[PATCH] D118089: [AMDGPU] Validate dst and src2 non-overlapping restriction in asm

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp:3643
+
+  if (RUCount <= 8) // 4 VGPRs or less
+    return true;
----------------
arsenm wrote:
> rampitec wrote:
> > arsenm wrote:
> > > Can't you get the width directly from the operand register class without making an assumption about the number of register units?
> > I cannot get RC itself.
> It's in the MCInstrDesc which you have
It is not:
```
 struct MCRegisterDesc {
   uint32_t Name;      // Printable name for the reg (for debugging)
   uint32_t SubRegs;   // Sub-register set, described above
   uint32_t SuperRegs; // Super-register set, described above
  
   // Offset into MCRI::SubRegIndices of a list of sub-register indices for each
   // sub-register in SubRegs.
   uint32_t SubRegIndices;
  
   // RegUnits - Points to the list of register units. The low 4 bits holds the
   // Scale, the high bits hold an offset into DiffLists. See MCRegUnitIterator.
   uint32_t RegUnits;
  
   /// Index into list with lane mask sequences. The sequence contains a lanemask
   /// for every register unit.
   uint16_t RegUnitLaneMasks;
 };
```
I guess because is a register can belong to different classes.


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  https://reviews.llvm.org/D118089/new/

https://reviews.llvm.org/D118089