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cpu: Use the newly promoted uReset in the minor CPU.

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Rather than use an #if THE_ISA check to see if the CPU can use the
microPC accessirs, this change uses the newly promoted/exposed uReset
for the same purpose.

Jira Issue: https://gem5.atlassian.net/browse/GEM5-1060

Change-Id: I4ac931624a2c8e2bbcd5189a05d9ec174bd03d4a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/48705
Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This commit is contained in:
Gabe Black
2021-07-27 19:50:37 -07:00
parent db1ec14120
commit f15032fbb2
1 changed files with 11 additions and 14 deletions
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25
src/cpu/minor/fetch2.cc
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@@ -436,24 +436,21 @@ Fetch2::evaluate()
line_in->lineWidth, output_index, fetch_info.inputIndex,
fetch_info.pc, *dyn_inst);
#if THE_ISA == X86_ISA || THE_ISA == ARM_ISA
/* In SE mode, it's possible to branch to a microop when
* replaying faults such as page faults (or simply
* intra-microcode branches in X86). Unfortunately,
* as Minor has micro-op decomposition in a separate
* pipeline stage from instruction decomposition, the
* following advancePC (which may follow a branch with
* microPC() != 0) *must* see a fresh macroop. This
* kludge should be improved with an addition to PCState
* but I offer it in this form for the moment
/*
* In SE mode, it's possible to branch to a microop when
* replaying faults such as page faults (or simply
* intra-microcode branches in X86). Unfortunately,
* as Minor has micro-op decomposition in a separate
* pipeline stage from instruction decomposition, the
* following advancePC (which may follow a branch with
* microPC() != 0) *must* see a fresh macroop.
*
* X86 can branch within microops so we need to deal with
* the case that, after a branch, the first un-advanced PC
* may be pointing to a microop other than 0. Once
* advanced, however, the microop number *must* be 0 */
fetch_info.pc.upc(0);
fetch_info.pc.nupc(1);
#endif
* advanced, however, the microop number *must* be 0
*/
fetch_info.pc.uReset();
/* Advance PC for the next instruction */
decoded_inst->advancePC(fetch_info.pc);