192 lines
		
	
	
		
			8.4 KiB
		
	
	
	
		
			TableGen
		
	
	
	
			
		
		
	
	
			192 lines
		
	
	
		
			8.4 KiB
		
	
	
	
		
			TableGen
		
	
	
	
| //===- WebAssemblyInstrControl.td-WebAssembly control-flow ------*- tablegen -*-
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| //
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| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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| // See https://llvm.org/LICENSE.txt for license information.
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| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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| //
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| //===----------------------------------------------------------------------===//
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| ///
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| /// \file
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| /// WebAssembly control-flow code-gen constructs.
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| ///
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| //===----------------------------------------------------------------------===//
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| 
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| let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in {
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| // The condition operand is a boolean value which WebAssembly represents as i32.
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| defm BR_IF : I<(outs), (ins bb_op:$dst, I32:$cond),
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|                (outs), (ins bb_op:$dst),
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|                [(brcond I32:$cond, bb:$dst)],
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|                 "br_if   \t$dst, $cond", "br_if   \t$dst", 0x0d>;
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| let isCodeGenOnly = 1 in
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| defm BR_UNLESS : I<(outs), (ins bb_op:$dst, I32:$cond),
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|                    (outs), (ins bb_op:$dst), []>;
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| let isBarrier = 1 in
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| defm BR   : NRI<(outs), (ins bb_op:$dst),
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|                 [(br bb:$dst)],
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|                 "br      \t$dst", 0x0c>;
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| } // isBranch = 1, isTerminator = 1, hasCtrlDep = 1
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| 
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| def : Pat<(brcond (i32 (setne I32:$cond, 0)), bb:$dst),
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|           (BR_IF bb_op:$dst, I32:$cond)>;
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| def : Pat<(brcond (i32 (seteq I32:$cond, 0)), bb:$dst),
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|           (BR_UNLESS bb_op:$dst, I32:$cond)>;
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| 
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| // A list of branch targets enclosed in {} and separated by comma.
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| // Used by br_table only.
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| def BrListAsmOperand : AsmOperandClass { let Name = "BrList"; }
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| let OperandNamespace = "WebAssembly", OperandType = "OPERAND_BRLIST" in
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| def brlist : Operand<i32> {
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|   let ParserMatchClass = BrListAsmOperand;
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|   let PrintMethod = "printBrList";
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| }
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| 
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| // TODO: SelectionDAG's lowering insists on using a pointer as the index for
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| // jump tables, so in practice we don't ever use BR_TABLE_I64 in wasm32 mode
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| // currently.
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| let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
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| defm BR_TABLE_I32 : I<(outs), (ins I32:$index, variable_ops),
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|                       (outs), (ins brlist:$brl),
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|                       [(WebAssemblybr_table I32:$index)],
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|                       "br_table \t$index", "br_table \t$brl",
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|                       0x0e>;
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| defm BR_TABLE_I64 : I<(outs), (ins I64:$index, variable_ops),
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|                       (outs), (ins brlist:$brl),
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|                       [(WebAssemblybr_table I64:$index)],
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|                       "br_table \t$index", "br_table \t$brl",
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|                       0x0e>;
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| } // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
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| 
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| // This is technically a control-flow instruction, since all it affects is the
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| // IP.
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| defm NOP : NRI<(outs), (ins), [], "nop", 0x01>;
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| 
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| // Placemarkers to indicate the start or end of a block or loop scope.
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| // These use/clobber VALUE_STACK to prevent them from being moved into the
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| // middle of an expression tree.
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| let Uses = [VALUE_STACK], Defs = [VALUE_STACK] in {
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| defm BLOCK : NRI<(outs), (ins Signature:$sig), [], "block   \t$sig", 0x02>;
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| defm LOOP  : NRI<(outs), (ins Signature:$sig), [], "loop    \t$sig", 0x03>;
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| 
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| defm IF : I<(outs), (ins Signature:$sig, I32:$cond),
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|             (outs), (ins Signature:$sig),
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|             [], "if    \t$sig, $cond", "if    \t$sig", 0x04>;
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| defm ELSE : NRI<(outs), (ins), [], "else", 0x05>;
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| 
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| // END_BLOCK, END_LOOP, END_IF and END_FUNCTION are represented with the same
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| // opcode in wasm.
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| defm END_BLOCK : NRI<(outs), (ins), [], "end_block", 0x0b>;
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| defm END_LOOP  : NRI<(outs), (ins), [], "end_loop", 0x0b>;
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| defm END_IF    : NRI<(outs), (ins), [], "end_if", 0x0b>;
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| // Generic instruction, for disassembler.
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| let IsCanonical = 1 in
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| defm END       : NRI<(outs), (ins), [], "end", 0x0b>;
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| let isTerminator = 1, isBarrier = 1 in
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| defm END_FUNCTION : NRI<(outs), (ins), [], "end_function", 0x0b>;
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| } // Uses = [VALUE_STACK], Defs = [VALUE_STACK]
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| 
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| multiclass RETURN<WebAssemblyRegClass vt> {
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|   defm RETURN_#vt : I<(outs), (ins vt:$val), (outs), (ins),
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|                       [(WebAssemblyreturn vt:$val)],
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|                       "return  \t$val", "return", 0x0f>;
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|   // Equivalent to RETURN_#vt, for use at the end of a function when wasm
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|   // semantics return by falling off the end of the block.
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|   let isCodeGenOnly = 1 in
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|   defm FALLTHROUGH_RETURN_#vt : I<(outs), (ins vt:$val), (outs), (ins), []>;
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| }
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| 
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| multiclass SIMD_RETURN<ValueType vt> {
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|   defm RETURN_#vt : I<(outs), (ins V128:$val), (outs), (ins),
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|                       [(WebAssemblyreturn (vt V128:$val))],
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|                       "return  \t$val", "return", 0x0f>,
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|                     Requires<[HasSIMD128]>;
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|   // Equivalent to RETURN_#vt, for use at the end of a function when wasm
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|   // semantics return by falling off the end of the block.
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|   let isCodeGenOnly = 1 in
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|   defm FALLTHROUGH_RETURN_#vt : I<(outs), (ins V128:$val), (outs), (ins),
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|                                   []>,
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|                                   Requires<[HasSIMD128]>;
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| }
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| 
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| let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
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| 
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| let isReturn = 1 in {
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|   defm "": RETURN<I32>;
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|   defm "": RETURN<I64>;
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|   defm "": RETURN<F32>;
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|   defm "": RETURN<F64>;
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|   defm "": RETURN<EXNREF>;
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|   defm "": SIMD_RETURN<v16i8>;
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|   defm "": SIMD_RETURN<v8i16>;
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|   defm "": SIMD_RETURN<v4i32>;
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|   defm "": SIMD_RETURN<v2i64>;
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|   defm "": SIMD_RETURN<v4f32>;
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|   defm "": SIMD_RETURN<v2f64>;
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| 
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|   defm RETURN_VOID : NRI<(outs), (ins), [(WebAssemblyreturn)], "return", 0x0f>;
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| 
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|   // This is to RETURN_VOID what FALLTHROUGH_RETURN_#vt is to RETURN_#vt.
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|   let isCodeGenOnly = 1 in
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|   defm FALLTHROUGH_RETURN_VOID : NRI<(outs), (ins), []>;
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| } // isReturn = 1
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| 
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| defm UNREACHABLE : NRI<(outs), (ins), [(trap)], "unreachable", 0x00>;
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| } // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
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| 
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| //===----------------------------------------------------------------------===//
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| // Exception handling instructions
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| //===----------------------------------------------------------------------===//
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| 
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| let Predicates = [HasExceptionHandling] in {
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| 
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| // Throwing an exception: throw / rethrow
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| let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
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| defm THROW : I<(outs), (ins event_op:$tag, variable_ops),
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|                (outs), (ins event_op:$tag),
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|                [(WebAssemblythrow (WebAssemblywrapper texternalsym:$tag))],
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|                "throw   \t$tag", "throw   \t$tag", 0x08>;
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| defm RETHROW : I<(outs), (ins EXNREF:$exn), (outs), (ins), [],
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|                  "rethrow \t$exn", "rethrow", 0x09>;
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| // Pseudo instruction to be the lowering target of int_wasm_rethrow_in_catch
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| // intrinsic. Will be converted to the real rethrow instruction later.
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| let isPseudo = 1 in
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| defm RETHROW_IN_CATCH : NRI<(outs), (ins), [(int_wasm_rethrow_in_catch)],
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|                             "rethrow_in_catch", 0>;
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| } // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
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| 
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| // Region within which an exception is caught: try / end_try
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| let Uses = [VALUE_STACK], Defs = [VALUE_STACK] in {
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| defm TRY     : NRI<(outs), (ins Signature:$sig), [], "try     \t$sig", 0x06>;
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| defm END_TRY : NRI<(outs), (ins), [], "end_try", 0x0b>;
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| } // Uses = [VALUE_STACK], Defs = [VALUE_STACK]
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| 
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| // Catching an exception: catch / extract_exception
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| let hasCtrlDep = 1, hasSideEffects = 1 in
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| defm CATCH : I<(outs EXNREF:$dst), (ins), (outs), (ins), [],
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|                "catch   \t$dst", "catch", 0x07>;
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| 
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| // Querying / extracing exception: br_on_exn
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| // br_on_exn queries an exnref to see if it matches the corresponding exception
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| // tag index. If true it branches to the given label and pushes the
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| // corresponding argument values of the exception onto the stack.
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| let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in
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| defm BR_ON_EXN : I<(outs), (ins bb_op:$dst, event_op:$tag, EXNREF:$exn),
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|                    (outs), (ins bb_op:$dst, event_op:$tag), [],
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|                    "br_on_exn \t$dst, $tag, $exn", "br_on_exn \t$dst, $tag",
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|                    0x0a>;
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| // This is a pseudo instruction that simulates popping a value from stack, which
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| // has been pushed by br_on_exn
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| let isCodeGenOnly = 1, hasSideEffects = 1 in
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| defm EXTRACT_EXCEPTION_I32 : NRI<(outs I32:$dst), (ins),
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|                                  [(set I32:$dst, (int_wasm_extract_exception))],
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|                                  "extract_exception\t$dst">;
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| 
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| // Pseudo instructions: cleanupret / catchret
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| let isTerminator = 1, hasSideEffects = 1, isBarrier = 1, hasCtrlDep = 1,
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|     isPseudo = 1, isEHScopeReturn = 1 in {
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|   defm CLEANUPRET : NRI<(outs), (ins), [(cleanupret)], "cleanupret", 0>;
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|   defm CATCHRET : NRI<(outs), (ins bb_op:$dst, bb_op:$from),
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|                       [(catchret bb:$dst, bb:$from)], "catchret", 0>;
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| } // isTerminator = 1, hasSideEffects = 1, isBarrier = 1, hasCtrlDep = 1,
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|   // isPseudo = 1, isEHScopeReturn = 1
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| } // Predicates = [HasExceptionHandling]
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