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| author | Laszlo Ersek <lersek@redhat.com> | 2018-09-29 21:22:57 +0200 |
|---|---|---|
| committer | Laszlo Ersek <lersek@redhat.com> | 2018-10-17 18:44:46 +0200 |
| commit | 7149d40938f85cfe4c29a57c7c1126247ab55b49 (patch) | |
| tree | 09897792e7bb3182a3b8e9f1f3071b901195586d /MdePkg/Library/BaseSynchronizationLib | |
| parent | c6fedbd7911c7645d2c93a865b1616ca1a2c1e63 (diff) | |
| download | edk2-7149d40938f85cfe4c29a57c7c1126247ab55b49.tar.gz edk2-7149d40938f85cfe4c29a57c7c1126247ab55b49.tar.bz2 edk2-7149d40938f85cfe4c29a57c7c1126247ab55b49.zip | |
MdePkg/BaseSynchronizationLib GCC: fix InternalSyncCompareExchange32()
(This patch is identical to the last one, except for the
InternalSyncCompareExchange16() -> InternalSyncCompareExchange32() and
"cmpxchgw" -> "cmpxchgl" replacements.)
The CMPXCHG instruction has the following operands:
- AX (implicit, CompareValue): input and output
- destination operand (*Value): input and output
- source operand (ExchangeValue): input
The IA32 version of InternalSyncCompareExchange32() correctly marks
CompareValue as input/output, but it marks (*Value) only as input.
The X64 version of InternalSyncCompareExchange32() attempts to mark both
CompareValue and (*Value) as input/output, but it doesn't use the
appropriate constraints for either operand.
Fix these issues. Furthermore, prefer the short "+" constraint for I/O
operands over the <output-operand-number> constraint that can be applied
to the input instances of I/O operands.
Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1208
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Diffstat (limited to 'MdePkg/Library/BaseSynchronizationLib')
| -rw-r--r-- | MdePkg/Library/BaseSynchronizationLib/Ia32/GccInline.c | 9 | ||||
| -rw-r--r-- | MdePkg/Library/BaseSynchronizationLib/X64/GccInline.c | 10 |
2 files changed, 8 insertions, 11 deletions
diff --git a/MdePkg/Library/BaseSynchronizationLib/Ia32/GccInline.c b/MdePkg/Library/BaseSynchronizationLib/Ia32/GccInline.c index bd98a5aebf..44188e265a 100644 --- a/MdePkg/Library/BaseSynchronizationLib/Ia32/GccInline.c +++ b/MdePkg/Library/BaseSynchronizationLib/Ia32/GccInline.c @@ -155,11 +155,10 @@ InternalSyncCompareExchange32 ( {
__asm__ __volatile__ (
"lock \n\t"
- "cmpxchgl %1, %2 \n\t"
- : "=a" (CompareValue) // %0
- : "q" (ExchangeValue), // %1
- "m" (*Value), // %2
- "0" (CompareValue) // %3
+ "cmpxchgl %2, %1 \n\t"
+ : "+a" (CompareValue), // %0
+ "+m" (*Value) // %1
+ : "q" (ExchangeValue) // %2
: "memory",
"cc"
);
diff --git a/MdePkg/Library/BaseSynchronizationLib/X64/GccInline.c b/MdePkg/Library/BaseSynchronizationLib/X64/GccInline.c index 4338fb8e65..a85cf0265c 100644 --- a/MdePkg/Library/BaseSynchronizationLib/X64/GccInline.c +++ b/MdePkg/Library/BaseSynchronizationLib/X64/GccInline.c @@ -155,12 +155,10 @@ InternalSyncCompareExchange32 ( {
__asm__ __volatile__ (
"lock \n\t"
- "cmpxchgl %3, %1 \n\t"
- : "=a" (CompareValue), // %0
- "=m" (*Value) // %1
- : "a" (CompareValue), // %2
- "r" (ExchangeValue), // %3
- "m" (*Value) // %4
+ "cmpxchgl %2, %1 \n\t"
+ : "+a" (CompareValue), // %0
+ "+m" (*Value) // %1
+ : "r" (ExchangeValue) // %2
: "memory",
"cc"
);
|