purego: add support for ppc64le

.github/workflows/test.yml

@@ -8,6 +8,7 @@ jobs:
       matrix:
         os: [ubuntu-latest, ubuntu-24.04-arm, macos-latest, windows-latest]
         go: ['1.18.x', '1.19.x', '1.20.x', '1.21.x', '1.22.x', '1.23.x', '1.24.x', '1.25.x', '1.26.0-rc.2']
+      fail-fast: false
     name: Test with Go ${{ matrix.go }} on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     defaults:
@@ -140,6 +141,20 @@ jobs:
            go env -u CC
            go env -u CXX
 
+      - name: go test (Linux ppc64le)
+        if: ${{ runner.os == 'Linux' && runner.arch != 'ARM64' && !startsWith(matrix.go, '1.18.') && !startsWith(matrix.go, '1.19.') && !startsWith(matrix.go, '1.20.') && !startsWith(matrix.go, '1.21.') }}
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y gcc-powerpc64le-linux-gnu g++-powerpc64le-linux-gnu qemu-user
+          go env -w CC=powerpc64le-linux-gnu-gcc
+          go env -w CXX=powerpc64le-linux-gnu-g++
+          env GOOS=linux GOARCH=ppc64le CGO_ENABLED=0 go test -c -o=purego-test-nocgo .
+          env QEMU_LD_PREFIX=/usr/powerpc64le-linux-gnu qemu-ppc64le ./purego-test-nocgo -test.shuffle=on -test.v -test.count=10
+          env GOOS=linux GOARCH=ppc64le CGO_ENABLED=1 go test -c -o=purego-test-cgo .
+          env QEMU_LD_PREFIX=/usr/powerpc64le-linux-gnu qemu-ppc64le ./purego-test-cgo -test.shuffle=on -test.v -test.count=10
+          go env -u CC
+          go env -u CXX
+
       - name: go test (Linux riscv64)
         if: ${{ runner.os == 'Linux' && runner.arch != 'ARM64' && !startsWith(matrix.go, '1.18.') && !startsWith(matrix.go, '1.19.') && !startsWith(matrix.go, '1.20.') && !startsWith(matrix.go, '1.21.') }}
         run: |

README.md

@@ -42,7 +42,7 @@ Tier 2 platforms are supported by PureGo on a best-effort basis. Critical bugs o
 
 - **Android**: 386<sup>1</sup>, arm<sup>1</sup>
 - **FreeBSD**: amd64<sup>2</sup>, arm64<sup>2</sup>
-- **Linux**: 386, arm, loong64, riscv64
+- **Linux**: 386, arm, loong64, ppc64le, riscv64
 - **Windows**: 386<sup>3</sup>, arm<sup>3,4</sup>
 
 #### Support Notes

abi_ppc64x.h

@@ -0,0 +1,195 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Macros for transitioning from the host ABI to Go ABI
+//
+// On PPC64/ELFv2 targets, the following registers are callee
+// saved when called from C. They must be preserved before
+// calling into Go which does not preserve any of them.
+//
+//	R14-R31
+//	CR2-4
+//	VR20-31
+//	F14-F31
+//
+// xcoff(aix) and ELFv1 are similar, but may only require a
+// subset of these.
+//
+// These macros assume a 16 byte aligned stack pointer. This
+// is required by ELFv1, ELFv2, and AIX PPC64.
+
+#define SAVE_GPR_SIZE (18*8)
+#define SAVE_GPR(offset)               \
+	MOVD	R14, (offset+8*0)(R1)  \
+	MOVD	R15, (offset+8*1)(R1)  \
+	MOVD	R16, (offset+8*2)(R1)  \
+	MOVD	R17, (offset+8*3)(R1)  \
+	MOVD	R18, (offset+8*4)(R1)  \
+	MOVD	R19, (offset+8*5)(R1)  \
+	MOVD	R20, (offset+8*6)(R1)  \
+	MOVD	R21, (offset+8*7)(R1)  \
+	MOVD	R22, (offset+8*8)(R1)  \
+	MOVD	R23, (offset+8*9)(R1)  \
+	MOVD	R24, (offset+8*10)(R1) \
+	MOVD	R25, (offset+8*11)(R1) \
+	MOVD	R26, (offset+8*12)(R1) \
+	MOVD	R27, (offset+8*13)(R1) \
+	MOVD	R28, (offset+8*14)(R1) \
+	MOVD	R29, (offset+8*15)(R1) \
+	MOVD	g,   (offset+8*16)(R1) \
+	MOVD	R31, (offset+8*17)(R1)
+
+#define RESTORE_GPR(offset)            \
+	MOVD	(offset+8*0)(R1), R14  \
+	MOVD	(offset+8*1)(R1), R15  \
+	MOVD	(offset+8*2)(R1), R16  \
+	MOVD	(offset+8*3)(R1), R17  \
+	MOVD	(offset+8*4)(R1), R18  \
+	MOVD	(offset+8*5)(R1), R19  \
+	MOVD	(offset+8*6)(R1), R20  \
+	MOVD	(offset+8*7)(R1), R21  \
+	MOVD	(offset+8*8)(R1), R22  \
+	MOVD	(offset+8*9)(R1), R23  \
+	MOVD	(offset+8*10)(R1), R24 \
+	MOVD	(offset+8*11)(R1), R25 \
+	MOVD	(offset+8*12)(R1), R26 \
+	MOVD	(offset+8*13)(R1), R27 \
+	MOVD	(offset+8*14)(R1), R28 \
+	MOVD	(offset+8*15)(R1), R29 \
+	MOVD	(offset+8*16)(R1), g   \
+	MOVD	(offset+8*17)(R1), R31
+
+#define SAVE_FPR_SIZE (18*8)
+#define SAVE_FPR(offset)               \
+	FMOVD	F14, (offset+8*0)(R1)  \
+	FMOVD	F15, (offset+8*1)(R1)  \
+	FMOVD	F16, (offset+8*2)(R1)  \
+	FMOVD	F17, (offset+8*3)(R1)  \
+	FMOVD	F18, (offset+8*4)(R1)  \
+	FMOVD	F19, (offset+8*5)(R1)  \
+	FMOVD	F20, (offset+8*6)(R1)  \
+	FMOVD	F21, (offset+8*7)(R1)  \
+	FMOVD	F22, (offset+8*8)(R1)  \
+	FMOVD	F23, (offset+8*9)(R1)  \
+	FMOVD	F24, (offset+8*10)(R1) \
+	FMOVD	F25, (offset+8*11)(R1) \
+	FMOVD	F26, (offset+8*12)(R1) \
+	FMOVD	F27, (offset+8*13)(R1) \
+	FMOVD	F28, (offset+8*14)(R1) \
+	FMOVD	F29, (offset+8*15)(R1) \
+	FMOVD	F30, (offset+8*16)(R1) \
+	FMOVD	F31, (offset+8*17)(R1)
+
+#define RESTORE_FPR(offset)            \
+	FMOVD	(offset+8*0)(R1), F14  \
+	FMOVD	(offset+8*1)(R1), F15  \
+	FMOVD	(offset+8*2)(R1), F16  \
+	FMOVD	(offset+8*3)(R1), F17  \
+	FMOVD	(offset+8*4)(R1), F18  \
+	FMOVD	(offset+8*5)(R1), F19  \
+	FMOVD	(offset+8*6)(R1), F20  \
+	FMOVD	(offset+8*7)(R1), F21  \
+	FMOVD	(offset+8*8)(R1), F22  \
+	FMOVD	(offset+8*9)(R1), F23  \
+	FMOVD	(offset+8*10)(R1), F24 \
+	FMOVD	(offset+8*11)(R1), F25 \
+	FMOVD	(offset+8*12)(R1), F26 \
+	FMOVD	(offset+8*13)(R1), F27 \
+	FMOVD	(offset+8*14)(R1), F28 \
+	FMOVD	(offset+8*15)(R1), F29 \
+	FMOVD	(offset+8*16)(R1), F30 \
+	FMOVD	(offset+8*17)(R1), F31
+
+// Save and restore VR20-31 (aka VSR56-63). These
+// macros must point to a 16B aligned offset.
+#define SAVE_VR_SIZE (12*16)
+#define SAVE_VR(offset, rtmp)         \
+	MOVD	$(offset+16*0), rtmp  \
+	STVX	V20, (rtmp)(R1)       \
+	MOVD	$(offset+16*1), rtmp  \
+	STVX	V21, (rtmp)(R1)       \
+	MOVD	$(offset+16*2), rtmp  \
+	STVX	V22, (rtmp)(R1)       \
+	MOVD	$(offset+16*3), rtmp  \
+	STVX	V23, (rtmp)(R1)       \
+	MOVD	$(offset+16*4), rtmp  \
+	STVX	V24, (rtmp)(R1)       \
+	MOVD	$(offset+16*5), rtmp  \
+	STVX	V25, (rtmp)(R1)       \
+	MOVD	$(offset+16*6), rtmp  \
+	STVX	V26, (rtmp)(R1)       \
+	MOVD	$(offset+16*7), rtmp  \
+	STVX	V27, (rtmp)(R1)       \
+	MOVD	$(offset+16*8), rtmp  \
+	STVX	V28, (rtmp)(R1)       \
+	MOVD	$(offset+16*9), rtmp  \
+	STVX	V29, (rtmp)(R1)       \
+	MOVD	$(offset+16*10), rtmp \
+	STVX	V30, (rtmp)(R1)       \
+	MOVD	$(offset+16*11), rtmp \
+	STVX	V31, (rtmp)(R1)
+
+#define RESTORE_VR(offset, rtmp)      \
+	MOVD	$(offset+16*0), rtmp  \
+	LVX	(rtmp)(R1), V20       \
+	MOVD	$(offset+16*1), rtmp  \
+	LVX	(rtmp)(R1), V21       \
+	MOVD	$(offset+16*2), rtmp  \
+	LVX	(rtmp)(R1), V22       \
+	MOVD	$(offset+16*3), rtmp  \
+	LVX	(rtmp)(R1), V23       \
+	MOVD	$(offset+16*4), rtmp  \
+	LVX	(rtmp)(R1), V24       \
+	MOVD	$(offset+16*5), rtmp  \
+	LVX	(rtmp)(R1), V25       \
+	MOVD	$(offset+16*6), rtmp  \
+	LVX	(rtmp)(R1), V26       \
+	MOVD	$(offset+16*7), rtmp  \
+	LVX	(rtmp)(R1), V27       \
+	MOVD	$(offset+16*8), rtmp  \
+	LVX	(rtmp)(R1), V28       \
+	MOVD	$(offset+16*9), rtmp  \
+	LVX	(rtmp)(R1), V29       \
+	MOVD	$(offset+16*10), rtmp \
+	LVX	(rtmp)(R1), V30       \
+	MOVD	$(offset+16*11), rtmp \
+	LVX	(rtmp)(R1), V31
+
+// LR and CR are saved in the caller's frame. The callee must
+// make space for all other callee-save registers.
+#define SAVE_ALL_REG_SIZE (SAVE_GPR_SIZE+SAVE_FPR_SIZE+SAVE_VR_SIZE)
+
+// Stack a frame and save all callee-save registers following the
+// host OS's ABI. Fortunately, this is identical for AIX, ELFv1, and
+// ELFv2. All host ABIs require the stack pointer to maintain 16 byte
+// alignment, and save the callee-save registers in the same places.
+//
+// To restate, R1 is assumed to be aligned when this macro is used.
+// This assumes the caller's frame is compliant with the host ABI.
+// CR and LR are saved into the caller's frame per the host ABI.
+// R0 is initialized to $0 as expected by Go.
+#define STACK_AND_SAVE_HOST_TO_GO_ABI(extra)                       \
+	MOVD	LR, R0                                             \
+	MOVD	R0, 16(R1)                                         \
+	MOVW	CR, R0                                             \
+	MOVD	R0, 8(R1)                                          \
+	MOVDU	R1, -(extra)-FIXED_FRAME-SAVE_ALL_REG_SIZE(R1)     \
+	SAVE_GPR(extra+FIXED_FRAME)                                \
+	SAVE_FPR(extra+FIXED_FRAME+SAVE_GPR_SIZE)                  \
+	SAVE_VR(extra+FIXED_FRAME+SAVE_GPR_SIZE+SAVE_FPR_SIZE, R0) \
+	MOVD	$0, R0
+
+// This unstacks the frame, restoring all callee-save registers
+// as saved by STACK_AND_SAVE_HOST_TO_GO_ABI.
+//
+// R0 is not guaranteed to contain $0 after this macro.
+#define UNSTACK_AND_RESTORE_GO_TO_HOST_ABI(extra)                     \
+	RESTORE_GPR(extra+FIXED_FRAME)                                \
+	RESTORE_FPR(extra+FIXED_FRAME+SAVE_GPR_SIZE)                  \
+	RESTORE_VR(extra+FIXED_FRAME+SAVE_GPR_SIZE+SAVE_FPR_SIZE, R0) \
+	ADD 	$(extra+FIXED_FRAME+SAVE_ALL_REG_SIZE), R1            \
+	MOVD	16(R1), R0                                            \
+	MOVD	R0, LR                                                \
+	MOVD	8(R1), R0                                             \
+	MOVW	R0, CR

callback_test.go

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0
 // SPDX-FileCopyrightText: 2023 The Ebitengine Authors
 
-//go:build darwin || (linux && (386 || amd64 || arm || arm64 || loong64 || riscv64))
+//go:build darwin || (linux && (386 || amd64 || arm || arm64 || loong64 || ppc64le || riscv64))
 
 package purego_test
 

func.go

@@ -133,7 +133,7 @@ func RegisterFunc(fptr any, cfn uintptr) {
 		panic("purego: cfn is nil")
 	}
 	if ty.NumOut() == 1 && (ty.Out(0).Kind() == reflect.Float32 || ty.Out(0).Kind() == reflect.Float64) &&
-		runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "riscv64" {
+		runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "ppc64le" && runtime.GOARCH != "riscv64" {
 		panic("purego: float returns are not supported")
 	}
 	{
@@ -277,7 +277,7 @@ func RegisterFunc(fptr any, cfn uintptr) {
 		var arm64_r8 uintptr
 		if ty.NumOut() == 1 && ty.Out(0).Kind() == reflect.Struct {
 			outType := ty.Out(0)
-			if (runtime.GOARCH == "amd64" || runtime.GOARCH == "loong64" || runtime.GOARCH == "riscv64") && outType.Size() > maxRegAllocStructSize {
+			if (runtime.GOARCH == "amd64" || runtime.GOARCH == "loong64" || runtime.GOARCH == "ppc64le" || runtime.GOARCH == "riscv64") && outType.Size() > maxRegAllocStructSize {
 				val := reflect.New(outType)
 				keepAlive = append(keepAlive, val)
 				addInt(val.Pointer())
@@ -317,7 +317,7 @@ func RegisterFunc(fptr any, cfn uintptr) {
 		syscall := thePool.Get().(*syscall15Args)
 		defer thePool.Put(syscall)
 
-		if runtime.GOARCH == "loong64" || runtime.GOARCH == "riscv64" {
+		if runtime.GOARCH == "loong64" || runtime.GOARCH == "ppc64le" || runtime.GOARCH == "riscv64" {
 			syscall.Set(cfn, sysargs[:], floats[:], 0)
 			runtime_cgocall(syscall15XABI0, unsafe.Pointer(syscall))
 		} else if runtime.GOARCH == "arm64" || runtime.GOOS != "windows" {
@@ -359,9 +359,13 @@ func RegisterFunc(fptr any, cfn uintptr) {
 			// NOTE: syscall.r2 is only the floating return value on 64bit platforms.
 			// On 32bit platforms syscall.r2 is the upper part of a 64bit return.
 			// On 386, x87 FPU returns floats as float64 in ST(0), so we read as float64 and convert.
-			if runtime.GOARCH == "386" {
+			// On PPC64LE, C ABI converts float32 to double in FPR, so we read as float64.
+			switch runtime.GOARCH {
+			case "386":
 				v.SetFloat(math.Float64frombits(uint64(syscall.f1) | (uint64(syscall.f2) << 32)))
-			} else {
+			case "ppc64le":
+				v.SetFloat(math.Float64frombits(uint64(syscall.f1)))
+			default:
 				v.SetFloat(float64(math.Float32frombits(uint32(syscall.f1))))
 			}
 		case reflect.Float64:
@@ -486,7 +490,7 @@ func roundUpTo8(val uintptr) uintptr {
 
 func numOfFloatRegisters() int {
 	switch runtime.GOARCH {
-	case "amd64", "arm64", "loong64", "riscv64":
+	case "amd64", "arm64", "loong64", "ppc64le", "riscv64":
 		return 8
 	case "arm":
 		return 16
@@ -502,7 +506,7 @@ func numOfFloatRegisters() int {
 
 func numOfIntegerRegisters() int {
 	switch runtime.GOARCH {
-	case "arm64", "loong64", "riscv64":
+	case "arm64", "loong64", "ppc64le", "riscv64":
 		return 8
 	case "amd64":
 		return 6

func_test.go

@@ -50,7 +50,7 @@ func TestRegisterFunc(t *testing.T) {
 }
 
 func Test_qsort(t *testing.T) {
-	if runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "riscv64" {
+	if runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "ppc64le" && runtime.GOARCH != "riscv64" {
 		t.Skip("Platform doesn't support Floats")
 		return
 	}
@@ -79,7 +79,7 @@ func Test_qsort(t *testing.T) {
 }
 
 func TestRegisterFunc_Floats(t *testing.T) {
-	if runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "riscv64" {
+	if runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "ppc64le" && runtime.GOARCH != "riscv64" {
 		t.Skip("Platform doesn't support Floats")
 		return
 	}
@@ -121,7 +121,7 @@ func TestRegisterFunc_Floats(t *testing.T) {
 }
 
 func TestRegisterLibFunc_Bool(t *testing.T) {
-	if runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "riscv64" {
+	if runtime.GOARCH != "arm" && runtime.GOARCH != "arm64" && runtime.GOARCH != "386" && runtime.GOARCH != "amd64" && runtime.GOARCH != "loong64" && runtime.GOARCH != "ppc64le" && runtime.GOARCH != "riscv64" {
 		t.Skip("Platform doesn't support callbacks")
 		return
 	}
@@ -376,7 +376,7 @@ func TestABI_ArgumentPassing(t *testing.T) {
 			if tt.name == "20_int32" && (runtime.GOOS != "darwin" || runtime.GOARCH != "arm64") {
 				t.Skip("20 int32 arguments only supported on Darwin ARM64 with smart stack checking")
 			}
-			if tt.name == "10_float32" && (runtime.GOARCH == "loong64" || runtime.GOARCH == "riscv64") {
+			if tt.name == "10_float32" && (runtime.GOARCH == "loong64" || runtime.GOARCH == "ppc64le" || runtime.GOARCH == "riscv64") {
 				t.Skip("float32 stack arguments not yet supported on this platform")
 			}
 			// Struct tests require Darwin ARM64 or AMD64

internal/cgo/syscall_cgo_unix.go

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0
 // SPDX-FileCopyrightText: 2022 The Ebitengine Authors
 
-//go:build freebsd || (linux && !(386 || amd64 || arm || arm64 || loong64 || riscv64)) || netbsd
+//go:build freebsd || (linux && !(386 || amd64 || arm || arm64 || loong64 || ppc64le || riscv64)) || netbsd
 
 package cgo