Important fixes to templates blatt03

aufgaben/blatt03/BPConfig.py

@@ -3,21 +3,36 @@ from m5.objects import *
 import argparse
 import sys
 import pandas
+import shlex
 
 parser = argparse.ArgumentParser(description='Simulate benchmark')
-# parser.add_argument('--type', help='CPU Type (one of: o3, minor, timing)')
 parser.add_argument('--o3', help='use DerivO3Cpu instead of TimingSimpleCpu', action="store_true")
 parser.add_argument('-c', help='binary to execute')
 parser.add_argument('-w', help='width of pipeline') 
 parser.add_argument('-o', help='The options to pass to the binary, use " " around the entire string')
-parser.add_argument('-b', choices=['local','tournament','gas','gas_speculative'], help='branch prediction')
+parser.add_argument('-b', choices=['local','tournament','gas','gas_speculative','bht'], help='branch prediction')
 args = parser.parse_args()
 
 if args.o3:
     CPU = DerivO3CPU
+    
+    # width of pipeline configuration
+    width = 8 if args.w is None else args.w
+    CPU.decodeWidth = width # std: 8
+    CPU.commitWidth = width
+    CPU.fetchWidth = width
+    CPU.issueWidth = width
+    CPU.renameWidth = width
+    CPU.squashWidth = width
+    # CPU.wbWidth = width if (width > 8) else 8
+    CPU.fetchQueueSize = width
+
 else:
     CPU = TimingSimpleCPU
 
+
+
+
 class L1Cache(BaseCache):
     assoc = 2
     hit_latency = 2
@@ -28,18 +43,18 @@ class L1Cache(BaseCache):
     is_top_level = True
 
 
-if (args.b == 'local' org args.b == 'bht'):
+if (args.b == 'local' or args.b == 'bht'):
     CPU.branchPred = LocalBP(localPredictorSize=256,localCtrBits=2)
 elif (args.b == 'gas'):
-    CPU.branchPred = GAsBP(localPredictorSize=256, globalHistorySize=8, localCtrBits=2, speculativeUpdate=False);
+    CPU.branchPred = GAsBP(localPredictorSize=256, globalHistorySize=3, localCtrBits=2, speculativeUpdate=False);
 elif (args.b == 'gas_speculative'):
-    CPU.branchPred = GAsBP(localPredictorSize=256, globalHistorySize=8, localCtrBits=2, speculativeUpdate=True);
+    CPU.branchPred = GAsBP(localPredictorSize=256, globalHistorySize=3, localCtrBits=2, speculativeUpdate=True);
 elif (args.b == "tournament"):
     CPU.branchPred = TournamentBP(localPredictorSize=256,
                                   globalPredictorSize=256,
                                   choicePredictorSize=256)
 else:
-    CPU.branchPred = GAsBP(localPredictorSize=256, globalHistorySize=8, localCtrBits=2, speculativeUpdate=False);
+    CPU.branchPred = GAsBP(localPredictorSize=256, globalHistorySize=3, localCtrBits=2, speculativeUpdate=False);
 
 
 system = System()
@@ -74,7 +89,10 @@ system.mem_ctrl.port = system.membus.master
 
 process = LiveProcess()
 
-process.cmd = [args.c] if not args.o else [args.c]+str.split(args.o)
+process.cmd = shlex.split(args.c)
+if args.o:
+    process.cmd += shlex.split(args.o)
+print process.cmd
 system.cpu.workload = process
 system.cpu.createThreads()
 

aufgaben/blatt03/branches/branches1.c

@@ -14,5 +14,5 @@ int main () {
 	    j++;
 	} while( j < 3 );
 	i++;
-    } while( i < 1000 );
+    } while( i < 100000 );
 }

aufgaben/blatt03/gem5/src/cpu/pred/BranchPredictor.py

@@ -86,4 +86,4 @@ class GAsBP(BranchPredictor):
     localCtrBits = Param.Unsigned(2, "Bits per counter")
     speculativeUpdate = Param.Bool(False, "speculative update of GHR")
     speculativeUpdateCounters = Param.Bool(False, "speculative update of counters")
-
+    squashHistory = Param.Bool(True, "Reset speculative global History register to its previous value when mispredictions are detected")

aufgaben/blatt03/gem5/src/cpu/pred/GAsBP.cc

@@ -33,39 +33,45 @@
 #include "base/trace.hh"
 #include "cpu/pred/GAsBP.hh"
 #include "debug/Fetch.hh"
+#include <math.h>
 
 GAsBP::GAsBP(const GAsBPParams *params)
     : BPredUnit(params),
       localPredictorSize(params->localPredictorSize),
-      globalPredictorSize(params->globalPredictorSize),
+      globalHistorySize(params->globalHistorySize),
       localCtrBits(params->localCtrBits),
       speculativeUpdate(params->speculativeUpdate),
-      speculativeUpdateCounters(params->speculativeUpdateCounters)
+      speculativeUpdateCounters(params->speculativeUpdateCounters),
+      squashHistory(params->squashHistory)
 {
     if (!isPowerOf2(localPredictorSize)) {
         fatal("Invalid local predictor size!\n");
     }
-    
-    // if (!isPowerOf2(globalPredictorSize)) {
-    //     fatal("Invalid global history register size!\n");
-    // }
 
     localPredictorSets = localPredictorSize / localCtrBits;
 
     if (!isPowerOf2(localPredictorSets)) {
         fatal("Invalid number of local predictor sets! Check localCtrBits.\n");
     }
+
+    DPRINTF(Fetch, "global history size: %i\n", globalHistorySize);
+    
+    globalPredictorSize = std::pow(2, globalHistorySize);
+
+    DPRINTF(Fetch, "global predictor size: %i\n", globalPredictorSize);
     
     // Setup the index mask.
     indexMask = localPredictorSets - 1;
 
-    DPRINTF(Fetch, "index mask: %#x\n", indexMask);
+    DPRINTF(Fetch, "local index mask: %#x\n", indexMask);
 
     // Setup the global history register and mask
     globalHistoryBits = 0;
     globalHistoryBitsSpeculative = 0;
     globalHistoryMask = globalPredictorSize - 1;
 
+    DPRINTF(Fetch, "global index mask: %i\n", globalHistoryMask);
+
     // Setup the array of counters for the local predictor and the global history register.
     localCtrs.resize(localPredictorSets);
     for (unsigned i = 0; i < localPredictorSets; ++i) 
@@ -113,8 +119,7 @@ GAsBP::lookup(Addr branch_addr, void * &bp_history)
     if (speculativeUpdate)
 	global_history_idx = globalHistoryBitsSpeculative;
 
-    DPRINTF(Fetch, "Looking up index %#x\n",
-            local_predictor_idx);
+    DPRINTF(Fetch, "Looking up index %#x, %#x\n", local_predictor_idx, global_history_idx);
 
     counter_val = localCtrs[local_predictor_idx][global_history_idx].read();
 
@@ -123,14 +128,16 @@ GAsBP::lookup(Addr branch_addr, void * &bp_history)
     
     taken = getPrediction(counter_val);
     
-    // Spekulatives update des globalen History Registers
+    // Speculative update.
     if (speculativeUpdate) {
 	if (taken) {
-	    DPRINTF(Fetch, "Speculative update as taken.\n");
+	    DPRINTF(Fetch, "Branch speculative updated as taken.\n");
 	    //A2: Fall 1 vorhersage taken
+
 	} else {
-	    DPRINTF(Fetch, "Speculative update as not taken.\n");
+	    DPRINTF(Fetch, "Branch speculative updated as not taken.\n");
 	    //A2: Fall 2 vorhersage not taken
+
 	}
        globalHistoryBitsSpeculative &= globalHistoryMask;
     }
@@ -149,21 +156,24 @@ GAsBP::update(Addr branch_addr, bool taken, void *bp_history, bool squashed)
     local_predictor_idx = getLocalIndex(branch_addr);
     global_history_idx = globalHistoryBits;
 
-    DPRINTF(Fetch, "Looking up index %#x\n", local_predictor_idx);
-    
+    DPRINTF(Fetch, "Updating index %#x, %#x\n", local_predictor_idx, global_history_idx);    
     if (taken) {
         DPRINTF(Fetch, "Branch updated as taken.\n");
-	///A1: Update des Branch Predictors im Fall taken
+	//A1: Update des Branch Predictors im Fall taken
 
     } else {
         DPRINTF(Fetch, "Branch updated as not taken.\n");
-	///A1: Update des Branch Predictors im Fall not taken
+	//A1: Update des Branch Predictors im Fall not taken
+
     }
     globalHistoryBits &= globalHistoryMask;
 
-    if (squashed) {
-	DPRINTF(Fetch, "Squashed resetting speculative global history\n");
-	//A2 (bonus): Wie kann mit diesen Fehlvorhersagen umgegangen werden
+    if (squashed && squashHistory) {
+      DPRINTF(Fetch, "Squashed  %i, %i\n", 
+	      globalHistoryBitsSpeculative,
+	      globalHistoryBits);
+      //A2 (bonus): Wie kann mit diesen Fehlvorhersagen umgegangen werden
+    
     }
 }
 

aufgaben/blatt03/gem5/src/cpu/pred/GAsBP.hh

@@ -114,7 +114,10 @@ class GAsBP : public BPredUnit
     std::vector< std::vector<SatCounter> > localCtrs;
 
     /** Size of the local predictor. */
-    unsigned localPredictorySize;
+    unsigned localPredictorSize;
+
+    /** Size of the global predictor. */
+    unsigned globalPredictorSize;
 
     /** Size of the global history register. */
     unsigned globalHistorySize;
@@ -138,6 +141,9 @@ class GAsBP : public BPredUnit
 
     /** constant to enable speculative update in counters */
     bool speculativeUpdateCounters;
+
+  /** Reset speculative global History register to its previous value when mispredictions are detected*/
+    bool squashHistory;
 };
 
 #endif // __CPU_PRED_GAS_PRED_HH__