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Replace explicit xc->misspeculating() tests in execute() methods

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with an IsNonSpeculative flag.
No effect on results of non-full-system or SimpleCPU.
Very small impact on full-system FullCPU runs since old wrong-path
call_pal insts used to change the PC, where now they're treated
as no-ops.

arch/alpha/isa_desc:
    Get rid of xc->misspeculating() checks, use IsNonSpeculative flag instead.
cpu/static_inst.hh:
    Add IsNonSpeculative flag and isNonSpeculative() method to test it.

--HG--
extra : convert_revision : 7ec536bfc28b905c429c09eb920ed73ef2beeeba
This commit is contained in:
Steve Reinhardt
2004-05-18 16:09:02 -07:00
parent 02af86f7e8
commit 4c55d26e66
2 changed files with 61 additions and 95 deletions
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151
arch/alpha/isa_desc
View File

@@ -1374,8 +1374,8 @@ output decoder {{
}
}};
def format EmulatedCallPal(code) {{
iop = InstObjParams(name, Name, 'EmulatedCallPal', CodeBlock(code))
def format EmulatedCallPal(code, *flags) {{
iop = InstObjParams(name, Name, 'EmulatedCallPal', CodeBlock(code), flags)
header_output = BasicDeclare.subst(iop)
decoder_output = BasicConstructor.subst(iop)
decode_block = BasicDecode.subst(iop)
@@ -1436,8 +1436,8 @@ output decoder {{
}
}};
def format CallPal(code) {{
iop = InstObjParams(name, Name, 'CallPalBase', CodeBlock(code))
def format CallPal(code, *flags) {{
iop = InstObjParams(name, Name, 'CallPalBase', CodeBlock(code), flags)
header_output = BasicDeclare.subst(iop)
decoder_output = BasicConstructor.subst(iop)
decode_block = BasicDecode.subst(iop)
@@ -1588,6 +1588,9 @@ output header {{
FailUnimplemented(const char *_mnemonic, MachInst _machInst)
: AlphaStaticInst(_mnemonic, _machInst, No_OpClass)
{
// don't call execute() (which panics) if we're on a
// speculative path
flags[IsNonSpeculative] = true;
}
%(BasicExecDeclare)s
@@ -1615,6 +1618,9 @@ output header {{
WarnUnimplemented(const char *_mnemonic, MachInst _machInst)
: AlphaStaticInst(_mnemonic, _machInst, No_OpClass), warned(false)
{
// don't call execute() (which panics) if we're on a
// speculative path
flags[IsNonSpeculative] = true;
}
%(BasicExecDeclare)s
@@ -1646,9 +1652,8 @@ output exec {{
FailUnimplemented::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData)
{
if (!xc->misspeculating())
panic("attempt to execute unimplemented instruction '%s' "
"(inst 0x%08x, opcode 0x%x)", mnemonic, machInst, OPCODE);
panic("attempt to execute unimplemented instruction '%s' "
"(inst 0x%08x, opcode 0x%x)", mnemonic, machInst, OPCODE);
return Unimplemented_Opcode_Fault;
}
@@ -1656,42 +1661,24 @@ output exec {{
WarnUnimplemented::execute(%(CPU_exec_context)s *xc,
Trace::InstRecord *traceData)
{
if (!xc->misspeculating())
if (!warned) {
warn("instruction '%s' unimplemented\n", mnemonic);
warned = true;
}
if (!warned) {
warn("instruction '%s' unimplemented\n", mnemonic);
warned = true;
}
return No_Fault;
}
}};
def template WarnUnimplDeclare {{
/**
* Static instruction class for "%(mnemonic)s".
*/
class %(class_name)s : public %(base_class)s
{
public:
/// Constructor
%(class_name)s(MachInst machInst)
: %(base_class)s("%(mnemonic)s", machInst)
{
}
};
}};
def format FailUnimpl() {{
iop = InstObjParams(name, 'FailUnimplemented')
decode_block = BasicDecodeWithMnemonic.subst(iop)
}};
def format WarnUnimpl() {{
iop = InstObjParams(name, Name, 'WarnUnimplemented')
header_output = WarnUnimplDeclare.subst(iop)
decode_block = BasicDecode.subst(iop)
iop = InstObjParams(name, 'WarnUnimplemented')
decode_block = BasicDecodeWithMnemonic.subst(iop)
}};
output header {{
@@ -1707,6 +1694,9 @@ output header {{
Unknown(MachInst _machInst)
: AlphaStaticInst("unknown", _machInst, No_OpClass)
{
// don't call execute() (which panics) if we're on a
// speculative path
flags[IsNonSpeculative] = true;
}
%(BasicExecDeclare)s
@@ -1733,9 +1723,8 @@ output exec {{
Fault
Unknown::execute(%(CPU_exec_context)s *xc, Trace::InstRecord *traceData)
{
if (!xc->misspeculating())
panic("attempt to execute unknown instruction "
"(inst 0x%08x, opcode 0x%x)", machInst, OPCODE);
panic("attempt to execute unknown instruction "
"(inst 0x%08x, opcode 0x%x)", machInst, OPCODE);
return Unimplemented_Opcode_Fault;
}
}};
@@ -2420,16 +2409,12 @@ decode OPCODE default Unknown::unknown() {
format BasicOperate {
0xe000: rc({{
Ra = xc->readIntrFlag();
if (!xc->misspeculating()) {
xc->setIntrFlag(0);
}
}});
xc->setIntrFlag(0);
}}, IsNonSpeculative);
0xf000: rs({{
Ra = xc->readIntrFlag();
if (!xc->misspeculating()) {
xc->setIntrFlag(1);
}
}});
xc->setIntrFlag(1);
}}, IsNonSpeculative);
}
#else
format FailUnimpl {
@@ -2449,38 +2434,26 @@ decode OPCODE default Unknown::unknown() {
fault = Unimplemented_Opcode_Fault;
}
else {
bool dopal = true;
// check to see if simulator wants to do something special
// on this PAL call (including maybe suppress it)
bool dopal = xc->simPalCheck(palFunc);
if (!xc->misspeculating()) {
// check to see if simulator wants to do something special
// on this PAL call (including maybe suppress it)
dopal = xc->simPalCheck(palFunc);
if (dopal) {
AlphaISA::swap_palshadow(&xc->xcBase()->regs, true);
xc->setIpr(AlphaISA::IPR_EXC_ADDR, NPC);
}
}
// if we're misspeculating, it's still safe (if
// unrealistic) to set NPC, as the control-flow change
// won't get committed.
if (dopal) {
AlphaISA::swap_palshadow(&xc->xcBase()->regs, true);
xc->setIpr(AlphaISA::IPR_EXC_ADDR, NPC);
NPC = xc->readIpr(AlphaISA::IPR_PAL_BASE, fault) + palOffset;
}
}
}});
}}, IsNonSpeculative);
#else
0x00: decode PALFUNC {
format EmulatedCallPal {
0x00: halt ({{
if (!xc->misspeculating())
SimExit(curTick, "halt instruction encountered");
}});
SimExit(curTick, "halt instruction encountered");
}}, IsNonSpeculative);
0x83: callsys({{
if (!xc->misspeculating())
xc->syscall();
}});
xc->syscall();
}}, IsNonSpeculative);
// Read uniq reg into ABI return value register (r0)
0x9e: rduniq({{ R0 = Runiq; }});
// Write uniq reg with value from ABI arg register (r16)
@@ -2514,46 +2487,36 @@ decode OPCODE default Unknown::unknown() {
// M5 special opcodes use the reserved 0x01 opcode space
0x01: decode M5FUNC {
0x00: arm({{
if (!xc->misspeculating())
AlphaPseudo::arm(xc->xcBase());
}});
AlphaPseudo::arm(xc->xcBase());
}}, IsNonSpeculative);
0x01: quiesce({{
if (!xc->misspeculating())
AlphaPseudo::quiesce(xc->xcBase());
}});
AlphaPseudo::quiesce(xc->xcBase());
}}, IsNonSpeculative);
0x10: ivlb({{
if (!xc->misspeculating())
AlphaPseudo::ivlb(xc->xcBase());
}}, No_OpClass);
AlphaPseudo::ivlb(xc->xcBase());
}}, No_OpClass, IsNonSpeculative);
0x11: ivle({{
if (!xc->misspeculating())
AlphaPseudo::ivle(xc->xcBase());
}}, No_OpClass);
AlphaPseudo::ivle(xc->xcBase());
}}, No_OpClass, IsNonSpeculative);
0x20: m5exit_old({{
if (!xc->misspeculating())
AlphaPseudo::m5exit_old(xc->xcBase());
}}, No_OpClass);
AlphaPseudo::m5exit_old(xc->xcBase());
}}, No_OpClass, IsNonSpeculative);
0x21: m5exit({{
if (!xc->misspeculating())
AlphaPseudo::m5exit(xc->xcBase());
}}, No_OpClass);
AlphaPseudo::m5exit(xc->xcBase());
}}, No_OpClass, IsNonSpeculative);
0x30: initparam({{ Ra = xc->xcBase()->cpu->system->init_param; }});
0x40: resetstats({{
if (!xc->misspeculating())
AlphaPseudo::resetstats(xc->xcBase());
}});
AlphaPseudo::resetstats(xc->xcBase());
}}, IsNonSpeculative);
0x41: dumpstats({{
if (!xc->misspeculating())
AlphaPseudo::dumpstats(xc->xcBase());
}});
AlphaPseudo::dumpstats(xc->xcBase());
}}, IsNonSpeculative);
0x42: dumpresetstats({{
if (!xc->misspeculating())
AlphaPseudo::dumpresetstats(xc->xcBase());
}});
AlphaPseudo::dumpresetstats(xc->xcBase());
}}, IsNonSpeculative);
0x43: m5checkpoint({{
if (!xc->misspeculating())
AlphaPseudo::m5checkpoint(xc->xcBase());
}});
AlphaPseudo::m5checkpoint(xc->xcBase());
}}, IsNonSpeculative);
}
}

5
cpu/static_inst.hh
View File

@@ -106,11 +106,13 @@ class StaticInstBase : public RefCounted
IsThreadSync, ///< Thread synchronization operation.
IsSerializing, ///< Serializes pipeline: won't until all
IsSerializing, ///< Serializes pipeline: won't execute until all
/// older instructions have committed.
IsMemBarrier, ///< Is a memory barrier
IsWriteBarrier, ///< Is a write barrier
IsNonSpeculative, ///< Should not be executed speculatively
NumFlags
};
@@ -192,6 +194,7 @@ class StaticInstBase : public RefCounted
bool isSerializing() const { return flags[IsSerializing]; }
bool isMemBarrier() const { return flags[IsMemBarrier]; }
bool isWriteBarrier() const { return flags[IsWriteBarrier]; }
bool isNonSpeculative() const { return flags[IsNonSpeculative]; }
//@}
/// Operation class. Used to select appropriate function unit in issue.