[PATCH] D110579: [AMDGPU] Add two new intrinsics to control fp_trunc rounding mode

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:6337
+    const Function *F = I.getCalledFunction();
+    bool HasChain = !F->doesNotAccessMemory();
+    bool OnlyLoad = HasChain && F->onlyReadsMemory();
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craig.topper wrote:
> craig.topper wrote:
> > Why would this intrinsic ever have a chain?
> Err. I guess the intrinsic attributes are defined to always have a Chain. Should it be IntrNoMem instead?
IIUC, if the rounding mode is allowed to be "dynamic" then the intrinsic needs to be IntrInaccessibleMemOnly (just like the constrained fp intrinsics). If we don't allow "dynamic" then it could be IntrNoMem.

Personally I have no interest in supporting "dynamic" so I would vote for disallowing it and making the intrinsic IntrNoMem.


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  https://reviews.llvm.org/D110579/new/

https://reviews.llvm.org/D110579