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Made the annul of unconditional conditional branches behave properly, added code to read and write the strand_sts_reg, and made restored a Priv instruction.

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--HG--
extra : convert_revision : 386512215f7243d230717c369217f8d2f9ada935
This commit is contained in:
Gabe Black 2006-11-10 15:27:06 -05:00
parent 27b43b62b7
commit 7bf1c8981d
1 changed files with 57 additions and 13 deletions
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70
src/arch/sparc/isa/decoder.isa
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@ -41,15 +41,16 @@ decode OP default Unknown::unknown()
0x0: Trap::illtrap({{fault = new IllegalInstruction;}});
format BranchN
{
//bpcc
0x1: decode COND2
{
//Branch Always
0x8: decode A
{
0x0: b(19, {{
0x0: bpa(19, {{
NNPC = xc->readPC() + disp;
}});
0x1: b(19, {{
0x1: bpa(19, {{
NPC = xc->readPC() + disp;
NNPC = NPC + 4;
}}, ',a');
@ -57,10 +58,10 @@ decode OP default Unknown::unknown()
//Branch Never
0x0: decode A
{
0x0: bn(19, {{
0x0: bpn(19, {{
NNPC = NNPC;//Don't do anything
}});
0x1: bn(19, {{
0x1: bpn(19, {{
NPC = xc->readNextPC() + 4;
NNPC = NPC + 4;
}}, ',a');
@ -81,12 +82,38 @@ decode OP default Unknown::unknown()
}});
}
}
0x2: bicc(22, {{
if(passesCondition(Ccr<3:0>, COND2))
NNPC = xc->readPC() + disp;
else
handle_annul
}});
//bicc
0x2: decode COND2
{
//Branch Always
0x8: decode A
{
0x0: ba(22, {{
NNPC = xc->readPC() + disp;
}});
0x1: ba(22, {{
NPC = xc->readPC() + disp;
NNPC = NPC + 4;
}}, ',a');
}
//Branch Never
0x0: decode A
{
0x0: bn(22, {{
NNPC = NNPC;//Don't do anything
}});
0x1: bn(22, {{
NPC = xc->readNextPC() + 4;
NNPC = NPC + 4;
}}, ',a');
}
default: bicc(22, {{
if(passesCondition(Ccr<3:0>, COND2))
NNPC = xc->readPC() + disp;
else
handle_annul
}});
}
}
0x3: decode RCOND2
{
@ -380,7 +407,15 @@ decode OP default Unknown::unknown()
0x17: Priv::rdtick_cmpr({{Rd = TickCmpr;}});
0x18: PrivCheck::rdstick({{Rd = Stick}}, {{Stick<63:>}});
0x19: Priv::rdstick_cmpr({{Rd = StickCmpr;}});
//0x1A-0x1F should cause an illegal instruction exception
0x1A: Priv::rdstrand_sts_reg({{
if(Pstate<2:> && !Hpstate<2:>)
Rd = StrandStsReg<0:>;
else
Rd = StrandStsReg;
}});
//0x1A is supposed to be reserved, but it reads the strand
//status register.
//0x1B-0x1F should cause an illegal instruction exception
}
0x29: decode RS1 {
0x00: HPriv::rdhprhpstate({{Rd = Hpstate;}});
@ -515,7 +550,16 @@ decode OP default Unknown::unknown()
Stick = Rs1 ^ Rs2_or_imm13;
}});
0x19: Priv::wrstick_cmpr({{StickCmpr = Rs1 ^ Rs2_or_imm13;}});
//0x1A-0x1F should cause an illegal instruction exception
0x1A: Priv::wrstrand_sts_reg({{
if(Pstate<2:> && !Hpstate<2:>)
StrandStsReg = StrandStsReg<63:1> |
(Rs1 ^ Rs2_or_imm13)<0:>;
else
StrandStsReg = Rs1 ^ Rs2_or_imm13;
}});
//0x1A is supposed to be reserved, but it writes the strand
//status register.
//0x1B-0x1F should cause an illegal instruction exception
}
0x31: decode FCN {
0x0: Priv::saved({{
@ -527,7 +571,7 @@ decode OP default Unknown::unknown()
else
Otherwin = Otherwin - 1;
}});
0x1: BasicOperate::restored({{
0x1: Priv::restored({{
assert(Cansave || Otherwin);
assert(Canrestore < NWindows - 2);
Canrestore = Canrestore + 1;