[PATCH] D28527: Check for register clobbers when merging a vreg live range with a reserved physreg in RegisterCoalescer.

[Quentin Colombet via Phabricator via llvm-commits]

qcolombet added inline comments.


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Comment at: test/CodeGen/AArch64/regcoal-physreg.mir:77
+
+    ; Need a def of x18 so that it's not deduced as "constant".
+    %x18 = COPY %xzr
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That sounds like a bug to me.
I would have expected the constant attribute to be decided by the target, i.e., not something that depends on the presence of a definition.

Could you investigate please?


https://reviews.llvm.org/D28527