BC.cond

Branch consistent conditionally

This instruction branches conditionally to a label at a PC-relative offset, with a hint that this branch is very unlikely to change direction. This instruction provides a hint that this is not a subroutine call or return.

19-bit signed PC-relative branch offset class

(FEAT_HBC)

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
0	1	0	1	0	1	0	0	imm19																			1	cond
																											o0

Encoding

BC.<cond> <label>

Decode

if !IsFeatureImplemented(FEAT_HBC) then EndOfDecode(Decode_UNDEF); constant bits(64) offset = SignExtend(imm19:'00', 64); constant bits(4) condition = cond;

Assembler Symbols

<cond>

Is one of the standard conditions, encoded in the standard way, and encoded in cond:

cond	<cond>
0000	EQ
0001	NE
0010	CS
0011	CC
0100	MI
0101	PL
0110	VS
0111	VC
1000	HI
1001	LS
1010	GE
1011	LT
1100	GT
1101	LE
1110	AL
1111	NV

<label>

Is the program label to be conditionally branched to. Its offset from the address of this instruction, in the range +/-1MB, is encoded as "imm19" times 4.

Operation

constant boolean branch_conditional = TRUE; if ConditionHolds(condition) then BranchTo(PC64 + offset, BranchType_DIR, branch_conditional); else BranchNotTaken(BranchType_DIR, branch_conditional);