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BSTART

Ch 04   Block ISA — Block-structured Control Flow  |  **Group:** BSTART  |  **Forms:** 20  |  **Unique mnemonics:** 8

Block split instructions with CALL/RET/commit argument encoding.

Instructions

Mnemonic Assembly Length Decode Description
BSTART CALL BSTART.CALL <br_label>, <rt_label>, ->ra 32 Atomic fused call with independent call-target and return-target fields; transfers to the call block and writes ra. This exact aggregate is distinct from the generic bare-call form, which preserves ra and requires an adjacent SETRET or C.SETRET.
HL.BSTART CALL HL.BSTART.CALL <br_label>, <rt_label>, ->ra 48 [48-bit HL.] Atomic fused call with independent call-target and return-target fields; transfers to the call block and writes ra. This exact aggregate is distinct from the generic bare-call form, which preserves ra and requires an adjacent SETRET or C.SETRET.
HL.BSTART.FP HL.BSTART.FP FALL<, fixup_label> 48 [48-bit HL.] Terminates the current block and begins the next.
HL.BSTART.STD HL.BSTART.STD FALL<, fixup_label> 48 [48-bit HL.] Terminates the current block and begins the next.
HL.BSTART.SYS HL.BSTART.SYS FALL<, fixup_label> 48 [48-bit HL.] Terminates the current block and begins the next.
L.BSTART.FP L.BSTART.FP DIRECT, <label> 64 Instruction from the BSTART group.
L.BSTART.STD L.BSTART.STD COND, <label> 64 Instruction from the BSTART group.
L.BSTART.SYS L.BSTART.SYS FALL<, fixup_label> 64 Instruction from the BSTART group.

See Also