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Fix for squashing during a serializing instruction.

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--HG--
extra : convert_revision : 04f9131258bfb7cca1654e00273edb29bde2366b
This commit is contained in:
Gabe Black 2006-12-07 18:47:33 -05:00
parent 41051f35ac
commit 0f8fd5fd68
2 changed files with 37 additions and 7 deletions
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4
src/cpu/o3/rename.hh
View file

@ -411,6 +411,10 @@ class DefaultRename
/** Whether or not rename needs to block this cycle. */
bool blockThisCycle;
/** Whether or not rename needs to resume a serialize instruction
* after squashing. */
bool resumeSerialize;
/** The number of threads active in rename. */
unsigned numThreads;

32
src/cpu/o3/rename_impl.hh
View file

@ -43,6 +43,7 @@ DefaultRename<Impl>::DefaultRename(Params *params)
commitToRenameDelay(params->commitToRenameDelay),
renameWidth(params->renameWidth),
commitWidth(params->commitWidth),
resumeSerialize(false),
numThreads(params->numberOfThreads),
maxPhysicalRegs(params->numPhysIntRegs + params->numPhysFloatRegs)
{
@ -334,13 +335,23 @@ DefaultRename<Impl>::squash(const InstSeqNum &squash_seq_num, unsigned tid)
// If it still needs to block, the blocking should happen the next
// cycle and there should be space to hold everything due to the squash.
if (renameStatus[tid] == Blocked ||
renameStatus[tid] == Unblocking ||
renameStatus[tid] == SerializeStall) {
renameStatus[tid] == Unblocking) {
toDecode->renameUnblock[tid] = 1;
resumeSerialize = false;
serializeInst[tid] = NULL;
} else if (renameStatus[tid] == SerializeStall) {
if (serializeInst[tid]->seqNum <= squash_seq_num) {
DPRINTF(Rename, "Rename will resume serializing after squash\n");
resumeSerialize = true;
assert(serializeInst[tid]);
} else {
resumeSerialize = false;
toDecode->renameUnblock[tid] = 1;
serializeInst[tid] = NULL;
}
}
// Set the status to Squashing.
renameStatus[tid] = Squashing;
@ -477,6 +488,14 @@ DefaultRename<Impl>::rename(bool &status_change, unsigned tid)
++renameSquashCycles;
} else if (renameStatus[tid] == SerializeStall) {
++renameSerializeStallCycles;
// If we are currently in SerializeStall and resumeSerialize
// was set, then that means that we are resuming serializing
// this cycle. Tell the previous stages to block.
if (resumeSerialize) {
resumeSerialize = false;
block(tid);
toDecode->renameUnblock[tid] = false;
}
}
if (renameStatus[tid] == Running ||
@ -1245,12 +1264,19 @@ DefaultRename<Impl>::checkSignalsAndUpdate(unsigned tid)
if (renameStatus[tid] == Squashing) {
// Switch status to running if rename isn't being told to block or
// squash this cycle.
if (!resumeSerialize) {
DPRINTF(Rename, "[tid:%u]: Done squashing, switching to running.\n",
tid);
renameStatus[tid] = Running;
return false;
} else {
DPRINTF(Rename, "[tid:%u]: Done squashing, switching to serialize.\n",
tid);
renameStatus[tid] = SerializeStall;
return true;
}
}
if (renameStatus[tid] == SerializeStall) {