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gromer (Geoffrey Romer)
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Jan 24 2018, 9:36 AM (46 w, 6 d)

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Sep 21 2018

gromer added a comment to D51812: Simplify CheckFallThroughForBody.

OK, the diffs are now un-borked. Sorry for the flailing incompetence.

Sep 21 2018, 2:02 PM
gromer updated the diff for D51812: Simplify CheckFallThroughForBody.
Sep 21 2018, 2:00 PM
gromer updated the diff for D51812: Simplify CheckFallThroughForBody.
Sep 21 2018, 1:43 PM
gromer added inline comments to D51812: Simplify CheckFallThroughForBody.
Sep 21 2018, 11:31 AM
gromer updated the diff for D51812: Simplify CheckFallThroughForBody.
Sep 21 2018, 11:22 AM

Sep 7 2018

gromer created D51812: Simplify CheckFallThroughForBody.
Sep 7 2018, 1:50 PM

Jan 26 2018

gromer added a comment to D41761: Introduce llvm.nospeculateload intrinsic.

Do we need to explicitly prohibit it in LangRef so that future transformations don't start understanding too much about what speculationsafeload does?

Prohibit what, exactly? According to current LangRef rules, it's legal to introduce a dead load to an arbitrary pointer (even if the compiler can't prove it's dereferencable).

Jan 26 2018, 6:41 PM
gromer added a comment to D41761: Introduce llvm.nospeculateload intrinsic.
template <typename T, typename... ZeroArgs>
bool IsPointerInRange(T*& pointer, T* begin, T* end, ZeroArgs... args);

This function returns whether pointer is between begin and end, and also guarantees that if the function returns false, then any speculative execution which assumes it to be true will treat pointer and args... as zero (all ZeroArgs must be integers or pointers). Notice that this API allows the optimizer to hoist loads past the branch, so long as the loads don't depend on pointer or args...; I'm not sure if that's true of nospeculateload or SecureBoundedOffset.

Jan 26 2018, 2:13 PM
gromer added a comment to D41761: Introduce llvm.nospeculateload intrinsic.

(I hope you can bear with me while I come up to speed; I understand there's some time pressure here, so I'm erring on the side of speaking sooner)

Jan 26 2018, 1:19 PM