Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 298 insertions, 0 deletions

diff --git a/src/cmd/internal/sys/arch.go b/src/cmd/internal/sys/arch.go
new file mode 100644
index 0000000..2e35284
--- /dev/null
+++ b/src/cmd/internal/sys/arch.go
@@ -0,0 +1,285 @@
+// Copyright 2016 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.
+
+package sys
+
+import "encoding/binary"
+
+// ArchFamily represents a family of one or more related architectures.
+// For example, ppc64 and ppc64le are both members of the PPC64 family.
+type ArchFamily byte
+
+const (
+	NoArch ArchFamily = iota
+	AMD64
+	ARM
+	ARM64
+	I386
+	Loong64
+	MIPS
+	MIPS64
+	PPC64
+	RISCV64
+	S390X
+	Wasm
+)
+
+// Arch represents an individual architecture.
+type Arch struct {
+	Name   string
+	Family ArchFamily
+
+	ByteOrder binary.ByteOrder
+
+	// PtrSize is the size in bytes of pointers and the
+	// predeclared "int", "uint", and "uintptr" types.
+	PtrSize int
+
+	// RegSize is the size in bytes of general purpose registers.
+	RegSize int
+
+	// MinLC is the minimum length of an instruction code.
+	MinLC int
+
+	// Alignment is maximum alignment required by the architecture
+	// for any (compiler-generated) load or store instruction.
+	// Loads or stores smaller than Alignment must be naturally aligned.
+	// Loads or stores larger than Alignment need only be Alignment-aligned.
+	Alignment int8
+
+	// CanMergeLoads reports whether the backend optimization passes
+	// can combine adjacent loads into a single larger, possibly unaligned, load.
+	// Note that currently the optimizations must be able to handle little endian byte order.
+	CanMergeLoads bool
+
+	// CanJumpTable reports whether the backend can handle
+	// compiling a jump table.
+	CanJumpTable bool
+
+	// HasLR indicates that this architecture uses a link register
+	// for calls.
+	HasLR bool
+
+	// FixedFrameSize is the smallest possible offset from the
+	// hardware stack pointer to a local variable on the stack.
+	// Architectures that use a link register save its value on
+	// the stack in the function prologue and so always have a
+	// pointer between the hardware stack pointer and the local
+	// variable area.
+	FixedFrameSize int64
+}
+
+// InFamily reports whether a is a member of any of the specified
+// architecture families.
+func (a *Arch) InFamily(xs ...ArchFamily) bool {
+	for _, x := range xs {
+		if a.Family == x {
+			return true
+		}
+	}
+	return false
+}
+
+var Arch386 = &Arch{
+	Name:           "386",
+	Family:         I386,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        4,
+	RegSize:        4,
+	MinLC:          1,
+	Alignment:      1,
+	CanMergeLoads:  true,
+	HasLR:          false,
+	FixedFrameSize: 0,
+}
+
+var ArchAMD64 = &Arch{
+	Name:           "amd64",
+	Family:         AMD64,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          1,
+	Alignment:      1,
+	CanMergeLoads:  true,
+	CanJumpTable:   true,
+	HasLR:          false,
+	FixedFrameSize: 0,
+}
+
+var ArchARM = &Arch{
+	Name:           "arm",
+	Family:         ARM,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        4,
+	RegSize:        4,
+	MinLC:          4,
+	Alignment:      4, // TODO: just for arm5?
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 4, // LR
+}
+
+var ArchARM64 = &Arch{
+	Name:           "arm64",
+	Family:         ARM64,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          4,
+	Alignment:      1,
+	CanMergeLoads:  true,
+	CanJumpTable:   true,
+	HasLR:          true,
+	FixedFrameSize: 8, // LR
+}
+
+var ArchLoong64 = &Arch{
+	Name:           "loong64",
+	Family:         Loong64,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          4,
+	Alignment:      8, // Unaligned accesses are not guaranteed to be fast
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 8, // LR
+}
+
+var ArchMIPS = &Arch{
+	Name:           "mips",
+	Family:         MIPS,
+	ByteOrder:      binary.BigEndian,
+	PtrSize:        4,
+	RegSize:        4,
+	MinLC:          4,
+	Alignment:      4,
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 4, // LR
+}
+
+var ArchMIPSLE = &Arch{
+	Name:           "mipsle",
+	Family:         MIPS,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        4,
+	RegSize:        4,
+	MinLC:          4,
+	Alignment:      4,
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 4, // LR
+}
+
+var ArchMIPS64 = &Arch{
+	Name:           "mips64",
+	Family:         MIPS64,
+	ByteOrder:      binary.BigEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          4,
+	Alignment:      8,
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 8, // LR
+}
+
+var ArchMIPS64LE = &Arch{
+	Name:           "mips64le",
+	Family:         MIPS64,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          4,
+	Alignment:      8,
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 8, // LR
+}
+
+var ArchPPC64 = &Arch{
+	Name:          "ppc64",
+	Family:        PPC64,
+	ByteOrder:     binary.BigEndian,
+	PtrSize:       8,
+	RegSize:       8,
+	MinLC:         4,
+	Alignment:     1,
+	CanMergeLoads: false,
+	HasLR:         true,
+	// PIC code on ppc64le requires 32 bytes of stack, and it's
+	// easier to just use that much stack always.
+	FixedFrameSize: 4 * 8,
+}
+
+var ArchPPC64LE = &Arch{
+	Name:           "ppc64le",
+	Family:         PPC64,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          4,
+	Alignment:      1,
+	CanMergeLoads:  true,
+	HasLR:          true,
+	FixedFrameSize: 4 * 8,
+}
+
+var ArchRISCV64 = &Arch{
+	Name:           "riscv64",
+	Family:         RISCV64,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          4,
+	Alignment:      8, // riscv unaligned loads work, but are really slow (trap + simulated by OS)
+	CanMergeLoads:  false,
+	HasLR:          true,
+	FixedFrameSize: 8, // LR
+}
+
+var ArchS390X = &Arch{
+	Name:           "s390x",
+	Family:         S390X,
+	ByteOrder:      binary.BigEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          2,
+	Alignment:      1,
+	CanMergeLoads:  true,
+	HasLR:          true,
+	FixedFrameSize: 8, // LR
+}
+
+var ArchWasm = &Arch{
+	Name:           "wasm",
+	Family:         Wasm,
+	ByteOrder:      binary.LittleEndian,
+	PtrSize:        8,
+	RegSize:        8,
+	MinLC:          1,
+	Alignment:      1,
+	CanMergeLoads:  false,
+	HasLR:          false,
+	FixedFrameSize: 0,
+}
+
+var Archs = [...]*Arch{
+	Arch386,
+	ArchAMD64,
+	ArchARM,
+	ArchARM64,
+	ArchLoong64,
+	ArchMIPS,
+	ArchMIPSLE,
+	ArchMIPS64,
+	ArchMIPS64LE,
+	ArchPPC64,
+	ArchPPC64LE,
+	ArchRISCV64,
+	ArchS390X,
+	ArchWasm,
+}
diff --git a/src/cmd/internal/sys/args.go b/src/cmd/internal/sys/args.go
new file mode 100644
index 0000000..cc9fb64
--- /dev/null
+++ b/src/cmd/internal/sys/args.go
@@ -0,0 +1,13 @@
+// Copyright 2021 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.
+
+package sys
+
+// ExecArgLengthLimit is the number of bytes we can safely
+// pass as arguments to an exec.Command.
+//
+// Windows has a limit of 32 KB. To be conservative and not worry about whether
+// that includes spaces or not, just use 30 KB. Darwin's limit is less clear.
+// The OS claims 256KB, but we've seen failures with arglen as small as 50KB.
+const ExecArgLengthLimit = (30 << 10)