Compaq ECQD2KCTE manual Rdps, Readunq, Rei, Remqhilr, Remqhiq

Table 9–1 : Unprivileged OpenVMS Alpha PALcode Instruction Summary (Continued)

Mnemonic	Operation and Description
RD_PS	Read processor status
	RD_PS writes the Processor Status (PS) to register R0.
READ_UNQ	Read unique context
	READ_UNQ reads the hardware process (thread) unique context value, if
	previously written by WRITE_UNQ, and places that value in R0.
REI	Return from exception or interrupt
	The PS, PC, and saved R2..R7 are popped from the current stack and held in
	temporary registers. The new PS is checked for validity and consistency. If it
	is valid and consistent, the current stack pointer is then saved and a new stack
	pointer is selected. Registers R2 through R7 are restored by using the saved
	values held in the temporary registers. A check is made to determine if an
	AST or interrupt is pending.If the enabling conditions are present for an inter-
	rupt or AST at the completion of this instruction, the interrupt or AST occurs
	before the next instruction.
REMQHIL	Remove from longword queue at header, interlocked
	The self-relative queue entry following the header, pointed to by R16, is
	removed from the queue, and the address of the removed entry is returned in
	R1. The removal is interlocked to prevent concurrent interlocked insertions or
	removals at the head or tail of the same queue by another process, in a multi-
	processor environment. The removal is a noninterruptible operation.
REMQHILR	Remove from longword queue at header, interlocked resident
	The queue entry following the header, pointed to by R16, is removed from the
	self-relative queue, and the address of the removed entry is returned in R1.
	The removal is interlocked to prevent concurrent interlocked insertions or
	removals at the head or tail of the same queue by another process, in a multi-
	processor environment. The removal is a noninterruptible operation. This
	instruction requires that the queue be memory-resident and that the queue
	header and elements are quadword-aligned.
REMQHIQ	Remove from quadword queue at header, interlocked
	The self-relative queue entry following the header, pointed to by R16, is
	removed from the queue and the address of the removed entry is returned in
	R1. The removal is interlocked to prevent concurrent interlocked insertions or
	removals at the head or tail of the same queue by another process, in a multi-
	processor environment. The removal is a noninterruptible operation.

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