[PATCH] D43151: [NVPTX] TblGen-ized lowering of WMMA intrinsics.

[Justin Lebar via Phabricator via llvm-commits]

jlebar added a comment.

Some comments, but mainly I'm just bewildered by tablegen.



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Comment at: llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp:3636
 
+bool NVPTXDAGToDAGISel::SelectADDRvar(SDNode *OpNode, SDValue Addr,
+                                      SDValue &Value) {
----------------
Is it worth having a comment on this one?


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Comment at: llvm/lib/Target/NVPTX/NVPTXIntrinsics.td:7420
                            string Type, NVPTXRegClass regclass,
-                           Operand SrcOp, int WithOffset, int WithStride>
-  : NVPTXInst<!if(!eq(Abc#Type,"cf16"),
-                  (outs regclass:$r0, regclass:$r1, regclass:$r2, regclass:$r3),
-                  (outs regclass:$r0, regclass:$r1, regclass:$r2, regclass:$r3,
-                         regclass:$r4, regclass:$r5, regclass:$r6, regclass:$r7)),
-              !if(WithStride,
-                  !if(WithOffset,
-                      (ins SrcOp:$src, i32imm:$offset, Int32Regs:$ldm),
-                      (ins SrcOp:$src, Int32Regs:$ldm)),
-                  !if(WithOffset,
-                      (ins SrcOp:$src, i32imm:$offset),
-                      (ins SrcOp:$src))),
-              "wmma.load."#Abc#".sync."#Layout#".m16n16k16"#Space#"." #Type# " \t"
+                           DAGOperand SrcOp, int WithStride>
+  : EmptyNVPTXInst, Requires<[hasPTX60, hasSM70]> {
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Can we make WithStride a bool, or is that not supported?


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Comment at: llvm/lib/Target/NVPTX/NVPTXIntrinsics.td:7426
+                                   # !subst(".","_",Space)
+                                   # !if(WithStride,"_stride", ""));
+  dag OutsR03 = (outs regclass:$r0, regclass:$r1, regclass:$r2, regclass:$r3);
----------------
It's sort of a nit, but: I think I see what you're trying to do with the alignment of `#` under the paren, but it doesn't totally work for me, especially when we add a space *after* the `#`.

Maybe you could just pull the `#`s up onto the line above?  Then we don't have any of these issues.


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Comment at: llvm/lib/Target/NVPTX/NVPTXIntrinsics.td:7505
+
+  //let InOperandList = InsR;
+  let AsmString = "wmma.store.d.sync."#Layout#".m16n16k16"#Space#"." #Type# " \t"
----------------
Dead code?


https://reviews.llvm.org/D43151