[TableGen] Validate the shift amount for !srl, !shl, and !sra operators. (#132492)

The C operator has undefined behavior for out of bounds shifts so we
should check this.

Author: topperc

llvm/lib/TableGen/Record.cpp

@@ -1564,9 +1564,24 @@ const Init *BinOpInit::Fold(const Record *CurRec) const {
       case AND: Result = LHSv & RHSv; break;
       case OR:  Result = LHSv | RHSv; break;
       case XOR: Result = LHSv ^ RHSv; break;
-      case SHL: Result = (uint64_t)LHSv << (uint64_t)RHSv; break;
-      case SRA: Result = LHSv >> RHSv; break;
-      case SRL: Result = (uint64_t)LHSv >> (uint64_t)RHSv; break;
+      case SHL:
+        if (RHSv < 0 || RHSv >= 64)
+          PrintFatalError(CurRec->getLoc(),
+                          "Illegal operation: out of bounds shift");
+        Result = (uint64_t)LHSv << (uint64_t)RHSv;
+        break;
+      case SRA:
+        if (RHSv < 0 || RHSv >= 64)
+          PrintFatalError(CurRec->getLoc(),
+                          "Illegal operation: out of bounds shift");
+        Result = LHSv >> (uint64_t)RHSv;
+        break;
+      case SRL:
+        if (RHSv < 0 || RHSv >= 64)
+          PrintFatalError(CurRec->getLoc(),
+                          "Illegal operation: out of bounds shift");
+        Result = (uint64_t)LHSv >> (uint64_t)RHSv;
+        break;
       }
       return IntInit::get(getRecordKeeper(), Result);
     }

llvm/test/TableGen/math.td

@@ -3,6 +3,9 @@
 // RUN: not llvm-tblgen -DERROR2 %s 2>&1 | FileCheck --check-prefix=ERROR2 %s
 // RUN: not llvm-tblgen -DERROR3 %s 2>&1 | FileCheck --check-prefix=ERROR3 %s
 // RUN: not llvm-tblgen -DERROR4 %s 2>&1 | FileCheck --check-prefix=ERROR4 %s
+// RUN: not llvm-tblgen -DERROR5 %s 2>&1 | FileCheck --check-prefix=ERROR5 %s
+// RUN: not llvm-tblgen -DERROR6 %s 2>&1 | FileCheck --check-prefix=ERROR6 %s
+// RUN: not llvm-tblgen -DERROR7 %s 2>&1 | FileCheck --check-prefix=ERROR7 %s
 // XFAIL: vg_leak
 
 // CHECK: def shifts
@@ -143,3 +146,18 @@ def v954 : Int<!logtwo(-1)>;
 // CHECK: def vneg
 // CHECK: Value = -2
 def vneg : Int<!sub(v925.Value, 927)>;
+
+#ifdef ERROR5
+// ERROR5: error: Illegal operation: out of bounds shift
+def vshl_neg : Int<!shl(1, -1)>;
+#endif
+
+#ifdef ERROR6
+// ERROR6: error: Illegal operation: out of bounds shift
+def vsra_large : Int<!sra(1, 64)>;
+#endif
+
+#ifdef ERROR7
+// ERROR7: error: Illegal operation: out of bounds shift
+def vsrl_large : Int<!srl(1, 100)>;
+#endif