From ae8af2944f5c7b0c622f8dfde2c1098589d92093 Mon Sep 17 00:00:00 2001 From: lkcl Date: Fri, 6 Aug 2021 11:44:05 +0100 Subject: [PATCH] --- openpower/sv/branches.mdwn | 38 ++++---------------------------------- 1 file changed, 4 insertions(+), 34 deletions(-) diff --git a/openpower/sv/branches.mdwn b/openpower/sv/branches.mdwn index c561baa47..3f313e2b9 100644 --- a/openpower/sv/branches.mdwn +++ b/openpower/sv/branches.mdwn @@ -161,42 +161,12 @@ Available options to combine: In addition to the above, it is necessary to select whether, in `svstep` mode, the Vector CR Field is to be overwritten or not: in some cases it is useful to know but in others all that is needed is the branch itself. -In the case of `sv.bc` there is no additional bitspace, so on the -basis that it is rarely used, the `AA` -field is re-interpreted instead to be `Rc`. For `sv.bclr`, there is free -bitspace and so bit 16 has been chosen as `Rc`. **These interpretations are only available for sv.bc, they are NOT available for Power ISA v3.0B** i.e. only when embedded in an SVP64 Prefix Context do these and all other parts of this specification apply. -Form: B-Form (see [[isatables/fields.text]]) - -| 0.5|6.10|11.15|16..29| 30 |31| name | -| -- | -- | --- | ---- | -- |--| ------- | -|16 | BO | BI | BD | Rc |LK| sv.bc | - -Form: XL-Form (see [[isatables/fields.text]]) - -| 0.5|6.10|11.15|16|17.18|19.20|21..30|31| name | -| -- | -- | --- |--|---- |-----|------|--| ------- | -|19 | BO | BI |Rc| // | BH | 19 |LK| sv.bclr | - -Pseudocode for Rc in sv.bc - -``` -# Use bit 30 as Rc, disable AA -Rc = AA -AA = 0 -``` - -Pseudocode for Rc in sv.bclr - -``` -# use bit 16 of opcode as Rc -Rc = instr[16] -``` Pseudocode for Horizontal-First Mode: @@ -209,10 +179,10 @@ for srcstep in range(VL): SVCRf = SVP64EXTRA(BI>>2) if svstep_mode then new_srcstep, CRbits = SVSTATE_NEXT(srcstep) + if BRc = 1 then # CR Vectorised overwritr + CR{SVCRf+srcstep} = CRbits else CRbits = CR{SVCRf} - if Rc = 1 then # CR0 Vectorised - CR{0+srcstep} = CRbits testbit = CRbits[BI & 0b11] # testbit = CR[BI+32+srcstep*4] else if not SVRMmode.sz: @@ -255,8 +225,8 @@ else CRbits = CR{SVCRf} # select predicate bit or zero/one if predicate[srcstep]: - if Rc = 1 then # CR0 vectorised - CR{0+srcstep} = CRbits + if BRc = 1 then # CR0 vectorised + CR{SVCRf+srcstep} = CRbits testbit = CRbits[BI & 0b11] else if not SVRMmode.sz: SVSTATE.srcstep = new_srcstep -- 2.30.2