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+Mono Intermediate Representation Documentation
+
+Operation: OP_ADDCC_IMM
+
+	Add immediate that will set the carry flag.  
+
+	dreg:
+		Destination register
+	inst_imm
+		Immediate value to add.
+	sreg1:
+		Source register to add.
+
+Operation: OP_CALL_HANDLER.
+
+	cil_code: 
+		Points to the CIL where the LEAVE or LEAVE_S
+		instruction was found.
+
+	inst_target_bb:
+		The target basic block for this invocation.
+
+	This instruction must call the target basic block.
+	
+Operation: OP_CISINST
+
+	Implements the CEE_MONO_CISINST opcode that is decoded from
+	the CIL stream.
+
+	This opcode takes as input an object reference and a class,
+	and leaves on the assigned register:
+
+		0. if the object is an instance of the class,
+		1. if the object is not instance of the class,
+		2. if the object is a proxy whose type cannot be determined.
+
+Operation: OP_CCASTCLASS
+
+	Implements the CEE_MONO_CCASTCLASS opcode that is decoded from
+	the CIL stream.
+
+	This opcode takes as input an object reference and a class,
+	and leaves on the assigned register:
+
+		0. if the object is an instance of the class,
+		1. if the object is a proxy whose type cannot be determined
+
+		throws an InvalidCastException exception otherwise.
+
+Operation: OP_LOCALLOC
+	inst_left:
+		The value 
+                                ins->inst_left = *sp;
+                                ins->cil_code = ip;
+
+	This is the equivalent of alloca() in a C implementation: it
+	allocates a bunch of bytes on the stack dynamically. Local
+	variables are allocated statically in the stack instead.
+	
+	It is implemented by moving the stack pointer according to the
+	platform ABI: you may need to keep a specific frame register
+	to address local variables when LOCALLOC is used (the PPC code
+	does this, for example: ifyou're doing the s390 port I suggest
+	starting from that)
+
+Operation: OP_SUBCC_IMM
+
+	Substract immediate that will set the borrow flag.
+
+	dreg:
+		Destination register
+	inst_imm
+		Immediate value to add.
+	sreg1:
+		Source register to add.