From 7ed6d62a3c99cd82c8df9e8c887b0c87f764025a Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Tue, 14 Jan 2020 16:59:51 +0100
Subject: [PATCH 1/2] riscv: add support for CGo

This commit makes the following command work correctly:

    tinygo run -target=hifive1-qemu ./testdata/cgo/
---
 targets/riscv.json | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/targets/riscv.json b/targets/riscv.json
index f96354008d..a84e2b0189 100644
--- a/targets/riscv.json
+++ b/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"
 	],

From fedc36ef5d4c9a8bde4a6ba60adf4eddc89a5835 Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Sat, 30 Nov 2019 13:26:58 +0100
Subject: [PATCH 2/2] riscv: run tests in QEMU

These tests should make sure that things that work now won't break in
the future.
---
 .circleci/config.yml              |  4 +++-
 azure-pipelines.yml               |  1 +
 main_test.go                      | 16 +++++++++++++++-
 src/runtime/runtime_fe310_qemu.go | 10 ++++++++++
 4 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/.circleci/config.yml b/.circleci/config.yml
index dcd33dd5c9..152d5efb0b 100644
--- a/.circleci/config.yml
+++ b/.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: |
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 5b6a5c0429..c27e50cc3c 100644
--- a/azure-pipelines.yml
+++ b/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
diff --git a/main_test.go b/main_test.go
index 188f318e8d..f11af75b31 100644
--- a/main_test.go
+++ b/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")
 	}
 
diff --git a/src/runtime/runtime_fe310_qemu.go b/src/runtime/runtime_fe310_qemu.go
index 132515e795..3270aa3deb 100644
--- a/src/runtime/runtime_fe310_qemu.go
+++ b/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")
+	}
 }