From 3d5434022a2f97e5e855e17c8e46b08e38c8bb9e Mon Sep 17 00:00:00 2001 From: Rekai Date: Mon, 2 Mar 2015 04:00:38 -0500 Subject: cpu: o3 register renaming request handling improved Now, prior to the renaming, the instruction requests the exact amount of registers it will need, and the rename_map decides whether the instruction is allowed to proceed or not. --- src/cpu/base_dyn_inst.hh | 1 + src/cpu/o3/rename_impl.hh | 6 ++++-- src/cpu/o3/rename_map.hh | 23 +++++++++++++++++++++++ src/cpu/static_inst.hh | 3 +++ 4 files changed, 31 insertions(+), 2 deletions(-) (limited to 'src/cpu') diff --git a/src/cpu/base_dyn_inst.hh b/src/cpu/base_dyn_inst.hh index ab275369f..875cb2946 100644 --- a/src/cpu/base_dyn_inst.hh +++ b/src/cpu/base_dyn_inst.hh @@ -594,6 +594,7 @@ class BaseDynInst : public ExecContext, public RefCounted // for machines with separate int & FP reg files int8_t numFPDestRegs() const { return staticInst->numFPDestRegs(); } int8_t numIntDestRegs() const { return staticInst->numIntDestRegs(); } + int8_t numCCDestRegs() const { return staticInst->numCCDestRegs(); } /** Returns the logical register index of the i'th destination register. */ RegIndex destRegIdx(int i) const { return staticInst->destRegIdx(i); } diff --git a/src/cpu/o3/rename_impl.hh b/src/cpu/o3/rename_impl.hh index 04a9020d7..7bf33d3ff 100644 --- a/src/cpu/o3/rename_impl.hh +++ b/src/cpu/o3/rename_impl.hh @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010-2012, 2014 ARM Limited + * Copyright (c) 2010-2012, 2014-2015 ARM Limited * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved. * @@ -633,7 +633,9 @@ DefaultRename::renameInsts(ThreadID tid) // Check here to make sure there are enough destination registers // to rename to. Otherwise block. - if (renameMap[tid]->numFreeEntries() < inst->numDestRegs()) { + if (!renameMap[tid]->canRename(inst->numIntDestRegs(), + inst->numFPDestRegs(), + inst->numCCDestRegs())) { DPRINTF(Rename, "Blocking due to lack of free " "physical registers to rename to.\n"); blockThisCycle = true; diff --git a/src/cpu/o3/rename_map.hh b/src/cpu/o3/rename_map.hh index 1aa3bc702..9d91f232e 100644 --- a/src/cpu/o3/rename_map.hh +++ b/src/cpu/o3/rename_map.hh @@ -1,4 +1,16 @@ /* + * Copyright (c) 2015 ARM Limited + * All rights reserved. + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * * Copyright (c) 2004-2005 The Regents of The University of Michigan * Copyright (c) 2013 Advanced Micro Devices, Inc. * All rights reserved. @@ -346,6 +358,17 @@ class UnifiedRenameMap { return std::min(intMap.numFreeEntries(), floatMap.numFreeEntries()); } + + /** + * Return whether there are enough registers to serve the request. + */ + bool canRename(uint32_t intRegs, uint32_t floatRegs, uint32_t ccRegs) const + { + return intRegs <= intMap.numFreeEntries() && + floatRegs <= floatMap.numFreeEntries() && + ccRegs <= ccMap.numFreeEntries(); + } + }; #endif //__CPU_O3_RENAME_MAP_HH__ diff --git a/src/cpu/static_inst.hh b/src/cpu/static_inst.hh index 7206a2616..684a22856 100644 --- a/src/cpu/static_inst.hh +++ b/src/cpu/static_inst.hh @@ -117,6 +117,9 @@ class StaticInst : public RefCounted, public StaticInstFlags /// Number of integer destination regs. int8_t numIntDestRegs() const { return _numIntDestRegs; } //@} + /// Number of coprocesor destination regs. + int8_t numCCDestRegs() const { return _numCCDestRegs; } + //@} /// @name Flag accessors. /// These functions are used to access the values of the various -- cgit v1.2.3