[difftest] support ordered memory write for scalar and vector

chipsalliance · Jul 16, 2024 · fa947f7 · fa947f7
1 parent c5d77f0
commit fa947f7
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Showing 4 changed files with 34 additions and 2 deletions.
diff --git a/difftest/online_drive/dpi_c/dpi.cc b/difftest/online_drive/dpi_c/dpi.cc
@@ -91,4 +91,8 @@ void retire_vector_instruction(const svBitVecVal* retire) {
     retire_vector_instruction_rs(dpi_call_target, retire);
 }
 
+void retire_vector_memory(const svBitVecVal* retire) {
+    retire_vector_memory_rs(dpi_call_target);
+}
+
 } // extern "C"
diff --git a/difftest/online_drive/dpi_c/dpi.h b/difftest/online_drive/dpi_c/dpi.h
@@ -77,7 +77,7 @@ extern void issue_vector_instruction_rs(
     svBitVecVal *issue);
 
 extern void retire_vector_instruction_rs(
-    /// struct issue_data {
+    /// struct retire_data {
     ///   uint32_t rd;
     ///   uint32_t data;
     ///   uint32_t writeRd;
@@ -86,6 +86,12 @@ extern void retire_vector_instruction_rs(
     void *dpi_call_target,
     const svBitVecVal *retire);
 
+extern void retire_vector_memory_rs(
+    /// struct retire_data {
+    ///   bool dummy;
+    /// }
+    void *dpi_call_target);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/difftest/online_drive/src/dpi.rs b/difftest/online_drive/src/dpi.rs
@@ -237,6 +237,12 @@ unsafe extern "C" fn retire_vector_instruction_rs(target: *mut (), retire_src: *
   driver.retire_instruction(retire)
 }
 
+#[no_mangle]
+unsafe extern "C" fn retire_vector_memory_rs(target: *mut (), retire_src: *const SvBitVecVal) {
+  let driver = &mut *(target as *mut Driver);
+  driver.retire_memory();
+}
+
 //--------------------------------
 // import functions and wrappers
 //--------------------------------

diff --git a/difftest/online_drive/src/drive.rs b/difftest/online_drive/src/drive.rs
@@ -1,5 +1,6 @@
 use common::spike_runner::SpikeRunner;
 use common::MEM_SIZE;
+use spike_rs::clip;
 use spike_rs::spike_event::MemAccessRecord;
 use spike_rs::spike_event::SpikeEventType;
 use spike_rs::util::load_elf_to_buffer;
@@ -27,6 +28,7 @@ pub(crate) struct Driver {
   // driver state
   last_commit_cycle: u64,
   issued: u64,
+  vector_lsu_count: u8,
 
   shadow_mem: Vec<u8>,
 }
@@ -85,6 +87,7 @@ impl Driver {
       last_commit_cycle: 0,
 
       issued: 0,
+      vector_lsu_count: 0,
       shadow_mem: vec![0; MEM_SIZE],
     };
     self_.spike_runner.load_elf(&args.common_args.elf_file).unwrap();
@@ -292,6 +295,15 @@ impl Driver {
         se.inst_bits
       );
       self.issued += 1;
+
+      // if the instruction is a vector store/load, increment the vector_lsu_count
+      let opcode = clip(se.inst_bits, 0, 6);
+      let width = clip(se.inst_bits, 12, 14);
+      if (opcode == 0b0100111 /* store */ || opcode == 0b0000111/* load */)
+        && (width.wrapping_sub(1) & 0b100 != 0)
+      {
+        self.vector_lsu_count += 1;
+      }
       // not a fence, issue it
       IssueData {
         instruction_bits: se.inst_bits,
@@ -301,7 +313,7 @@ impl Driver {
         vl: se.vl,
         vstart: se.vstart as u32,
         vcsr: se.vcsr(),
-        meta: ISSUE_VALID,
+        meta: self.vector_lsu_count == 0,
       }
     }
   }
@@ -324,4 +336,8 @@ impl Driver {
     self.spike_runner.commit_queue.pop_back();
     self.last_commit_cycle = get_t();
   }
+
+  pub(crate) fn retire_memory(&mut self) {
+    self.vector_lsu_count -= 1;
+  }
 }