Adding upstream version 1.20.14.upstream/1.20.14upstream

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

1 files changed, 107 insertions, 0 deletions

diff --git a/src/cmd/compile/internal/ssa/shift_test.go b/src/cmd/compile/internal/ssa/shift_test.go
new file mode 100644
index 0000000..06c2f67
--- /dev/null
+++ b/src/cmd/compile/internal/ssa/shift_test.go
@@ -0,0 +1,107 @@
+// Copyright 2015 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 ssa
+
+import (
+	"cmd/compile/internal/types"
+	"testing"
+)
+
+func TestShiftConstAMD64(t *testing.T) {
+	c := testConfig(t)
+	fun := makeConstShiftFunc(c, 18, OpLsh64x64, c.config.Types.UInt64)
+	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SHLQconst: 1, OpAMD64CMPQconst: 0, OpAMD64ANDQconst: 0})
+
+	fun = makeConstShiftFunc(c, 66, OpLsh64x64, c.config.Types.UInt64)
+	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SHLQconst: 0, OpAMD64CMPQconst: 0, OpAMD64ANDQconst: 0})
+
+	fun = makeConstShiftFunc(c, 18, OpRsh64Ux64, c.config.Types.UInt64)
+	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SHRQconst: 1, OpAMD64CMPQconst: 0, OpAMD64ANDQconst: 0})
+
+	fun = makeConstShiftFunc(c, 66, OpRsh64Ux64, c.config.Types.UInt64)
+	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SHRQconst: 0, OpAMD64CMPQconst: 0, OpAMD64ANDQconst: 0})
+
+	fun = makeConstShiftFunc(c, 18, OpRsh64x64, c.config.Types.Int64)
+	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SARQconst: 1, OpAMD64CMPQconst: 0})
+
+	fun = makeConstShiftFunc(c, 66, OpRsh64x64, c.config.Types.Int64)
+	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SARQconst: 1, OpAMD64CMPQconst: 0})
+}
+
+func makeConstShiftFunc(c *Conf, amount int64, op Op, typ *types.Type) fun {
+	ptyp := c.config.Types.BytePtr
+	fun := c.Fun("entry",
+		Bloc("entry",
+			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
+			Valu("SP", OpSP, c.config.Types.Uintptr, 0, nil),
+			Valu("argptr", OpOffPtr, ptyp, 8, nil, "SP"),
+			Valu("resptr", OpOffPtr, ptyp, 16, nil, "SP"),
+			Valu("load", OpLoad, typ, 0, nil, "argptr", "mem"),
+			Valu("c", OpConst64, c.config.Types.UInt64, amount, nil),
+			Valu("shift", op, typ, 0, nil, "load", "c"),
+			Valu("store", OpStore, types.TypeMem, 0, c.config.Types.UInt64, "resptr", "shift", "mem"),
+			Exit("store")))
+	Compile(fun.f)
+	return fun
+}
+
+func TestShiftToExtensionAMD64(t *testing.T) {
+	c := testConfig(t)
+	// Test that eligible pairs of constant shifts are converted to extensions.
+	// For example:
+	//   (uint64(x) << 32) >> 32 -> uint64(uint32(x))
+	ops := map[Op]int{
+		OpAMD64SHLQconst: 0, OpAMD64SHLLconst: 0,
+		OpAMD64SHRQconst: 0, OpAMD64SHRLconst: 0,
+		OpAMD64SARQconst: 0, OpAMD64SARLconst: 0,
+	}
+	tests := [...]struct {
+		amount      int64
+		left, right Op
+		typ         *types.Type
+	}{
+		// unsigned
+		{56, OpLsh64x64, OpRsh64Ux64, c.config.Types.UInt64},
+		{48, OpLsh64x64, OpRsh64Ux64, c.config.Types.UInt64},
+		{32, OpLsh64x64, OpRsh64Ux64, c.config.Types.UInt64},
+		{24, OpLsh32x64, OpRsh32Ux64, c.config.Types.UInt32},
+		{16, OpLsh32x64, OpRsh32Ux64, c.config.Types.UInt32},
+		{8, OpLsh16x64, OpRsh16Ux64, c.config.Types.UInt16},
+		// signed
+		{56, OpLsh64x64, OpRsh64x64, c.config.Types.Int64},
+		{48, OpLsh64x64, OpRsh64x64, c.config.Types.Int64},
+		{32, OpLsh64x64, OpRsh64x64, c.config.Types.Int64},
+		{24, OpLsh32x64, OpRsh32x64, c.config.Types.Int32},
+		{16, OpLsh32x64, OpRsh32x64, c.config.Types.Int32},
+		{8, OpLsh16x64, OpRsh16x64, c.config.Types.Int16},
+	}
+	for _, tc := range tests {
+		fun := makeShiftExtensionFunc(c, tc.amount, tc.left, tc.right, tc.typ)
+		checkOpcodeCounts(t, fun.f, ops)
+	}
+}
+
+// makeShiftExtensionFunc generates a function containing:
+//
+//	(rshift (lshift (Const64 [amount])) (Const64 [amount]))
+//
+// This may be equivalent to a sign or zero extension.
+func makeShiftExtensionFunc(c *Conf, amount int64, lshift, rshift Op, typ *types.Type) fun {
+	ptyp := c.config.Types.BytePtr
+	fun := c.Fun("entry",
+		Bloc("entry",
+			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
+			Valu("SP", OpSP, c.config.Types.Uintptr, 0, nil),
+			Valu("argptr", OpOffPtr, ptyp, 8, nil, "SP"),
+			Valu("resptr", OpOffPtr, ptyp, 16, nil, "SP"),
+			Valu("load", OpLoad, typ, 0, nil, "argptr", "mem"),
+			Valu("c", OpConst64, c.config.Types.UInt64, amount, nil),
+			Valu("lshift", lshift, typ, 0, nil, "load", "c"),
+			Valu("rshift", rshift, typ, 0, nil, "lshift", "c"),
+			Valu("store", OpStore, types.TypeMem, 0, c.config.Types.UInt64, "resptr", "rshift", "mem"),
+			Exit("store")))
+	Compile(fun.f)
+	return fun
+}