[PATCH] D154495: clang: Attach !fpmath metadata to __builtin_sqrt based on language flags

[Matt Arsenault via Phabricator via cfe-commits]

arsenm added inline comments.


================
Comment at: clang/lib/CodeGen/CGExpr.cpp:5602
+    // source are correctly rounded.
+    SetFPAccuracy(Val, 2.5);
+  }
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arsenm wrote:
> yaxunl wrote:
> > the spec says sqrt relative error is 3ULP https://registry.khronos.org/OpenCL/specs/2.2/html/OpenCL_C.html#relative-error-as-ulps
> Did that change between versions? In any case I don’t want to change the currently used threshold in this patch. We only need 1.0 anyway 
Oh, I see the threshold is 2.5 for fdiv and 3.0 for sqrt.


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  https://reviews.llvm.org/D154495/new/

https://reviews.llvm.org/D154495