r298956 - Default enable the rtm feature only on skylake and later for now because Intel disabled the feature on some haswell and broadwell processors:

[Craig Topper via cfe-commits]

So if you use -march=hsw the backend will think rtm is enabled, but clang
will block the intrinsics in the frontend?

Not sure what you mean by split the haswell and broadwell cpu.

~Craig

On Tue, Mar 28, 2017 at 4:18 PM, Eric Christopher <echristo at gmail.com>
wrote:

> Hi Craig, Quentin, Jim,
>
> Just bringing this patch to your attention here. I haven't turned it off
> in the backend since some processors do support it and we want to allow the
> code generation, with this change we simply make the user use -mrtm to get
> the functionality for now.
>
> Question: Do we want to split the haswell and broadwell cpu to handle this
> different feature set or just leave it as an optional "enable it yourself"
> since it's an errata fix?
>
> I went ahead and committed with this question outstanding so that users
> won't get illegal instructions if they happen to have the affected units.
>
> -eric
>
>
> On Tue, Mar 28, 2017 at 4:15 PM Eric Christopher via cfe-commits <
> cfe-commits at lists.llvm.org> wrote:
>
>> Author: echristo
>> Date: Tue Mar 28 18:03:19 2017
>> New Revision: 298956
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=298956&view=rev
>> Log:
>> Default enable the rtm feature only on skylake and later for now because
>> Intel disabled the feature on some haswell and broadwell processors:
>>
>> http://www.intel.com/content/dam/www/public/us/en/
>> documents/specification-updates/core-m-processor-family-spec-update.pdf
>>
>> the -mrtm option will still work normally.
>>
>> Modified:
>>     cfe/trunk/lib/Basic/Targets.cpp
>>     cfe/trunk/test/Preprocessor/predefined-arch-macros.c
>>
>> Modified: cfe/trunk/lib/Basic/Targets.cpp
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Basic/
>> Targets.cpp?rev=298956&r1=298955&r2=298956&view=diff
>> ============================================================
>> ==================
>> --- cfe/trunk/lib/Basic/Targets.cpp (original)
>> +++ cfe/trunk/lib/Basic/Targets.cpp Tue Mar 28 18:03:19 2017
>> @@ -3194,6 +3194,7 @@ bool X86TargetInfo::initFeatureMap(
>>      setFeatureEnabledImpl(Features, "mpx", true);
>>      setFeatureEnabledImpl(Features, "sgx", true);
>>      setFeatureEnabledImpl(Features, "clflushopt", true);
>> +    setFeatureEnabledImpl(Features, "rtm", true);
>>      LLVM_FALLTHROUGH;
>>    case CK_Broadwell:
>>      setFeatureEnabledImpl(Features, "rdseed", true);
>> @@ -3204,7 +3205,6 @@ bool X86TargetInfo::initFeatureMap(
>>      setFeatureEnabledImpl(Features, "lzcnt", true);
>>      setFeatureEnabledImpl(Features, "bmi", true);
>>      setFeatureEnabledImpl(Features, "bmi2", true);
>> -    setFeatureEnabledImpl(Features, "rtm", true);
>>      setFeatureEnabledImpl(Features, "fma", true);
>>      setFeatureEnabledImpl(Features, "movbe", true);
>>      LLVM_FALLTHROUGH;
>>
>> Modified: cfe/trunk/test/Preprocessor/predefined-arch-macros.c
>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/
>> Preprocessor/predefined-arch-macros.c?rev=298956&r1=298955&
>> r2=298956&view=diff
>> ============================================================
>> ==================
>> --- cfe/trunk/test/Preprocessor/predefined-arch-macros.c (original)
>> +++ cfe/trunk/test/Preprocessor/predefined-arch-macros.c Tue Mar 28
>> 18:03:19 2017
>> @@ -525,7 +525,6 @@
>>  // CHECK_CORE_AVX2_M32: #define __PCLMUL__ 1
>>  // CHECK_CORE_AVX2_M32: #define __POPCNT__ 1
>>  // CHECK_CORE_AVX2_M32: #define __RDRND__ 1
>> -// CHECK_CORE_AVX2_M32: #define __RTM__ 1
>>  // CHECK_CORE_AVX2_M32: #define __SSE2__ 1
>>  // CHECK_CORE_AVX2_M32: #define __SSE3__ 1
>>  // CHECK_CORE_AVX2_M32: #define __SSE4_1__ 1
>> @@ -555,7 +554,6 @@
>>  // CHECK_CORE_AVX2_M64: #define __PCLMUL__ 1
>>  // CHECK_CORE_AVX2_M64: #define __POPCNT__ 1
>>  // CHECK_CORE_AVX2_M64: #define __RDRND__ 1
>> -// CHECK_CORE_AVX2_M64: #define __RTM__ 1
>>  // CHECK_CORE_AVX2_M64: #define __SSE2_MATH__ 1
>>  // CHECK_CORE_AVX2_M64: #define __SSE2__ 1
>>  // CHECK_CORE_AVX2_M64: #define __SSE3__ 1
>> @@ -591,7 +589,6 @@
>>  // CHECK_BROADWELL_M32: #define __POPCNT__ 1
>>  // CHECK_BROADWELL_M32: #define __RDRND__ 1
>>  // CHECK_BROADWELL_M32: #define __RDSEED__ 1
>> -// CHECK_BROADWELL_M32: #define __RTM__ 1
>>  // CHECK_BROADWELL_M32: #define __SSE2__ 1
>>  // CHECK_BROADWELL_M32: #define __SSE3__ 1
>>  // CHECK_BROADWELL_M32: #define __SSE4_1__ 1
>> @@ -623,7 +620,6 @@
>>  // CHECK_BROADWELL_M64: #define __POPCNT__ 1
>>  // CHECK_BROADWELL_M64: #define __RDRND__ 1
>>  // CHECK_BROADWELL_M64: #define __RDSEED__ 1
>> -// CHECK_BROADWELL_M64: #define __RTM__ 1
>>  // CHECK_BROADWELL_M64: #define __SSE2_MATH__ 1
>>  // CHECK_BROADWELL_M64: #define __SSE2__ 1
>>  // CHECK_BROADWELL_M64: #define __SSE3__ 1
>>
>>
>> _______________________________________________
>> cfe-commits mailing list
>> cfe-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20170328/8c13ac68/attachment-0001.html>