[RISCV] Add register group overlap checks to the assembler for vector indexed segment load (#184963)

f7ca74f600
has added basic check for register overlap.
Furthermore, we need to add extra check for register group overlap since
more registers will be occupied in segment load.

llvm/lib/Target/RISCV/AsmParser/RISCVAsmParser.cpp

@@ -3802,6 +3802,76 @@ std::unique_ptr<RISCVOperand> RISCVAsmParser::defaultFRMArgLegacyOp() const {
                                     llvm::SMLoc());
 }
 
+static unsigned getNFforLXSEG(unsigned Opcode) {
+  switch (Opcode) {
+  default:
+    return 1;
+  case RISCV::VLOXSEG2EI8_V:
+  case RISCV::VLOXSEG2EI16_V:
+  case RISCV::VLOXSEG2EI32_V:
+  case RISCV::VLOXSEG2EI64_V:
+  case RISCV::VLUXSEG2EI8_V:
+  case RISCV::VLUXSEG2EI16_V:
+  case RISCV::VLUXSEG2EI32_V:
+  case RISCV::VLUXSEG2EI64_V:
+    return 2;
+  case RISCV::VLOXSEG3EI8_V:
+  case RISCV::VLOXSEG3EI16_V:
+  case RISCV::VLOXSEG3EI32_V:
+  case RISCV::VLOXSEG3EI64_V:
+  case RISCV::VLUXSEG3EI8_V:
+  case RISCV::VLUXSEG3EI16_V:
+  case RISCV::VLUXSEG3EI32_V:
+  case RISCV::VLUXSEG3EI64_V:
+    return 3;
+  case RISCV::VLOXSEG4EI8_V:
+  case RISCV::VLOXSEG4EI16_V:
+  case RISCV::VLOXSEG4EI32_V:
+  case RISCV::VLOXSEG4EI64_V:
+  case RISCV::VLUXSEG4EI8_V:
+  case RISCV::VLUXSEG4EI16_V:
+  case RISCV::VLUXSEG4EI32_V:
+  case RISCV::VLUXSEG4EI64_V:
+    return 4;
+  case RISCV::VLOXSEG5EI8_V:
+  case RISCV::VLOXSEG5EI16_V:
+  case RISCV::VLOXSEG5EI32_V:
+  case RISCV::VLOXSEG5EI64_V:
+  case RISCV::VLUXSEG5EI8_V:
+  case RISCV::VLUXSEG5EI16_V:
+  case RISCV::VLUXSEG5EI32_V:
+  case RISCV::VLUXSEG5EI64_V:
+    return 5;
+  case RISCV::VLOXSEG6EI8_V:
+  case RISCV::VLOXSEG6EI16_V:
+  case RISCV::VLOXSEG6EI32_V:
+  case RISCV::VLOXSEG6EI64_V:
+  case RISCV::VLUXSEG6EI8_V:
+  case RISCV::VLUXSEG6EI16_V:
+  case RISCV::VLUXSEG6EI32_V:
+  case RISCV::VLUXSEG6EI64_V:
+    return 6;
+  case RISCV::VLOXSEG7EI8_V:
+  case RISCV::VLOXSEG7EI16_V:
+  case RISCV::VLOXSEG7EI32_V:
+  case RISCV::VLOXSEG7EI64_V:
+  case RISCV::VLUXSEG7EI8_V:
+  case RISCV::VLUXSEG7EI16_V:
+  case RISCV::VLUXSEG7EI32_V:
+  case RISCV::VLUXSEG7EI64_V:
+    return 7;
+  case RISCV::VLOXSEG8EI8_V:
+  case RISCV::VLOXSEG8EI16_V:
+  case RISCV::VLOXSEG8EI32_V:
+  case RISCV::VLOXSEG8EI64_V:
+  case RISCV::VLUXSEG8EI8_V:
+  case RISCV::VLUXSEG8EI16_V:
+  case RISCV::VLUXSEG8EI32_V:
+  case RISCV::VLUXSEG8EI64_V:
+    return 8;
+  }
+}
+
 unsigned getLMULFromVectorRegister(MCRegister Reg) {
   if (RISCVMCRegisterClasses[RISCV::VRM2RegClassID].contains(Reg))
     return 2;
@@ -3874,7 +3944,8 @@ bool RISCVAsmParser::validateInstruction(MCInst &Inst,
     assert(VS2Idx >= 0 && "No vs2 operand?");
     unsigned CheckEncoding =
         RI->getEncodingValue(Inst.getOperand(VS2Idx).getReg());
-    for (unsigned i = 0; i < Lmul; i++) {
+    unsigned NF = getNFforLXSEG(Opcode);
+    for (unsigned i = 0; i < std::max(NF, Lmul); i++) {
       if ((DestEncoding + i) == CheckEncoding)
         return Error(Loc, "the destination vector register group cannot overlap"
                           " the source vector register group");

llvm/test/MC/RISCV/rvv/zvlsseg-invalid.s

@@ -4,6 +4,34 @@
 vluxseg2ei8.v v8, (a0), v8, v0.t
 # CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
 # CHECK-ERROR-LABEL: vluxseg2ei8.v v8, (a0), v8, v0.t
+
+vluxseg2ei8.v v8, (a0), v9, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg2ei8.v v8, (a0), v9, v0.t
+ 
+vluxseg3ei8.v v8, (a0), v10, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg3ei8.v v8, (a0), v10, v0.t
+ 
+vluxseg4ei8.v v8, (a0), v11, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg4ei8.v v8, (a0), v11, v0.t
+ 
+vluxseg5ei8.v v8, (a0), v12, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg5ei8.v v8, (a0), v12, v0.t
+ 
+vluxseg6ei8.v v8, (a0), v13, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg6ei8.v v8, (a0), v13, v0.t
+ 
+vluxseg7ei8.v v8, (a0), v14, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg7ei8.v v8, (a0), v14, v0.t
+ 
+vluxseg8ei8.v v8, (a0), v15, v0.t
+# CHECK-ERROR: the destination vector register group cannot overlap the source vector register group
+# CHECK-ERROR-LABEL: vluxseg8ei8.v v8, (a0), v15, v0.t
  
 vluxseg2ei8.v v8, (a0), v8
 # CHECK-ERROR: the destination vector register group cannot overlap the source vector register group