RISC-V tests in QEMU

.circleci/config.yml

@@ -246,7 +246,9 @@ commands:
             llvm-build
       - run:
           name: "Test TinyGo"
-          command: make test
+          command: |
+            make gen-device-sifive # needed for testing
+            make test
       - run:
           name: "Build TinyGo release"
           command: |

azure-pipelines.yml

@@ -52,6 +52,7 @@ jobs:
         script: |
           export PATH="/c/Go1.13/bin:$PATH:./llvm-build/bin:/c/Program Files/qemu"
           unset GOROOT
+          make gen-device-sifive # needed for testing
           make test
     - task: Bash@3
       displayName: Build TinyGo release tarball

main_test.go

@@ -55,6 +55,14 @@ func TestCompiler(t *testing.T) {
 		runPlatTests("cortex-m-qemu", matches, t)
 	})
 
+	if runtime.GOOS == "windows" || runtime.GOOS == "darwin" {
+		// Note: running only on Windows and macOS because Linux usually has an
+		// outdated QEMU version that doesn't support RISC-V yet.
+		t.Run("EmulatedHiFive1", func(t *testing.T) {
+			runPlatTests("hifive1-qemu", matches, t)
+		})
+	}
+
 	if runtime.GOOS == "linux" {
 		t.Run("ARMLinux", func(t *testing.T) {
 			runPlatTests("arm--linux-gnueabihf", matches, t)
@@ -84,6 +92,8 @@ func runPlatTests(target string, matches []string, t *testing.T) {
 			// run all tests on host
 		case target == "cortex-m-qemu":
 			// all tests are supported
+		case target == "hifive1-qemu":
+			// all tests are supported
 		default:
 			// cross-compilation of cgo is not yet supported
 			if path == filepath.Join("testdata", "cgo")+string(filepath.Separator) {
@@ -204,7 +214,11 @@ func runTest(path, target string, t *testing.T) {
 	}
 	close(runComplete)
 
-	if ranTooLong {
+	if ranTooLong && target != "hifive1-qemu" {
+		// Note: the hifive1-qemu exception is here because QEMU does
+		// not yet include the SiFive test finisher used to exit tests.
+		// https://github.com/sifive/riscv-qemu/commit/0eec372a36b7237caf16ec7c7646a202faba5fdb
+		// It's a crude hack, but it makes RISC-V testable.
 		stdout.WriteString("--- test ran too long, terminating...\n")
 	}
 

src/runtime/runtime_fe310_qemu.go

@@ -3,6 +3,7 @@
 package runtime
 
 import (
+	"device/riscv"
 	"runtime/volatile"
 	"unsafe"
 )
@@ -17,4 +18,13 @@ var timestamp timeUnit
 func abort() {
 	// Signal a successful exit.
 	testExit.Set(0x5555)
+
+	// Note: the SiFive test finisher does not seem to be implemented in QEMU
+	// 4.2 (but is included in the SiFive build of QEMU). And while the above
+	// write somehow results in exiting the process on Windows, that's not the
+	// case on macOS. Therefore, make sure to halt the process with an endless
+	// loop.
+	for {
+		riscv.Asm("wfi")
+	}
 }

targets/riscv.json

@@ -3,6 +3,7 @@
 	"goos": "linux",
 	"goarch": "arm",
 	"build-tags": ["tinygo.riscv", "baremetal", "linux", "arm"],
+	"compiler": "clang",
 	"gc": "conservative",
 	"compiler": "clang",
 	"linker": "ld.lld",
@@ -13,7 +14,8 @@
 		"-mabi=ilp32",
 		"-Os",
 		"-Werror",
-		"-nostdinc",
+		"-nostdlibinc",
+		"-Wno-macro-redefined",
 		"-fno-exceptions", "-fno-unwind-tables",
 		"-ffunction-sections", "-fdata-sections"
 	],