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mirror of https://github.com/TomHarte/CLK.git synced 2024-11-22 12:33:29 +00:00

Remove explanations; saying nothing is better than giving incomplete advice.

This commit is contained in:
Thomas Harte 2022-04-01 17:49:34 -04:00
parent 4671b8db5c
commit 8f580c256c

View File

@ -74,55 +74,31 @@ enum class Operation: uint8_t {
/// Absolute.
/// abs abs. abso abso.
/// rD(), rA() [oe(), rc()]
///
/// |rA| is placed into rD. If rA = 0x8000'0000 then 0x8000'0000 is placed into rD
/// and XER[OV] is set if oe() indicates that overflow is enabled.
absx,
/// Cache line compute size.
/// clcs
/// rD(), rA()
///
/// The size of the cache line specified by rA is placed into rD. Cf. the CacheLine enum.
/// As an aside: all cache lines are 64 bytes on the MPC601.
clcs,
/// Divide.
/// div div. divo divo.
/// rD(), rA(), rB() [rc(), oe()]
///
/// Unsigned 64-bit divide. rA|MQ / rB is placed into rD and the
/// remainder is placed into MQ. The ermainder has the same sign as the dividend
/// such that remainder + divisor * quotient = dividend.
///
/// rc() != 0 => the LT, GT and EQ bits in CR are set as per the remainder.
/// oe() != 0 => SO and OV are set if the quotient exceeds 32 bits.
divx,
/// Divide short.
/// divs divs. divso divso.
/// rD(), rA(), rB() [rc(), eo()]
///
/// Signed 32-bit divide. rD = rA/rB; remainder is
/// placed into MQ. The ermainder has the same sign as the dividend
/// such that remainder + divisor * quotient = dividend.
///
/// rc() != 0 => the LT, GT and EQ bits in CR are set as per the remainder.
/// oe() != 0 => SO and OV are set if the quotient exceeds 32 bits.
divsx,
/// Difference or zero.
/// doz doz. dozo dozo.
/// rD(), rA(), rB() [rc(), oe()]
///
/// if rA > rB then rD = 0; else rD = NOT(rA) + rB + 1.
dozx,
/// Difference or zero immediate.
/// dozi
/// rD(), rA(), simm()
///
/// if rA > simm() then rD = 0; else rD = NOT(rA) + simm() + 1.
dozi,
lscbxx, maskgx, maskirx,
@ -142,69 +118,46 @@ enum class Operation: uint8_t {
/// Add.
/// add add. addo addo.
/// rD(), rA(), rB() [rc(), oe()]
///
/// rD() = rA() + rB(). Carry is ignored, rD() may be equal to rA() or rB().
addx,
/// Add carrying.
/// addc addc. addco addco.
/// rD(), rA(), rB() [rc(), oe()]
///
/// rD() = rA() + rB().
/// XER[CA] is updated with carry; if oe() is set then so are XER[SO] and XER[OV].
/// if rc() is set, LT, GT, EQ and SO condition bits are updated.
addcx,
/// Add extended.
/// adde adde. addeo addeo.
/// rD(), rA(), rB() [rc(), eo()]
///
/// rD() = rA() + rB() + XER[CA]; XER[CA] is set if further carry occurs.
/// oe() and rc() apply.
addex,
/// Add immediate.
/// addi
/// rD(), rA(), simm()
///
/// rD() = (rA() | 0) + simm()
addi,
/// Add immediate carrying.
/// addic
/// rD(), rA(), simm()
///
/// rD() = (rA() | 0) + simm()
/// XER[CA] is updated.
addic,
/// Add immediate carrying and record.
/// addic.
/// rD(), rA(), simm()
///
/// rD() = (rA() | 0) + simm()
/// XER[CA] and the condition register are updated.
addic_,
/// Add immediate shifted.
/// addis.
/// rD(), rA(), simm()
///
/// rD() = (rA() | 0) + (simm() << 16)
addis,
/// Add to minus one.
/// addme addme. addmeo addmeo.
/// rD(), rA() [rc(), oe()]
///
/// rD() = rA() + XER[CA] + 0xffff'ffff
addmex,
/// Add to zero extended.
/// addze addze. addzeo addzeo.
/// rD(), rA() [rc(), oe()]
///
/// rD() = rA() + XER[CA]
addzex,
/// And.
@ -230,39 +183,21 @@ enum class Operation: uint8_t {
/// Branch unconditional.
/// b bl ba bla
/// li() [aa(), lk()]
///
/// Use li() to get the included immediate value.
///
/// Use aa() to determine whether it's a relative (aa() = 0) or absolute (aa() != 0) address.
/// Also check lk() to determine whether to update the link register.
bx,
/// Branch conditional.
/// bne bne+ beq bdnzt+ bdnzf bdnzt bdnzfla ...
/// bo(), bi(), bd() [aa(), lk()]
///
/// aa() determines whether the branch has a relative or absolute target.
/// lk() determines whether to update the link register.
/// bd() supplies a relative displacment or absolute address.
/// bi() specifies which CR bit to use as a condition; cf. the Condition enum.
/// bo() provides other branch options and a branch prediction hint as per (BranchOptions enum << 1) | hint.
bcx,
/// Branch conditional to count register.
/// bctr bctrl bnectrl bnectrl bltctr blectr ...
/// bo(), bi() [aa(), lk()]
///
/// aa(), bi(), bo() and lk() are as per bcx.
///
/// On the MPC601, anything that decrements the count register will use the non-decremented
/// version as the branch target. Other processors will use the decremented version.
bcctrx,
/// Branch conditional to link register.
/// blr blrl bltlr blelrl bnelrl ...
/// bo(), bi() [aa(), lk()]
///
/// aa(), bi(), bo() and lk() are as per bcx.
bclrx,
/// Compare
@ -401,60 +336,27 @@ enum class Operation: uint8_t {
/// Load byte and zero with update indexed.
/// lbzux
///
/// rD()[24, 31] = [ rA()|0 + rB() ]; and rA() is set to the calculated address
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
/// The rest of rD is set to 0.
///
/// PowerPC defines rA=0 and rA=rD to be invalid forms; the MPC601
/// will suppress the update if rA=0 or rA=rD.
lbzux,
/// Load byte and zero indexed.
/// lbzx
///
/// rD[24, 31] = [ (rA()|0) + rB() ]
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
/// The rest of rD is set to 0.
lbzx,
lfd, lfdu, lfdux, lfdx, lfs, lfsu,
lfsux, lfsx, lha, lhau,
/// Load half-word algebraic with update indexed.
///
/// rD()[16, 31] = [ rA()|0 + rB() ]; and rA() is set to the calculated address
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
/// The result in rD is sign extended.
///
/// PowerPC defines rA=0 and rA=rD to be invalid forms; the MPC601
/// will suppress the update if rA=0 or rA=rD.
lhaux,
/// Load half-word algebraic indexed.
///
/// rD[16, 31] = [ (rA()|0) + rB() ]
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
/// The result in rD is sign extended.
lhax,
lhbrx, lhz, lhzu,
/// Load half-word and zero with update indexed.
///
/// rD()[16, 31] = [ rA()|0 + rB() ]; and rA() is set to the calculated address
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
/// The rest of rD is set to 0.
///
/// PowerPC defines rA=0 and rA=rD to be invalid forms; the MPC601
/// will suppress the update if rA=0 or rA=rD.
lhzux,
/// Load half-word and zero indexed.
///
/// rD[16, 31] = [ (rA()|0) + rB() ]
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
/// The rest of rD is set to 0.
lhzx,
lmw,
@ -462,19 +364,10 @@ enum class Operation: uint8_t {
/// Load word and zero with update indexed.
/// lwzux
///
/// rD() = [ rA()|0 + rB() ]; and rA() is set to the calculated address
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
///
/// PowerPC defines rA=0 and rA=rD to be invalid forms; the MPC601
/// will suppress the update if rA=0 or rA=rD.
lwzux,
/// Load word and zero indexed.
/// lwzx
///
/// rD() = [ (rA()|0) + rB() ]
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
lwzx,
mcrf, mcrfs, mcrxr,
@ -499,9 +392,6 @@ enum class Operation: uint8_t {
mulhwux,
/// Multiply low immediate.
///
/// rD() = [low 32 bits of] rA() * simm()
/// XER[OV] is set if, were the operands treated as signed, overflow occurred.
mulli,
/// Multiply low word.
@ -548,66 +438,36 @@ enum class Operation: uint8_t {
stb, stbu,
/// Store byte with update indexed.
///
/// [ (ra()|0) + rB() ] = rS()[24, 31]; and rA() is updated with the calculated address.
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
///
/// PowerPC defines rA=0 to an invalid form; the MPC601 will store to r0.
stbux,
/// Store byte indexed.
///
/// [ (ra()|0) + rB() ] = rS()[24, 31]
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
stbx,
stfd, stfdu,
stfdux, stfdx, stfs, stfsu, stfsux, stfsx, sth, sthbrx, sthu,
/// Store half-word with update indexed.
///
/// [ (ra()|0) + rB() ] = rS()[16, 31]; and rA() is updated with the calculated address.
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
///
/// PowerPC defines rA=0 to an invalid form; the MPC601 will store to r0.
sthux,
/// Store half-word indexed.
///
/// [ (ra()|0) + rB() ] = rS()[16, 31]
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
sthx,
stmw, stswi, stswx, stw, stwbrx, stwcx_, stwu,
/// Store word with update indexed.
///
/// [ (ra()|0) + rB() ] = rS(); and rA() is updated with the calculated address.
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
///
/// PowerPC defines rA=0 to an invalid form; the MPC601 will store to r0.
stwux,
/// Store word indexed.
///
/// [ (ra()|0) + rB() ] = rS()
/// i.e. if rA() is 0 then the value 0 is used, not the contents of r0.
stwx,
subfx,
/// Subtract from carrying.
/// subfc subfc. subfco subfco.
///
/// rD() = -rA() +rB() + 1
///
/// oe(), rc() apply.
subfcx,
subfex,
/// Subtract from immediate carrying
///
/// rD() = ~rA() + simm() + 1
subfic,
subfmex, subfzex, sync, tw, twi, xorx, xori, xoris, mftb,