[PATCH] D31874: AMDGPU: Switch aperture queries to use aperture registers instead of s_getreg_b32

[Konstantin Zhuravlyov via Phabricator via llvm-commits]

kzhuravl added inline comments.


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Comment at: lib/Target/AMDGPU/SIISelLowering.cpp:2357-2358
+        DAG, &AMDGPU::SReg_64RegClass, ApertureRegNo, MVT::i64);
+    SDValue Aperture = SDValue(
+        DAG.getMachineNode(AMDGPU::S_MOV_B64, DL, MVT::i64, ApertureReg), 0);
+    return DAG.getTargetExtractSubreg(AMDGPU::sub1, DL, MVT::i32, Aperture);
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arsenm wrote:
> arsenm wrote:
> > You shouldn't emit a raw mov here, this should be a CopyFromReg
> Also this is extracting the sub register when you can just directly copy from the sub register?
Did you mean copy directly from the sub register of src_*_base? If yes, then I do not think it is possible, as it is an 64 bit inline constant, and there are no inline constants for _lo and _hi parts. If no, can you elaborate?

Thanks.


https://reviews.llvm.org/D31874