[AMDGPU][MC][GFX11] Add validation of constant bus limitations for VOPD

[rampitec]

LGTM with a nit.

llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

3503

Could you please move 'continue' onto a separate line?

[dp]

llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

3503

Sure, thanks!

llvm/lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

AMDGPUAsmParser::validateConstantBusLimitations(const MCInst &Inst,
                                                 const OperandVector &Operands) {
   const unsigned Opcode = Inst.getOpcode();
   const MCInstrDesc &Desc = MII.get(Opcode);
   unsigned LastSGPR = AMDGPU::NoRegister;
   unsigned ConstantBusUseCount = 0;
   unsigned NumLiterals = 0;
   unsigned LiteralSize;
 
-  if (Desc.TSFlags &
-      (SIInstrFlags::VOPC |
-       SIInstrFlags::VOP1 | SIInstrFlags::VOP2 |
-       SIInstrFlags::VOP3 | SIInstrFlags::VOP3P |
-       SIInstrFlags::SDWA)) {
-    // Check special imm operands (used by madmk, etc)
-    if (AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::imm) != -1) {
-      ++NumLiterals;
-      LiteralSize = 4;
-    }
+  if (!(Desc.TSFlags &
+        (SIInstrFlags::VOPC | SIInstrFlags::VOP1 | SIInstrFlags::VOP2 |
+         SIInstrFlags::VOP3 | SIInstrFlags::VOP3P | SIInstrFlags::SDWA)) &&
+      !isVOPD(Opcode))
+    return true;
+
 
-    SmallDenseSet<unsigned> SGPRsUsed;
-    unsigned SGPRUsed = findImplicitSGPRReadInVOP(Inst);
-    if (SGPRUsed != AMDGPU::NoRegister) {
-      SGPRsUsed.insert(SGPRUsed);
-      ++ConstantBusUseCount;
-    }
 
-    const int Src0Idx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::src0);
-    const int Src1Idx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::src1);
-    const int Src2Idx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::src2);
-
-    const int OpIndices[] = { Src0Idx, Src1Idx, Src2Idx };
+  OperandIndices OpIndices = getSrcOperandIndices(Opcode);
 
-    for (int OpIdx : OpIndices) {
-      if (OpIdx == -1) break;
+    if (OpIdx == -1) continue;
 
-      const MCOperand &MO = Inst.getOperand(OpIdx);
-      if (usesConstantBus(Inst, OpIdx)) {
-        if (MO.isReg()) {
-          LastSGPR = mc2PseudoReg(MO.getReg());
-          // Pairs of registers with a partial intersections like these
-          //   s0, s[0:1]
-          //   flat_scratch_lo, flat_scratch
-          //   flat_scratch_lo, flat_scratch_hi
-          // are theoretically valid but they are disabled anyway.
-          // Note that this code mimics SIInstrInfo::verifyInstruction
-          if (SGPRsUsed.insert(LastSGPR).second) {
-            ++ConstantBusUseCount;
-          }
-        } else { // Expression or a literal
 
-          if (Desc.OpInfo[OpIdx].OperandType == MCOI::OPERAND_IMMEDIATE)
-            continue; // special operand like VINTERP attr_chan
 
-          // An instruction may use only one literal.
-          // This has been validated on the previous step.
-          // See validateVOPLiteral.
-          // This literal may be used as more than one operand.
-          // If all these operands are of the same size,
-          // this literal counts as one scalar value.
-          // Otherwise it counts as 2 scalar values.
-          // See "GFX10 Shader Programming", section 3.6.2.3.
 
-          unsigned Size = AMDGPU::getOperandSize(Desc, OpIdx);
-          if (Size < 4) Size = 4;
 
-          if (NumLiterals == 0) {
-            NumLiterals = 1;
-            LiteralSize = Size;
-          } else if (LiteralSize != Size) {
-            NumLiterals = 2;
-          }
-        }
-      }
-    }
-  }
   ConstantBusUseCount += NumLiterals;
 
   if (ConstantBusUseCount <= getConstantBusLimit(Opcode))
     return true;
 
   SMLoc LitLoc = getLitLoc(Operands);
   SMLoc RegLoc = getRegLoc(LastSGPR, Operands);
   SMLoc Loc = (LitLoc.getPointer() < RegLoc.getPointer()) ? RegLoc : LitLoc;

llvm/test/MC/AMDGPU/gfx11_asm_vopd_errs.s

 // When 2 different literals are specified and all literals are KImm,
 // show the location of the last KImm literal.
 //===----------------------------------------------------------------------===//
 
 v_dual_fmamk_f32    v122, s0, 0xdeadbeef, v161   ::  v_dual_fmamk_f32  v123, s0, 0x1234, v162
 // GFX11: error: only one literal operand is allowed
 // GFX11-NEXT:{{^}}v_dual_fmamk_f32    v122, s0, 0xdeadbeef, v161   ::  v_dual_fmamk_f32  v123, s0, 0x1234, v162
 // GFX11-NEXT:{{^}}                                                                                 ^
+
+//===----------------------------------------------------------------------===//
+// A VOPD instruction cannot use more than 2 scalar operands
+//===----------------------------------------------------------------------===//
+
+// 2 different SGPRs + LITERAL
+
+v_dual_fmaak_f32    v122, s74, v161, 2.741       ::  v_dual_and_b32       v247, s75, v98
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_fmaak_f32    v122, s74, v161, 2.741       ::  v_dual_and_b32       v247, s75, v98
+// GFX11-NEXT:{{^}}                                                                                ^
+
+v_dual_mov_b32      v247, s73                    ::  v_dual_fmaak_f32     v122, s74, v161, 2.741
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_mov_b32      v247, s73                    ::  v_dual_fmaak_f32     v122, s74, v161, 2.741
+// GFX11-NEXT:{{^}}                                                                                ^
+
+v_dual_fmamk_f32    v122, s0, 0xbabe, v161       ::  v_dual_fmamk_f32     v123, s1, 0xbabe, v162
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_fmamk_f32    v122, s0, 0xbabe, v161       ::  v_dual_fmamk_f32     v123, s1, 0xbabe, v162
+// GFX11-NEXT:{{^}}                                                                                ^
+
+// 2 different SGPRs + VCC
+
+v_dual_add_f32      v255, s1, v2                 ::  v_dual_cndmask_b32   v6, s2, v3
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_add_f32      v255, s1, v2                 ::  v_dual_cndmask_b32   v6, s2, v3
+// GFX11-NEXT:{{^}}                                                                              ^
+
+v_dual_cndmask_b32   v6, s1, v3                  ::  v_dual_add_f32       v255, s2, v2
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_cndmask_b32   v6, s1, v3                  ::  v_dual_add_f32       v255, s2, v2
+// GFX11-NEXT:{{^}}                                                                                ^
+
+v_dual_cndmask_b32  v255, s1, v2                 ::  v_dual_cndmask_b32   v6, s2, v3
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_cndmask_b32  v255, s1, v2                 ::  v_dual_cndmask_b32   v6, s2, v3
+// GFX11-NEXT:{{^}}                                                                              ^
+
+// SGPR + LITERAL + VCC
+
+v_dual_cndmask_b32  v255, s1, v2                 ::  v_dual_mov_b32       v254, 0xbabe
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_cndmask_b32  v255, s1, v2                 ::  v_dual_mov_b32       v254, 0xbabe
+// GFX11-NEXT:{{^}}                                                                                ^
+
+v_dual_cndmask_b32  v255, 0xbabe, v2             ::  v_dual_mov_b32       v254, s1
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_cndmask_b32  v255, 0xbabe, v2             ::  v_dual_mov_b32       v254, s1
+// GFX11-NEXT:{{^}}                                                                                ^
+
+v_dual_cndmask_b32  v255, s3, v2                 ::  v_dual_fmamk_f32     v254, v1, 0xbabe, v162
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_cndmask_b32  v255, s3, v2                 ::  v_dual_fmamk_f32     v254, v1, 0xbabe, v162
+// GFX11-NEXT:{{^}}                          ^
+
+v_dual_cndmask_b32  v255, v1, v2                 ::  v_dual_fmamk_f32     v254, s3, 0xbabe, v162
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_cndmask_b32  v255, v1, v2                 ::  v_dual_fmamk_f32     v254, s3, 0xbabe, v162
+// GFX11-NEXT:{{^}}                                                                                ^
+
+// SGPR + VCC + VCC_LO
+// This is a special case because implicit VCC operand has 64 bit size.
+// SP3 does not accept this instruction as well.
+
+v_dual_add_f32      v255, vcc_lo, v2             ::  v_dual_cndmask_b32   v6, s1, v3
+// GFX11: error: invalid operand (violates constant bus restrictions)
+// GFX11-NEXT:{{^}}v_dual_add_f32      v255, vcc_lo, v2             ::  v_dual_cndmask_b32   v6, s1, v3
+// GFX11-NEXT:{{^}}                                                                              ^

llvm/test/MC/AMDGPU/gfx11_asm_vopd_features.s

 
 v_dual_fmamk_f32    v122, v74, 0xfe0b, v162      ::  v_dual_dot2acc_f32_f16  v247, 0xfe0b, v99
 // GFX11: encoding: [0x4a,0x45,0x99,0xc8,0xff,0xc6,0xf6,0x7a,0x0b,0xfe,0x00,0x00]
 
 // KIMM*2
 
 v_dual_fmamk_f32    v122, 0xdeadbeef, 0xdeadbeef, v161 ::  v_dual_fmamk_f32  v123, 0xdeadbeef, 0xdeadbeef, v162
 // GFX11: encoding: [0xff,0x42,0x85,0xc8,0xff,0x44,0x7b,0x7a,0xef,0xbe,0xad,0xde]
+
+//===----------------------------------------------------------------------===//
+// A VOPD instruction can use 2 scalar operands,
+// but implicit VCC must be counted in.
+//===----------------------------------------------------------------------===//
+
+// 2 different SGPRs
+
+v_dual_mul_f32      v0, s1, v2                   ::  v_dual_mul_f32       v3, s4, v5
+// GFX11: encoding: [0x01,0x04,0xc6,0xc8,0x04,0x0a,0x02,0x00]
+
+// SGPR + LITERAL
+
+v_dual_fmaak_f32    v122, s74, v161, 2.741       ::  v_dual_and_b32       v247, v160, v98
+// GFX11: encoding: [0x4a,0x42,0x65,0xc8,0xa0,0xc5,0xf6,0x7a,0x8b,0x6c,0x2f,0x40]
+
+v_dual_mov_b32      v247, v160                   ::  v_dual_fmaak_f32     v122, s74, v161, 2.741
+// GFX11: encoding: [0xa0,0x01,0x02,0xca,0x4a,0x42,0x7b,0xf7,0x8b,0x6c,0x2f,0x40]
+
+// SGPR*2 + LITERAL
+
+v_dual_fmaak_f32    v122, s74, v161, 2.741       ::  v_dual_and_b32       v247, s74, v98
+// GFX11: encoding: [0x4a,0x42,0x65,0xc8,0x4a,0xc4,0xf6,0x7a,0x8b,0x6c,0x2f,0x40]
+
+// SGPR + LITERAL*2
+
+v_dual_fmaak_f32    v122, s74, v161, 2.741       ::  v_dual_fmamk_f32     v3, v6, 2.741, v1
+// GFX11: encoding: [0x4a,0x42,0x45,0xc8,0x06,0x03,0x02,0x7a,0x8b,0x6c,0x2f,0x40]
+
+// SGPR*2 + LITERAL*2
+
+v_dual_fmaak_f32    v122, s74, v161, 2.741       ::  v_dual_fmamk_f32     v3, s74, 2.741, v1
+// GFX11: encoding: [0x4a,0x42,0x45,0xc8,0x4a,0x02,0x02,0x7a,0x8b,0x6c,0x2f,0x40]
+
+// LITERAL + VCC
+
+v_dual_fmaak_f32    v122, v0, v161, 2.741       ::  v_dual_cndmask_b32   v1, v2, v3
+// GFX11: encoding: [0x00,0x43,0x53,0xc8,0x02,0x07,0x00,0x7a,0x8b,0x6c,0x2f,0x40]
+
+// LITERAL*2 + VCC
+
+v_dual_fmaak_f32    v122, v0, v161, 2.741       ::  v_dual_cndmask_b32   v1, 2.741, v3
+// GFX11: encoding: [0x00,0x43,0x53,0xc8,0xff,0x06,0x00,0x7a,0x8b,0x6c,0x2f,0x40]
+
+// LITERAL*2 + VCC*2
+
+v_dual_cndmask_b32  v255, 0xbabe, v2             ::  v_dual_cndmask_b32   v6, 0xbabe, v3
+// GFX11: encoding: [0xff,0x04,0x52,0xca,0xff,0x06,0x06,0xff,0xbe,0xba,0x00,0x00]
+
+// SGPR*2 + VCC
+
+v_dual_add_f32      v255, s105, v2               ::  v_dual_cndmask_b32   v6, s105, v3
+// GFX11: encoding: [0x69,0x04,0x12,0xc9,0x69,0x06,0x06,0xff]
+
+// SGPR*2 + VCC*2
+
+v_dual_cndmask_b32  v255, s1, v2                 ::  v_dual_cndmask_b32   v6, s1, v3
+// GFX11: encoding: [0x01,0x04,0x52,0xca,0x01,0x06,0x06,0xff]
+
+// VCC*2
+
+v_dual_add_f32      v255, vcc_lo, v2             ::  v_dual_cndmask_b32   v6, v1, v3
+// GFX11: encoding: [0x6a,0x04,0x12,0xc9,0x01,0x07,0x06,0xff]