string PostEncoderMethod = "";
string DecoderMethod = "";
+ // Is the instruction decoder method able to completely determine if the
+ // given instruction is valid or not. If the TableGen definition of the
+ // instruction specifies bitpattern A??B where A and B are static bits, the
+ // hasCompleteDecoder flag says whether the decoder method fully handles the
+ // ?? space, i.e. if it is a final arbiter for the instruction validity.
+ // If not then the decoder attempts to continue decoding when the decoder
+ // method fails.
+ //
+ // This allows to handle situations where the encoding is not fully
+ // orthogonal. Example:
+ // * InstA with bitpattern 0b0000????,
+ // * InstB with bitpattern 0b000000?? but the associated decoder method
+ // DecodeInstB() returns Fail when ?? is 0b00 or 0b11.
+ //
+ // The decoder tries to decode a bitpattern that matches both InstA and
+ // InstB bitpatterns first as InstB (because it is the most specific
+ // encoding). In the default case (hasCompleteDecoder = 1), when
+ // DecodeInstB() returns Fail the bitpattern gets rejected. By setting
+ // hasCompleteDecoder = 0 in InstB, the decoder is informed that
+ // DecodeInstB() is not able to determine if all possible values of ?? are
+ // valid or not. If DecodeInstB() returns Fail the decoder will attempt to
+ // decode the bitpattern as InstA too.
+ bit hasCompleteDecoder = 1;
+
/// Target-specific flags. This becomes the TSFlags field in TargetInstrDesc.
bits<64> TSFlags = 0;
string PrintMethod = "printOperand";
string EncoderMethod = "";
string DecoderMethod = "";
+ bit hasCompleteDecoder = 1;
string OperandType = "OPERAND_UNKNOWN";
dag MIOperandInfo = (ops);
let hasSideEffects = 0;
bit isPseudo = 1;
}
-def FRAME_ALLOC : Instruction {
+def LOCAL_ESCAPE : Instruction {
// This instruction is really just a label. It has to be part of the chain so
// that it doesn't get dropped from the DAG, but it produces nothing and has
// no side effects.
let hasSideEffects = 0;
let hasCtrlDep = 1;
}
+def FAULTING_LOAD_OP : Instruction {
+ let OutOperandList = (outs unknown:$dst);
+ let InOperandList = (ins variable_ops);
+ let usesCustomInserter = 1;
+ let mayLoad = 1;
+}
}
//===----------------------------------------------------------------------===//
// Predicates - Predicates that must be true for this to match.
list<Predicate> Predicates = [];
- // If the instruction specified in Result has defined an AsmMatchConverter
+ // If the instruction specified in Result has defined an AsmMatchConverter
// then setting this to 1 will cause the alias to use the AsmMatchConverter
// function when converting the OperandVector into an MCInst instead of the
// function that is generated by the dag Result.