GCC 12 (https://gcc.gnu.org/PR101696) allows `arch=x86-64`
`arch=x86-64-v2` `arch=x86-64-v3` `arch=x86-64-v4` in the
target_clones function attribute. This patch ports the feature.
* Set KeyFeature to `x86-64{,-v2,-v3,-v4}` in `Processors[]`, to be used
by X86TargetInfo::multiVersionSortPriority
* builtins: change `__cpu_features2` to an array like libgcc. Define
`FEATURE_X86_64_{BASELINE,V2,V3,V4}` and depended ISA feature bits.
* CGBuiltin.cpp: update EmitX86CpuSupports to handle `arch=x86-64*`.
Close https://github.com/llvm/llvm-project/issues/55830
Reviewed By: pengfei
Differential Revision: https://reviews.llvm.org/D158329
Previously, an attempt to declare an overload of a multiversion function
in C was not properly diagnosed. In some cases, diagnostics were simply
missing. In other cases the following assertion failure occured...
```
Assertion `(Previous.empty() || llvm::any_of(Previous, [](const NamedDecl *ND) { return ND->hasAttr(); })) && "Non-redecls shouldn't happen without overloadable present"' failed.
```
... or the following diagnostic was spuriously issued.
```
error: at most one overload for a given name may lack the 'overloadable' attribute
```
The diagnostics issued in some cases could be improved. When the function
type of a redeclaration does not match the prior declaration, it would be
preferable to diagnose the type mismatch before diagnosing mismatched
attributes. Diagnostics are also missing for some cases.
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D121959
This change adds test cases to validate diagnostics for overloaded sets
that contain declarations of multiversion functions. Many of the added test
cases exercise declarations that are intended to be valid. Others are
intended to be valid if and when restrictions on multiversion functions
being declared with the overloadable attribute are lifted.
Several of the new test cases currently trigger the following assertion
failure in SemaDecl.cpp; the relevant test is therefore marked as an
expected failure pending a fix.
```
Assertion `(Previous.empty() || llvm::any_of(Previous, [](const NamedDecl *ND) { return ND->hasAttr(); })) && "Non-redecls shouldn't happen without overloadable present"' failed.
```
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D121954
A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,
void func();
becomes
void func(void);
This is the first batch of tests being updated (there are a significant
number of other tests left to be updated).
See discussion in D51650, this change was a little aggressive in an
error while doing a 'while we were here', so this removes that error
condition, as it is apparently useful.
This reverts commit bb4934601d731465e01e2e22c80ce2dbe687d73f.
As discussed here: https://lwn.net/Articles/691932/
GCC6.0 adds target_clones multiversioning. This functionality is
an odd cross between the cpu_dispatch and 'target' MV, but is compatible
with neither.
This attribute allows you to list all options, then emits a separately
optimized version of each function per-option (similar to the
cpu_specific attribute). It automatically generates a resolver, just
like the other two.
The mangling however, is... ODD to say the least. The mangling format
is:
<normal_mangling>.<option string>.<option ordinal>.
Differential Revision:https://reviews.llvm.org/D51650
