craig.topper added a comment. In D126461#3596761 <https://reviews.llvm.org/D126461#3596761>, @reames wrote:
> Despite the comments above, the purpose of this patch remains unclear. > > Per the draft spec, the relevant wording is: > "These instructions execute as a regular load except that they will only take > a trap caused by a synchronous exception > on element 0. If element 0 raises an exception, vl is not modied, and the > trap is taken. If an element > 0 raises an > exception, the corresponding trap is not taken, and the vector length vl is > reduced to the index of the element that would > have raised an exception." > > Working through the scenario in this patch with the destination being null, > the expected result is for a trap to be generated (provided null is unmapped > of course), and VL not to be modified. In order for this change to make any > difference in runtime behavior, the value passed must be null (or otherwise > guaranteed to fault). It seems very odd to me that we are modifying code > which only runs after an instruction which is guaranteed to fault. Is there > an assumed runtime here which is e.g. restarting execution? `dst` in the patch description is not the pointer being loaded, it's the pointer of where to store the new_vl. That is only thing being checked for null in this patch. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D126461/new/ https://reviews.llvm.org/D126461 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
