decrement.
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@return The decrement value.
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**/
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UINT32
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EFIAPI
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InternalSyncDecrement (
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IN volatile UINT32 *Value
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)
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{
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return _InterlockedDecrement ((long *)(Value));
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}
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