Adding Simple Framework for Creating Test ELFs (#29)

Created a framework for building RISC-V assembly tests for testing
Atlas. The framework uses magic memory to end simulation, which has not
been implemented in Atlas yet, so the `stop_sim_on_wfi` parameter is
required for these tests to end properly.

Created ELFs used in Atlas's regression should be checked in to the
`test/sim/workloads`dir.

sim/atlas.cpp

@@ -2,7 +2,8 @@
 
 #include "sparta/app/CommandLineSimulator.hpp"
 
-const char USAGE[] = "TODO"
+const char USAGE[] = "Usage:\n"
+                     "./atlas [-i inst limit] <workload>"
                      "\n";
 
 int main(int argc, char** argv)
@@ -49,28 +50,30 @@ int main(int argc, char** argv)
             return err_code; // Any errors already printed to cerr
         }
 
-        if (workload.empty())
-        {
-            std::cerr << "ERROR: Missing a workload to run. Provide an ELF or JSON to run"
-                      << std::endl;
-            std::cerr << USAGE;
-            return -1;
-        }
-
         // Create the simulator
         sparta::Scheduler scheduler;
         atlas::AtlasSim sim(&scheduler, workload, ilimit);
 
         cls.populateSimulation(&sim);
 
-        cls.runSimulator(&sim);
+        if (workload.empty() == false)
+        {
+            cls.runSimulator(&sim);
 
-        cls.postProcess(&sim);
+            cls.postProcess(&sim);
 
-        // Get workload exit code
-        const atlas::AtlasState::SimState* sim_state = sim.getAtlasState()->getSimState();
-        exit_code = sim_state->workload_exit_code;
-        std::cout << "Workload exit code: " << std::dec << exit_code << std::endl;
+            // Get workload exit code
+            const atlas::AtlasState::SimState* sim_state = sim.getAtlasState()->getSimState();
+            exit_code = sim_state->workload_exit_code;
+            std::cout << "Workload exit code: " << std::dec << exit_code << std::endl;
+        }
+        else
+        {
+            std::cout << "ERROR: Missing a workload to run. Provide an ELF or JSON to run"
+                      << std::endl;
+            std::cout << USAGE;
+            return 0;
+        }
     }
     catch (...)
     {

test/elfs/CMakeLists.txt

@@ -0,0 +1,45 @@
+cmake_minimum_required(VERSION 3.27.6)
+
+project(riscv_assembly_tests ASM)
+
+# Unset these variables to prevent include of Mac SDK
+set(CMAKE_OSX_SYSROOT "/")
+set(CMAKE_OSX_DEPLOYMENT_TARGET "")
+
+if(NOT RISCV_TOOLCHAIN)
+  message(FATAL_ERROR "You must supply a -DRISCV_TOOLCHAIN=/path")
+else()
+  message("-- Using RISCV_TOOLCHAIN: ${RISCV_TOOLCHAIN}")
+  if(EXISTS ${RISCV_TOOLCHAIN}/bin/riscv64-unknown-elf-as)
+    set(CMAKE_ASM_COMPILER "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-elf-as")
+    set(CMAKE_C_COMPILER   "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-elf-gcc")
+    set(CMAKE_CXX_COMPILER "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-elf-g++")
+    set(CMAKE_LINKER       "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-elf-ld")
+  elseif(EXISTS ${RISCV_TOOLCHAIN}//bin/riscv64-unknown-linux-gnu-as)
+    set(CMAKE_ASM_COMPILER "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-linux-gnu-as")
+    set(CMAKE_C_COMPILER   "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-linux-gnu-gcc")
+    set(CMAKE_CXX_COMPILER "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-linux-gnu-g++")
+    set(CMAKE_LINKER       "${RISCV_TOOLCHAIN}/bin/riscv64-unknown-linux-gnu-ld")
+  else()
+    message(FATAL_ERROR "Cannot find tools in the given RISCV_TOOLCHAIN")
+  endif()
+endif()
+
+set(BASE_DIR ${PROJECT_SOURCE_DIR})
+
+# Don't test compilers. The riscv toolchain's linker does not support the option '-search_paths_first'
+set(CMAKE_C_COMPILER_WORKS 1)
+#set(CMAKE_C_FLAGS "-march=rv64gc")
+#set(CMAKE_LINK_C_FLAGS "")
+set(CMAKE_CXX_COMPILER_WORKS 1)
+#set(CMAKE_CXX_FLAGS "-march=rv64gc")
+#set(CMAKE_LINK_CXX_FLAGS "")
+
+# Linker setup
+set(LINKER_SCRIPT ${BASE_DIR}/common/main.ld)
+set(CMAKE_ASM_LINKER_FLAGS "-T ${LINKER_SCRIPT} -e main")
+set(CMAKE_ASM_LINK_EXECUTABLE "${CMAKE_LINKER} ${CMAKE_ASM_LINKER_FLAGS} <OBJECTS> -o <TARGET>")
+
+include_directories(common)
+
+add_subdirectory(src)

test/elfs/README.md

@@ -0,0 +1,7 @@
+Build directions:
+```
+mkdir build
+cd build
+cmake .. -DRISCV_TOOLCHAIN=<path to the install of RISCV toolsuite>
+make
+```

test/elfs/common/TEST_TEMPLATE.s

@@ -0,0 +1,25 @@
+/* Test: [test name]
+ * ISA: [isa string required]
+ * Description: [description of test]
+ */
+
+.include "host.s"
+.include "macros.s"
+
+.section .text
+    .global main
+
+// Insert your test in main
+main:
+
+// Jump or fall through here if test is successful
+pass:
+    test_pass
+
+// Jump here if test is unsuccessful
+fail:
+    test_fail
+
+.section .data
+data:
+    .fill 64, 4, 0xFFFFFFFF

test/elfs/common/host.s

@@ -0,0 +1,8 @@
+.section .tohost,"aw"
+.globl tohost
+.globl fromhost
+
+tohost:
+    .dword 0
+fromhost:
+    .dword 0

test/elfs/common/macros.s

@@ -0,0 +1,26 @@
+/* Test: nop.elf
+ * ISA: rv64i
+ * Description: Stream of nops.
+ */
+
+.macro test_pass
+    li x1, 1
+    la x2, tohost
+    sw x1, 0(x2)
+    wfi
+.endm
+
+.macro test_fail
+    li x1, 2
+    la x2, tohost
+    sw x1, 0(x2)
+    wfi
+.endm
+
+.macro start_tracepoint
+     xor x0, x0, x0
+.endm
+
+.macro stop_tracepoint
+     xor x0, x1, x1
+.endm

test/elfs/common/main.ld

@@ -0,0 +1,13 @@
+OUTPUT_ARCH("riscv")
+
+SECTIONS
+{
+  . = 0x80000000;
+  .text : { *(.text) }
+  . = ALIGN(0x1000);
+  .tohost : { *(.tohost) }
+  . = ALIGN(0x1000);
+  .data : { *(.data) }
+  . = ALIGN(0x1000);
+  .bss  : { *(.bss) }
+}

test/elfs/src/CMakeLists.txt

@@ -0,0 +1,5 @@
+project (BASE_TESTS)
+
+set (CMAKE_ASM_FLAGS "-march=rv64i_zicsr_zifencei")
+
+add_subdirectory (nop)

test/elfs/src/nop/CMakeLists.txt

@@ -0,0 +1,3 @@
+project(nop_test)
+
+add_executable        (nop.elf nop.s)

test/elfs/src/nop/nop.s

@@ -0,0 +1,25 @@
+/* Test: nop.elf
+ * ISA: rv64i
+ * Description: Stream of nops.
+ */
+
+.include "host.s"
+.include "macros.s"
+
+.section .text
+    .global main
+
+main:
+    .rept 1000
+        nop
+    .endr
+
+pass:
+    test_pass
+
+fail:
+    test_fail
+
+.section .data
+data:
+    .fill 64, 4, 0xFFFFFFFF