[PATCH] D131526: [OMPIRBuilder] Add support for safelen clause

[Prabhdeep Soni via Phabricator via cfe-commits]

psoni2628 added inline comments.


================
Comment at: llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp:3045
+  if (!(Simdlen == nullptr && Safelen == nullptr)) {
+    ConstantInt *VectorizeWidth = Simdlen == nullptr ? Safelen : Simdlen;
     addLoopMetadata(
----------------
domada wrote:
> Could you add comment which describes how simdlen and safelen clauses work?
> 
> BTW. Have you checked invalid test case where safelen < simdlen? 
Yes, I have checked this case, the case doesn't make it to OMPIRBuilder, because the frontend errors.


```
./ex2.c:9:38: error: the value of 'simdlen' parameter must be less than or equal to the value of the 'safelen' parameter
        #pragma omp simd safelen(2) simdlen(3)
                                 ~          ^
1 error generated.

```

I was thinking about adding an assertion to assert that `simdlen < safelen` , but I wasn't sure that it made sense to do so when Clang is checking this anyways, and the existing codegen for simdlen/safelen also doesn't check this.


```
+  // If both simdlen and safelen clauses are specified, the value of the simdlen parameter must be less than or equal to the value of the safelen parameter.
+  if (Simdlen != nullptr && Safelen != nullptr &&  (Simdlen->getValue().ugt(Safelen->getValue()))) {
+    llvm_unreachable("Simdlen must be less than or to Safelen when both present");
+  }

```


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D131526/new/

https://reviews.llvm.org/D131526