Branch instructions

beq       bge       bge_un       bgt       bgt_un       ble       ble_un       blt       blt_un       bne       br       br_long       br_peq       br_pne       brfalse       brnonnull       brnull       brtrue       switch

beq
·  Operation	Branch conditionally if int32 values are equal
·  Format	beq offset 0 0 0 0 br_long beq offset1 offset2 offset3 offset4
·  Direct Format	{beq} dest
·  Forms	beq = 162 (0xA2)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type int32. If the values are equal, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with br_peq. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

bge
·  Operation	Branch conditionally if int32 values are greater than or equal
·  Format	bge offset 0 0 0 0 br_long bge offset1 offset2 offset3 offset4
·  Direct Format	{bge} dest
·  Forms	bge = 170 (0xAA)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type int32. If value1 is greater than or equal to value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

bge_un
·  Operation	Branch conditionally if uint32 values are greater than or equal
·  Format	bge_un offset 0 0 0 0 br_long bge_un offset1 offset2 offset3 offset4
·  Direct Format	{bge_un} dest
·  Forms	bge_un = 171 (0xAB)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type uint32. If value1 is greater than or equal to value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

bgt
·  Operation	Branch conditionally if int32 values are greater than
·  Format	bgt offset 0 0 0 0 br_long bgt offset1 offset2 offset3 offset4
·  Direct Format	{bgt} dest
·  Forms	bgt = 168 (0xA8)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type int32. If value1 is greater than value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

bgt_un
·  Operation	Branch conditionally if uint32 values are greater than
·  Format	bgt_un offset 0 0 0 0 br_long bgt_un offset1 offset2 offset3 offset4
·  Direct Format	{bgt_un} dest
·  Forms	bgt_un = 169 (0xA9)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type uint32. If value1 is greater than value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

ble
·  Operation	Branch conditionally if int32 values are less than or equal
·  Format	ble offset 0 0 0 0 br_long ble offset1 offset2 offset3 offset4
·  Direct Format	{ble} dest
·  Forms	ble = 166 (0xA6)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type int32. If value1 is less than or equal to value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

ble_un
·  Operation	Branch conditionally if uint32 values are less than or equal
·  Format	ble_un offset 0 0 0 0 br_long ble_un offset1 offset2 offset3 offset4
·  Direct Format	{ble_un} dest
·  Forms	ble_un = 167 (0xA7)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type uint32. If value1 is less than or equal to value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

blt
·  Operation	Branch conditionally if int32 values are less than
·  Format	blt offset 0 0 0 0 br_long blt offset1 offset2 offset3 offset4
·  Direct Format	{blt} dest
·  Forms	blt = 164 (0xA4)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type int32. If value1 is less than value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

blt_un
·  Operation	Branch conditionally if uint32 values are less than
·  Format	blt_un offset 0 0 0 0 br_long blt_un offset1 offset2 offset3 offset4
·  Direct Format	{blt_un} dest
·  Forms	blt_un = 165 (0xA5)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type uint32. If value1 is less than value2, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.

bne
·  Operation	Branch conditionally if int32 values are not equal
·  Format	bne offset 0 0 0 0 br_long bne offset1 offset2 offset3 offset4
·  Direct Format	{bne} dest
·  Forms	bne = 163 (0xA3)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type int32. If the values are not equal, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with br_pne. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

br
·  Operation	Branch unconditionally
·  Format	br offset 0 0 0 0 br_long br offset1 offset2 offset3 offset4
·  Direct Format	{br} dest
·  Forms	br = 161 (0xA1)
·  Stack	... => ...
· Description	In the first form, the program branches to the address pc + offset, where pc is the address of the first byte of the br instruction, and offset is a signed 8-bit quantity. In the second form, offset is constructed by interpreting offset1, ..., offset4 as a 32-bit signed quantity in little-endian order.
· Notes	Branch instructions are always 6 bytes long, but may contain either short or long forms of a branch. The short form is always "opcode offset pad" where offset is an 8-bit offset and pad is 4 bytes of padding. The long form is always "br.long opcode loffset" where loffset is a 32-bit offset. This allows the code generator to output branch instructions with a uniform length, while the interpreter runs faster on short branches.

br_long
·  Operation	Modify a branch instruction to its long form
·  Format	br_long opcode ...
·  Forms	br_long = 178 (0xB2)
· Description	The br_long instruction modifies a branch instruction to take longer operands.
· Notes	The documentation for other branch instructions includes information on their long forms. There is no direct format for this instruction, because br_long is not required for the direct encoding.

br_peq
·  Operation	Branch conditionally if ptr values are equal
·  Format	br_peq offset 0 0 0 0 br_long br_peq offset1 offset2 offset3 offset4
·  Direct Format	{br_peq} dest
·  Forms	br_peq = 176 (0xB0)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type ptr. If the values are equal, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with beq. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

br_pne
·  Operation	Branch conditionally if ptr values are not equal
·  Format	br_pne offset 0 0 0 0 br_long br_pne offset1 offset2 offset3 offset4
·  Direct Format	{br_pne} dest
·  Forms	br_pne = 177 (0xB1)
·  Stack	..., value1, value2 => ...
· Description	Both value1 and value2 are popped from the stack as type ptr. If the values are not equal, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with bne. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

brfalse
·  Operation	Branch conditionally if int32 value is zero
·  Format	brfalse offset 0 0 0 0 br_long brfalse offset1 offset2 offset3 offset4
·  Direct Format	{brfalse} dest
·  Forms	brfalse = 173 (0xAD)
·  Stack	..., value => ...
· Description	The value is popped from the stack as type int32. If value is zero, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with brnull. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

brnonnull
·  Operation	Branch conditionally if ptr value is not null
·  Format	brnonnull offset 0 0 0 0 br_long brnonnull offset1 offset2 offset3 offset4
·  Direct Format	{brnonnull} dest
·  Forms	brnonnull = 175 (0xAF)
·  Stack	..., value => ...
· Description	The value is popped from the stack as type ptr. If value is not null, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with brtrue. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

brnull
·  Operation	Branch conditionally if ptr value is null
·  Format	brnull offset 0 0 0 0 br_long brnull offset1 offset2 offset3 offset4
·  Direct Format	{brnull} dest
·  Forms	brnull = 174 (0xAE)
·  Stack	..., value => ...
· Description	The value is popped from the stack as type ptr. If value is null, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with brfalse. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

brtrue
·  Operation	Branch conditionally if int32 value is non-zero
·  Format	brtrue offset 0 0 0 0 br_long brtrue offset1 offset2 offset3 offset4
·  Direct Format	{brtrue} dest
·  Forms	brtrue = 172 (0xAC)
·  Stack	..., value => ...
· Description	The value is popped from the stack as type int32. If value is non-zero, then the program branches to pc + offset. Otherwise, the program continues with the next instruction.
· Notes	This instruction must not be confused with brnonnull. Values of type int32 and ptr do not necessarily occupy the same amount of space in a stack word on all platforms.

switch
·  Operation	Switch on uint32 value
·  Format	switch max defoffset ...
·  Direct Format	{switch} max defaddr ...
·  Forms	switch = 179 (0xB3)
·  Stack	..., value => ...
· Description	The value is popped from the stack as type uint32. If it is greater than or equal to max, then the program continues at pc + defoffset. Otherwise, the 32-bit signed value at pc + 9 + value * 4 is fetched and added to pc.
· Notes	The max value is an unsigned 32-bit value, and the defoffset is a signed 32-bit value. All 32-bit values are in little-endian byte order.

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Licensed under GNU FDL