[AMDGPU][MC] Corrected parsing of op_sel* and neg_* modifiers

[dp]

Summary

See bug 41361: https://bugs.llvm.org/show_bug.cgi?id=41361

Note that this change also enables arbitrary constant expressions as operands of these modifiers (bug 40820).

[artem.tamazov]

Very good, thanks!

lib/Target/AMDGPU/AsmParser/AMDGPUAsmParser.cpp

public:
 
   OperandMatchResultTy parseIntWithPrefix(const char *Prefix, int64_t &Int);
 
   OperandMatchResultTy
   parseIntWithPrefix(const char *Prefix, OperandVector &Operands,
                      AMDGPUOperand::ImmTy ImmTy = AMDGPUOperand::ImmTyNone,
                      bool (*ConvertResult)(int64_t &) = nullptr);
 
-  OperandMatchResultTy parseOperandArrayWithPrefix(
-    const char *Prefix,
+  OperandMatchResultTy
+  parseOperandArrayWithPrefix(const char *Prefix,
                               OperandVector &Operands,
                               AMDGPUOperand::ImmTy ImmTy = AMDGPUOperand::ImmTyNone,
                               bool (*ConvertResult)(int64_t&) = nullptr);
 
   OperandMatchResultTy
   parseNamedBit(const char *Name, OperandVector &Operands,
                 AMDGPUOperand::ImmTy ImmTy = AMDGPUOperand::ImmTyNone);
   OperandMatchResultTy parseStringWithPrefix(StringRef Prefix,
                                              StringRef &Value);
 
   bool isModifier();
while (!getLexer().is(AsmToken::EndOfStatement)) {
 
     // Eat the comma or space if there is one.
     if (getLexer().is(AsmToken::Comma))
       Parser.Lex();
 
     switch (Res) {
       case MatchOperand_Success: break;
       case MatchOperand_ParseFail:
+        // FIXME: use real operand location rather than the current location.
         Error(getLexer().getLoc(), "failed parsing operand.");
         while (!getLexer().is(AsmToken::EndOfStatement)) {
           Parser.Lex();
         }
         return true;
       case MatchOperand_NoMatch:
+        // FIXME: use real operand location rather than the current location.
         Error(getLexer().getLoc(), "not a valid operand.");
         while (!getLexer().is(AsmToken::EndOfStatement)) {
           Parser.Lex();
         }
         return true;
     }
   }
 
AMDGPUAsmParser::parseIntWithPrefix(const char *Prefix, OperandVector &Operands,
   if (ConvertResult && !ConvertResult(Value)) {
     Error(S, "invalid " + StringRef(Prefix) + " value.");
   }
 
   Operands.push_back(AMDGPUOperand::CreateImm(this, Value, S, ImmTy));
   return MatchOperand_Success;
 }
 
-OperandMatchResultTy AMDGPUAsmParser::parseOperandArrayWithPrefix(
-  const char *Prefix,
+OperandMatchResultTy
+AMDGPUAsmParser::parseOperandArrayWithPrefix(const char *Prefix,
                                              OperandVector &Operands,
                                              AMDGPUOperand::ImmTy ImmTy,
                                              bool (*ConvertResult)(int64_t&)) {
-  StringRef Name = Parser.getTok().getString();
-  if (!Name.equals(Prefix))
+  SMLoc S = getLoc();
+  if (!trySkipId(Prefix, AsmToken::Colon))
     return MatchOperand_NoMatch;
 
-  Parser.Lex();
-  if (getLexer().isNot(AsmToken::Colon))
-    return MatchOperand_ParseFail;
-
-  Parser.Lex();
-  if (getLexer().isNot(AsmToken::LBrac))
+  if (!skipToken(AsmToken::LBrac, "expected a left square bracket"))
     return MatchOperand_ParseFail;
-  Parser.Lex();
 
   unsigned Val = 0;
-  SMLoc S = Parser.getTok().getLoc();
+  const unsigned MaxSize = 4;
 
   // FIXME: How to verify the number of elements matches the number of src
   // operands?
-  for (int I = 0; I < 4; ++I) {
-    if (I != 0) {
-      if (getLexer().is(AsmToken::RBrac))
-        break;
+  for (int I = 0; ; ++I) {
+    int64_t Op;
+    SMLoc Loc = getLoc();
+    if (!parseExpr(Op))
+      return MatchOperand_ParseFail;
 
-      if (getLexer().isNot(AsmToken::Comma))
-        return MatchOperand_ParseFail;
-      Parser.Lex();
+    if (Op != 0 && Op != 1) {
+      Error(Loc, "invalid " + StringRef(Prefix) + " value.");
     }
 
-    if (getLexer().isNot(AsmToken::Integer))
-      return MatchOperand_ParseFail;
+    Val |= (Op << I);
 
-    int64_t Op;
-    if (getParser().parseAbsoluteExpression(Op))
+    if (trySkipToken(AsmToken::RBrac))
+      break;
+
+    if (I + 1 == MaxSize) {
+      Error(getLoc(), "expected a closing square bracket");
       return MatchOperand_ParseFail;
+    }
 
-    if (Op != 0 && Op != 1)
+    if (!trySkipToken(AsmToken::Comma)) {
+      Error(getLoc(), "expected a comma");
       return MatchOperand_ParseFail;
-    Val |= (Op << I);
+    }
   }
 
-  Parser.Lex();
   Operands.push_back(AMDGPUOperand::CreateImm(this, Val, S, ImmTy));
   return MatchOperand_Success;
 }
 
 OperandMatchResultTy
 AMDGPUAsmParser::parseNamedBit(const char *Name, OperandVector &Operands,
                                AMDGPUOperand::ImmTy ImmTy) {
   int64_t Bit = 0;

test/MC/AMDGPU/dl-insts-err.s

 v_dot8_i32_i4 v0, v1, v2, v3
 // CHECK: error: instruction not supported on this GPU
 v_dot8_u32_u4 v0, v1, v2, v3
 
 //
 // Test invalid operands.
 //
 
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel:[0,0,0,0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 op_sel_hi:[0,0,0,0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 neg_lo:[0,0,0,0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_f32_f16 v0, v1, v2, v3 neg_hi:[0,0,0,0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel:[0,0,0,0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_i32_i16 v0, v1, v2, v3 op_sel_hi:[0,0,0,0,0]
 // FIXME-GFX906: error: invalid operand for instruction
 v_dot2_i32_i16 v0, v1, v2, v3 neg_lo:[0,0]
 // FIXME-GFX906: error: invalid operand for instruction
 v_dot2_i32_i16 v0, v1, v2, v3 neg_hi:[0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[,0]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel:[0,0,0,0,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid operand for instruction
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a left square bracket
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[,]
-// GFX906: error: failed parsing operand
+// GFX906: error: unknown token in expression
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[,0]
-// GFX906: error: failed parsing operand
+// GFX906: error: invalid op_sel_hi value
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[0,2]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[2,0]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[2,2]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[0,-1]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[-1,0]
 // GFX906: error: failed parsing operand
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[-1,-1]
-// GFX906: error: failed parsing operand
+// GFX906: error: expected a closing square bracket
 v_dot2_u32_u16 v0, v1, v2, v3 op_sel_hi:[0,0,0,0,0]
 // FIXME-GFX906: error: invalid operand for instruction
 v_dot2_u32_u16 v0, v1, v2, v3 neg_lo:[0,0]
 // FIXME-GFX906: error: invalid operand for instruction
 v_dot2_u32_u16 v0, v1, v2, v3 neg_hi:[0,0]
 
 //
 // Test regular modifiers.

test/MC/AMDGPU/expressions-gfx9.s

+// RUN: not llvm-mc -arch=amdgcn -mcpu=gfx900 -show-encoding %s | FileCheck %s --check-prefix=GFX9
+// RUN: not llvm-mc -arch=amdgcn -mcpu=gfx900 -show-encoding %s 2>&1 | FileCheck %s --check-prefix=NOGFX9
+
+//===----------------------------------------------------------------------===//
+// Relocatable expressions cannot be used with SDWA modifiers.
+//===----------------------------------------------------------------------===//
+
+v_mov_b32_sdwa v1, sext(u)
+// NOGFX9: error: expected an absolute expression
+
+//===----------------------------------------------------------------------===//
+// Constant expressions may be used with 'sext' modifier
+//===----------------------------------------------------------------------===//
+
+i1=1
+
+v_mov_b32_sdwa v1, sext(i1-2)
+// GFX9: v_mov_b32_sdwa v1, sext(-1) dst_sel:DWORD dst_unused:UNUSED_PRESERVE src0_sel:DWORD ; encoding: [0xf9,0x02,0x02,0x7e,0xc1,0x16,0x8e,0x00]
+
+v_mov_b32_sdwa v1, sext(-2+i1)
+// GFX9: v_mov_b32_sdwa v1, sext(-1) dst_sel:DWORD dst_unused:UNUSED_PRESERVE src0_sel:DWORD ; encoding: [0xf9,0x02,0x02,0x7e,0xc1,0x16,0x8e,0x00]
+
+//===----------------------------------------------------------------------===//
+// Constant expressions may be used with op_sel* and neg_* modifiers.
+//===----------------------------------------------------------------------===//
+
+v_pk_add_u16 v1, v2, v3 op_sel:[2-i1,i1-1]
+// GFX9: v_pk_add_u16 v1, v2, v3 op_sel:[1,0] ; encoding: [0x01,0x08,0x8a,0xd3,0x02,0x07,0x02,0x18]
+
+v_pk_add_u16 v1, v2, v3 neg_lo:[2-i1,i1-1]
+// GFX9: v_pk_add_u16 v1, v2, v3 neg_lo:[1,0] ; encoding: [0x01,0x00,0x8a,0xd3,0x02,0x07,0x02,0x38]

test/MC/AMDGPU/vop3p-err.s

 // RUN: not llvm-mc -arch=amdgcn -mcpu=gfx900 -show-encoding %s 2>&1 | FileCheck -check-prefix=GFX9 %s
 
-// GFX9: 31: error: failed parsing operand.
+// GFX9: 25: error: invalid operand for instruction
 v_pk_add_u16 v1, v2, v3 op_sel
 
-// GFX9: 32: error: failed parsing operand.
+// GFX9: 32: error: expected a left square bracket
 v_pk_add_u16 v1, v2, v3 op_sel:
 
-// GFX9: 33: error: failed parsing operand.
+// GFX9: 33: error: unknown token in expression
 v_pk_add_u16 v1, v2, v3 op_sel:[
 
-// GFX9: 33: error: failed parsing operand.
+// GFX9: 33: error: unknown token in expression
 v_pk_add_u16 v1, v2, v3 op_sel:[]
 
-// GFX9: 34: error: failed parsing operand.
+// GFX9: 33: error: unknown token in expression
 v_pk_add_u16 v1, v2, v3 op_sel:[,]
 
 // XXGFX9: 34: error: failed parsing operand.
 // v_pk_add_u16 v1, v2, v3 op_sel:[0]
 
-// GFX9: 35: error: failed parsing operand.
+// GFX9: 35: error: expected a comma
+v_pk_add_u16 v1, v2, v3 op_sel:[0 0]
+
+// GFX9: 35: error: unknown token in expression
 v_pk_add_u16 v1, v2, v3 op_sel:[0,]
 
-// XXGFX9: 36: error: failed parsing operand.
-// v_pk_add_u16 v1, v2, v3 op_sel:[,0]
+// GFX9: 33: error: unknown token in expression
+v_pk_add_u16 v1, v2, v3 op_sel:[,0]
+
+// GFX9: 42: error: expected a closing square bracket
+v_max3_f16 v5, v1, v2, v3 op_sel:[1,1,1,1,
+
+// GFX9: 42: error: expected a closing square bracket
+v_max3_f16 v5, v1, v2, v3 op_sel:[1,1,1,1[
+
+// GFX9: 43: error: expected a closing square bracket
+v_max3_f16 v5, v1, v2, v3 op_sel:[1,1,1,1 1
 
-// GFX9: 36: error: failed parsing operand.
+// GFX9: 35: error: invalid op_sel value.
 v_pk_add_u16 v1, v2, v3 op_sel:[0,2]
 
-// GFX9: 35: error: failed parsing operand.
+// GFX9: 33: error: invalid op_sel value.
 v_pk_add_u16 v1, v2, v3 op_sel:[2,0]
 
-// GFX9: 33: error: failed parsing operand.
+// GFX9: 33: error: invalid op_sel value.
 v_pk_add_u16 v1, v2, v3 op_sel:[-1,0]
 
-// GFX9: 35: error: failed parsing operand.
+// GFX9: 35: error: invalid op_sel value.
 v_pk_add_u16 v1, v2, v3 op_sel:[0,-1]
 
-// GFX9: 42: error: failed parsing operand.
+// GFX9: 40: error: expected a closing square bracket
 v_pk_add_u16 v1, v2, v3 op_sel:[0,0,0,0,0]
 
 // XXGFX9: invalid operand for instruction
 v_pk_add_u16 v1, v2, v3 neg_lo:[0,0]
 
 //
 // Regular modifiers on packed instructions
 //