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CFLTLS (immediate)

Compare unsigned lower than or same as immediate and fault

This instruction compares the unsigned value in a register with an immediate, and generates a Conditional fault exception if the register value is lower than or the same as the immediate. If an exception is generated, the <reason> operand is copied to ESR_ELx.

This instruction does not affect the condition flags.

This is a pseudo-instruction of CFLT<cc> (immediate). This means:

Fault class

(FEAT_CFLT)

313029282726252423222120191817161514131211109876543210
sf1110110011imm9h0000imm20imm9lRt
cc

32-bit lower encoding

(sf == 0)

CFLTLS #<reason>, <Wt>, #<imms1>

is equivalent to

CFLTLO #<reason>, <Wt>, #<imm>

64-bit lower encoding

(sf == 1)

CFLTLS #<reason>, <Xt>, #<imms1>

is equivalent to

CFLTLO #<reason>, <Xt>, #<imm>

Assembler Symbols

<reason>

Is a 2-bit unsigned immediate, in the range 0 to 3, encoded in the "imm2" field.

<Wt>

Is the 32-bit name of the general-purpose register to be tested, encoded in the "Rt" field.

<imms1>

Is a signed immediate, in the range -1 to 510, encoded as "imm9h:imm9l" minus 1.

<Xt>

Is the 64-bit name of the general-purpose register to be tested, encoded in the "Rt" field.

Operation

The description of CFLT<cc> (immediate) gives the operational pseudocode for this instruction.


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