[AMDGPU] Remove Base_MUBUF_Real_Atomic_gfx11. NFC.

[jayfoad]

This class only existed to set the dlc bit for GFX11 atomics. It is
simpler to set dlc for all loads/stores/atomics in the base class.

[llvmbot]

@llvm/pr-subscribers-backend-amdgpu

Author: Jay Foad (jayfoad)

Changes

This class only existed to set the dlc bit for GFX11 atomics. It is
simpler to set dlc for all loads/stores/atomics in the base class.

---

Full diff: https://github.com/llvm/llvm-project/pull/83994.diff

1 Files Affected:

• (modified) llvm/lib/Target/AMDGPU/BUFInstructions.td (+3-8)

diff --git a/llvm/lib/Target/AMDGPU/BUFInstructions.td b/llvm/lib/Target/AMDGPU/BUFInstructions.td
index a2ff56d68218cd..20e91da4995b7b 100644
--- a/llvm/lib/Target/AMDGPU/BUFInstructions.td
+++ b/llvm/lib/Target/AMDGPU/BUFInstructions.td
@@ -2301,7 +2301,8 @@ class MUBUF_Real_gfx11<bits<8> op, MUBUF_Pseudo ps,
                        string real_name = ps.Mnemonic> :
   Base_MUBUF_Real_gfx6_gfx7_gfx10_gfx11<ps, SIEncodingFamily.GFX11, real_name> {
   let Inst{12}    = !if(ps.has_slc, cpol{CPolBit.SLC}, ?);
-  let Inst{13}    = !if(ps.has_dlc, cpol{CPolBit.DLC}, ps.dlc_value);
+  // In GFX11 dlc is applicable to all loads/stores/atomics.
+  let Inst{13}    = !if(!or(ps.mayLoad, ps.mayStore), cpol{CPolBit.DLC}, ps.dlc_value);
   let Inst{14}    = !if(ps.has_glc, cpol{CPolBit.GLC}, ps.glc_value);
   let Inst{25-18} = op;
   let Inst{53}    = ps.tfe;
@@ -2311,12 +2312,6 @@ class MUBUF_Real_gfx11<bits<8> op, MUBUF_Pseudo ps,
   let DecoderNamespace = "GFX11";
 }
 
-class Base_MUBUF_Real_Atomic_gfx11<bits<8> op, MUBUF_Pseudo ps,
-                                   string real_name> :
-  MUBUF_Real_gfx11<op, ps, real_name> {
-  let Inst{13} = cpol{CPolBit.DLC};
-}
-
 class Base_MUBUF_Real_gfx6_gfx7_gfx10<bits<7> op, MUBUF_Pseudo ps, int ef> :
   Base_MUBUF_Real_gfx6_gfx7_gfx10_gfx11<ps, ef> {
   let Inst{12}    = ps.offen;
@@ -2499,7 +2494,7 @@ multiclass MUBUF_Real_AllAddr_gfx11_gfx12_Renamed<bits<8> op, string real_name>
 
 class MUBUF_Real_Atomic_gfx11_impl<bits<8> op, string ps_name,
                                    string real_name> :
-  Base_MUBUF_Real_Atomic_gfx11<op, !cast<MUBUF_Pseudo>(ps_name), real_name>;
+  MUBUF_Real_gfx11<op, !cast<MUBUF_Pseudo>(ps_name), real_name>;
 
 class MUBUF_Real_Atomic_gfx12_impl<bits<8> op, string ps_name,
                                    string real_name> :

[jayfoad]

This could perhaps use some further cleanup. The confusion is that has_dlc is a field in the pseudo, but in fact whether an instruction "has dlc" is different on different subtargets:

• before GFX11 only loads and stores have dlc
• in GFX11, atomics also have dlc (but invalidates still do not)

[kosarev]

Looks like the next thing to get rid of?

[jayfoad]

Yes, I am working on a larger patch to remove some useless *_impl classes.