reserve 48 bytes in stack frame for ppc64

Author: zte-majiang

src/cmd/internal/obj/link.go

@@ -684,9 +684,13 @@ func (ctxt *Link) FixedFrameSize() int64 {
 	case sys.AMD64, sys.I386, sys.Wasm:
 		return 0
 	case sys.PPC64:
-		// PIC code on ppc64le requires 32 bytes of stack, and it's easier to
-		// just use that much stack always on ppc64x.
-		return int64(4 * ctxt.Arch.PtrSize)
+		// PIC code on ppc64le requires 32 bytes of stack.
+		// ppc64 requires 48 bytes at least.
+		if ctxt.Arch.Name == "ppc64le" {
+			return int64(4 * ctxt.Arch.PtrSize)
+		} else {
+			return int64(6 * ctxt.Arch.PtrSize)
+		}
 	default:
 		return int64(ctxt.Arch.PtrSize)
 	}

src/cmd/link/internal/ld/config.go

@@ -247,7 +247,8 @@ func determineLinkMode(ctxt *Link) {
 			}
 			ctxt.LinkMode = LinkInternal
 		case "1":
-			if objabi.GOARCH == "ppc64" && objabi.GOOS != "aix" {
+			// We have experimental support for linux/ppc64 now, see https://github.com/golang/go/issues/13192.
+			if objabi.GOARCH == "ppc64" && objabi.GOOS != "aix" && objabi.GOOS != "linux" {
 				Exitf("external linking requested via GO_EXTLINK_ENABLED but not supported for %s/ppc64", objabi.GOOS)
 			}
 			ctxt.LinkMode = LinkExternal
@@ -261,7 +262,7 @@ func determineLinkMode(ctxt *Link) {
 			} else {
 				ctxt.LinkMode = LinkInternal
 			}
-			if objabi.GOARCH == "ppc64" && objabi.GOOS != "aix" && ctxt.LinkMode == LinkExternal {
+			if objabi.GOARCH == "ppc64" && objabi.GOOS != "aix" && objabi.GOOS != "linux" && ctxt.LinkMode == LinkExternal {
 				Exitf("external linking is not supported for %s/ppc64", objabi.GOOS)
 			}
 		}
@@ -270,7 +271,7 @@ func determineLinkMode(ctxt *Link) {
 			Exitf("internal linking requested but external linking required: %s", reason)
 		}
 	case LinkExternal:
-		if objabi.GOARCH == "ppc64" && objabi.GOOS != "aix" {
+		if objabi.GOARCH == "ppc64" && objabi.GOOS != "aix" && objabi.GOOS != "linux" {
 			Exitf("external linking not supported for %s/ppc64", objabi.GOOS)
 		}
 	}

src/runtime/asm_ppc64x.h

@@ -20,6 +20,9 @@
 //
 // The reason for using a constant is to make supporting PIC easier (although
 // we only support PIC on ppc64le which has a minimum 32 bytes of stack frame,
-// and currently always use that much, PIC on ppc64 would need to use 48).
-
+// PIC on ppc64 would need to use 48).
+#ifdef GOARCH_ppc64le
 #define FIXED_FRAME 32
+#else
+#define FIXED_FRAME 48
+#endif

src/runtime/asm_ppc64x.s

@@ -13,7 +13,11 @@
 #ifdef GOOS_aix
 #define cgoCalleeStackSize 48
 #else
+#ifdef GOARCH_ppc64le
 #define cgoCalleeStackSize 32
+#else
+#define cgoCalleeStackSize 48
+#endif
 #endif
 
 TEXT runtime·rt0_go(SB),NOSPLIT,$0
@@ -94,6 +98,11 @@ nocgo:
 	MOVDU	R0, -8(R1)
 	MOVDU	R0, -8(R1)
 	MOVDU	R0, -8(R1)
+#ifdef GOARCH_ppc64
+	// ppc64 requires 48 bytes at least.
+	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
+#endif
 	BL	runtime·newproc(SB)
 	ADD	$(16+FIXED_FRAME), R1
 
@@ -199,6 +208,11 @@ TEXT runtime·mcall(SB), NOSPLIT|NOFRAME, $0-8
 	MOVDU	R0, -8(R1)
 	MOVDU	R0, -8(R1)
 	MOVDU	R0, -8(R1)
+#ifdef GOARCH_ppc64
+	// ppc64 requires 48 bytes at least.
+	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
+#endif
 	BL	(CTR)
 	MOVD	24(R1), R2
 	BR	runtime·badmcall2(SB)
@@ -565,7 +579,11 @@ TEXT gosave<>(SB),NOSPLIT|NOFRAME,$0
 #ifdef GOOS_aix
 #define asmcgocallSaveOffset cgoCalleeStackSize + 8
 #else
+#ifdef GOARCH_ppc64le
 #define asmcgocallSaveOffset cgoCalleeStackSize
+#else
+#define asmcgocallSaveOffset cgoCalleeStackSize + 8
+#endif
 #endif
 
 // func asmcgocall(fn, arg unsafe.Pointer) int32

src/runtime/internal/sys/arch_ppc64.go

@@ -11,7 +11,7 @@ const (
 	PCQuantum           = 4
 	Int64Align          = 8
 	HugePageSize        = 0
-	MinFrameSize        = 32
+	MinFrameSize        = 48
 )
 
 type Uintreg uint64

src/runtime/rt0_linux_ppc64.s

@@ -18,6 +18,7 @@ TEXT _main<>(SB),NOSPLIT,$-8
 	// There is no TLS base pointer.
 	//
 	// TODO(austin): Support ABI v1 dynamic linking entry point
+	XOR	R0, R0
 	MOVD	$runtime·rt0_go(SB), R12
 	MOVD	R12, CTR
 	MOVBZ	runtime·iscgo(SB), R5