Lsu allow spec load exec (riscv-software-src#92)

This PR introduces the following - Allows loads to perform Virtual address to Physical address translation before older loads complete This can be configured using a parameter in the LSU (`allow_speculative_load_exec`) - Allow non blocking cache lookup requests. Depends on riscv-software-src#91 for the cache to support this feature - Implements Ready queue - simulator-only structure to speed up instruction lookup in the LSU - Mitigates data hazards introduced by instructions running out of order - The length of the different stages of the LSU pipeline can be configured through the parameters. --------- Co-authored-by: Knute Lingaard <[email protected]>
LiGaOg · Dec 19, 2023 · 30b7961 · 30b7961
1 parent 38d41e4
commit 30b7961
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diff --git a/.clang-format b/.clang-format
@@ -138,7 +138,6 @@ ReflowComments:  true
 RemoveBracesLLVM: false
 SeparateDefinitionBlocks: Always
 ShortNamespaceLines: 1
-SortIncludes:    CaseSensitive
 SortJavaStaticImport: Before
 SortUsingDeclarations: true
 SpaceAfterCStyleCast: false

diff --git a/.github/workflows/ubuntu-build.yml b/.github/workflows/ubuntu-build.yml
@@ -16,7 +16,7 @@ jobs:
         BUILD_TYPE: [Debug,Release]
         COMPILER: [gcc,clang]
 
-    name: Ubuntu-${{ matrix.BUILD_TYPE }}
+    name: Ubuntu-${{ matrix.BUILD_TYPE }}-${{matrix.COMPILER}}
     runs-on: ${{ matrix.os }}
 
     # Set up a global environment variable for build scripts

diff --git a/core/DCache.hpp b/core/DCache.hpp
@@ -10,12 +10,15 @@
 #include "cache/TreePLRUReplacement.hpp"
 #include "MemoryAccessInfo.hpp"
 
-namespace olympia {
-    class DCache : public sparta::Unit {
-    public:
-        class CacheParameterSet : public sparta::ParameterSet {
-        public:
-            CacheParameterSet(sparta::TreeNode *n) : sparta::ParameterSet(n) {}
+namespace olympia
+{
+    class DCache : public sparta::Unit
+    {
+      public:
+        class CacheParameterSet : public sparta::ParameterSet
+        {
+          public:
+            CacheParameterSet(sparta::TreeNode* n) : sparta::ParameterSet(n) {}
 
             // Parameters for the DL1 cache
             PARAMETER(uint32_t, l1_line_size, 64, "DL1 line size (power of 2)")
@@ -26,24 +29,24 @@ namespace olympia {
         };
 
         static const char name[];
-        DCache(sparta::TreeNode *n, const CacheParameterSet *p);
+        DCache(sparta::TreeNode* n, const CacheParameterSet* p);
 
-    private:
-        bool dataLookup_(const MemoryAccessInfoPtr &mem_access_info_ptr);
+      private:
+        bool dataLookup_(const MemoryAccessInfoPtr & mem_access_info_ptr);
 
         void reloadCache_(uint64_t phy_addr);
 
-        void getInstsFromLSU_(const MemoryAccessInfoPtr &memory_access_info_ptr);
+        void getInstsFromLSU_(const MemoryAccessInfoPtr & memory_access_info_ptr);
 
-        void getAckFromL2Cache_(const uint32_t &ack);
+        void getAckFromL2Cache_(const uint32_t & ack);
 
-        void getRespFromL2Cache_(const InstPtr &inst_ptr);
+        void getRespFromL2Cache_(const InstPtr & inst_ptr);
 
         using L1Handle = CacheFuncModel::Handle;
         L1Handle l1_cache_;
         const bool l1_always_hit_;
-        bool busy_;
-        uint32_t cache_latency_;
+        bool busy_ = false;
+        uint32_t cache_latency_ = 0;
         // Keep track of the instruction that causes current outstanding cache miss
         MemoryAccessInfoPtr cache_pending_inst_ = nullptr;
 
@@ -53,29 +56,25 @@ namespace olympia {
         ////////////////////////////////////////////////////////////////////////////////
         // Input Ports
         ////////////////////////////////////////////////////////////////////////////////
-        sparta::DataInPort<MemoryAccessInfoPtr> in_lsu_lookup_req_
-                {&unit_port_set_, "in_lsu_lookup_req", 0};
+        sparta::DataInPort<MemoryAccessInfoPtr> in_lsu_lookup_req_{&unit_port_set_,
+                                                                   "in_lsu_lookup_req", 0};
 
-        sparta::DataInPort<uint32_t> in_l2cache_ack_
-                {&unit_port_set_, "in_l2cache_ack", 1};
+        sparta::DataInPort<uint32_t> in_l2cache_ack_{&unit_port_set_, "in_l2cache_ack", 1};
 
-        sparta::DataInPort<InstPtr> in_l2cache_resp_
-                {&unit_port_set_, "in_l2cache_resp", 1};
+        sparta::DataInPort<InstPtr> in_l2cache_resp_{&unit_port_set_, "in_l2cache_resp", 1};
 
         ////////////////////////////////////////////////////////////////////////////////
         // Output Ports
         ////////////////////////////////////////////////////////////////////////////////
-        sparta::SignalOutPort out_lsu_free_req_
-                {&unit_port_set_, "out_lsu_free_req", 0};
+        sparta::SignalOutPort out_lsu_free_req_{&unit_port_set_, "out_lsu_free_req", 0};
 
-        sparta::DataOutPort<MemoryAccessInfoPtr> out_lsu_lookup_ack_
-                {&unit_port_set_, "out_lsu_lookup_ack", 0};
+        sparta::DataOutPort<MemoryAccessInfoPtr> out_lsu_lookup_ack_{&unit_port_set_,
+                                                                     "out_lsu_lookup_ack", 0};
 
-        sparta::DataOutPort<MemoryAccessInfoPtr> out_lsu_lookup_req_
-                {&unit_port_set_, "out_lsu_lookup_req", 1};
+        sparta::DataOutPort<MemoryAccessInfoPtr> out_lsu_lookup_req_{&unit_port_set_,
+                                                                     "out_lsu_lookup_req", 1};
 
-        sparta::DataOutPort<InstPtr> out_l2cache_req_
-                {&unit_port_set_, "out_l2cache_req", 0};
+        sparta::DataOutPort<InstPtr> out_l2cache_req_{&unit_port_set_, "out_l2cache_req", 0};
 
         ////////////////////////////////////////////////////////////////////////////////
         // Events
@@ -84,15 +83,12 @@ namespace olympia {
         ////////////////////////////////////////////////////////////////////////////////
         // Counters
         ////////////////////////////////////////////////////////////////////////////////
-        sparta::Counter dl1_cache_hits_{
-                getStatisticSet(), "dl1_cache_hits",
-                "Number of DL1 cache hits", sparta::Counter::COUNT_NORMAL
-        };
+        sparta::Counter dl1_cache_hits_{getStatisticSet(), "dl1_cache_hits",
+                                        "Number of DL1 cache hits", sparta::Counter::COUNT_NORMAL};
 
-        sparta::Counter dl1_cache_misses_{
-                getStatisticSet(), "dl1_cache_misses",
-                "Number of DL1 cache misses", sparta::Counter::COUNT_NORMAL
-        };
+        sparta::Counter dl1_cache_misses_{getStatisticSet(), "dl1_cache_misses",
+                                          "Number of DL1 cache misses",
+                                          sparta::Counter::COUNT_NORMAL};
     };
 
-}
+} // namespace olympia
diff --git a/core/Decode.cpp b/core/Decode.cpp
@@ -84,7 +84,7 @@ namespace olympia
             for(uint32_t i = 0; i < num_decode; ++i) {
                 const auto & inst = fetch_queue_.read(0);
                 insts->emplace_back(inst);
-                inst->setStatus(Inst::Status::RENAMED);
+                inst->setStatus(Inst::Status::DECODED);
 
                 ILOG("Decoded: " << inst);
 

diff --git a/core/Inst.hpp b/core/Inst.hpp
@@ -114,6 +114,12 @@ namespace olympia
         }
 
         void setStatus(Status status) {
+            sparta_assert(status_state_ != status,
+                          "Status being set twice to the same value: "
+                          << status << " " << *this);
+            sparta_assert(status > status_state_,
+                          "Cannot go backwards in status.  Current: "
+                          << status_state_ << " New: " << status << *this);
             status_state_ = status;
             if(getStatus() == Status::COMPLETED) {
                 if(ev_retire_ != 0) {