Gecko [ 167.86.127.34 ]

Name	Size	Permission
gen	[ DIR ]	drwxr-xr-x
testdata	[ DIR ]	drwxr-xr-x
README.md	7.76 KB	-rw-r--r--
TODO	950 B	-rw-r--r--
biasedsparsemap.go	2.71 KB	-rw-r--r--
block.go	8.64 KB	-rw-r--r--
branchelim.go	11.41 KB	-rw-r--r--
branchelim_test.go	5.21 KB	-rw-r--r--
cache.go	2.46 KB	-rw-r--r--
check.go	13.9 KB	-rw-r--r--
checkbce.go	956 B	-rw-r--r--
compile.go	16.22 KB	-rw-r--r--
config.go	11.39 KB	-rw-r--r--
copyelim.go	1.82 KB	-rw-r--r--
copyelim_test.go	1.29 KB	-rw-r--r--
critical.go	3.15 KB	-rw-r--r--
cse.go	10.62 KB	-rw-r--r--
cse_test.go	4.21 KB	-rw-r--r--
deadcode.go	9.73 KB	-rw-r--r--
deadcode_test.go	3.49 KB	-rw-r--r--
deadstore.go	8.98 KB	-rw-r--r--
deadstore_test.go	4.09 KB	-rw-r--r--
debug.go	33.92 KB	-rw-r--r--
debug_test.go	28.68 KB	-rw-r--r--
decompose.go	10.91 KB	-rw-r--r--
dom.go	7.98 KB	-rw-r--r--
dom_test.go	13.34 KB	-rw-r--r--
export_test.go	5.68 KB	-rw-r--r--
flagalloc.go	5.49 KB	-rw-r--r--
func.go	22.17 KB	-rw-r--r--
func_test.go	12.85 KB	-rw-r--r--
fuse.go	5.7 KB	-rw-r--r--
fuse_test.go	5.04 KB	-rw-r--r--
html.go	29.04 KB	-rw-r--r--
id.go	576 B	-rw-r--r--
layout.go	3.56 KB	-rw-r--r--
lca.go	3.71 KB	-rw-r--r--
lca_test.go	1.65 KB	-rw-r--r--
likelyadjust.go	15.23 KB	-rw-r--r--
location.go	2.8 KB	-rw-r--r--
loopbce.go	9.85 KB	-rw-r--r--
loopreschedchecks.go	15.36 KB	-rw-r--r--
looprotate.go	2.24 KB	-rw-r--r--
lower.go	1.24 KB	-rw-r--r--
magic.go	13.42 KB	-rw-r--r--
magic_test.go	9.1 KB	-rw-r--r--
nilcheck.go	11.11 KB	-rw-r--r--
nilcheck_test.go	12.07 KB	-rw-r--r--
numberlines.go	8.44 KB	-rw-r--r--
op.go	8.74 KB	-rw-r--r--
opGen.go	839.32 KB	-rw-r--r--
opt.go	290 B	-rw-r--r--
passbm_test.go	3.14 KB	-rw-r--r--
phielim.go	1.47 KB	-rw-r--r--
phiopt.go	3.96 KB	-rw-r--r--
poset.go	37.23 KB	-rw-r--r--
poset_test.go	18.14 KB	-rw-r--r--
print.go	2.98 KB	-rw-r--r--
prove.go	36.68 KB	-rw-r--r--
redblack32.go	8.9 KB	-rw-r--r--
redblack32_test.go	5.96 KB	-rw-r--r--
regalloc.go	76.36 KB	-rw-r--r--
regalloc_test.go	6.41 KB	-rw-r--r--
rewrite.go	33.06 KB	-rw-r--r--
rewrite386.go	514.14 KB	-rw-r--r--
rewrite386splitload.go	3.7 KB	-rw-r--r--
rewriteAMD64.go	1.31 MB	-rw-r--r--
rewriteAMD64splitload.go	4.95 KB	-rw-r--r--
rewriteARM.go	538.26 KB	-rw-r--r--
rewriteARM64.go	837.68 KB	-rw-r--r--
rewriteMIPS.go	203.31 KB	-rw-r--r--
rewriteMIPS64.go	227.84 KB	-rw-r--r--
rewritePPC64.go	661.88 KB	-rw-r--r--
rewriteRISCV64.go	123.11 KB	-rw-r--r--
rewriteS390X.go	904.36 KB	-rw-r--r--
rewriteWasm.go	136.86 KB	-rw-r--r--
rewrite_test.go	3.01 KB	-rw-r--r--
rewritedec.go	10.56 KB	-rw-r--r--
rewritedec64.go	64.01 KB	-rw-r--r--
rewritedecArgs.go	6.6 KB	-rw-r--r--
rewritegeneric.go	1.09 MB	-rw-r--r--
schedule.go	13.99 KB	-rw-r--r--
schedule_test.go	2.91 KB	-rw-r--r--
shift_test.go	4.05 KB	-rw-r--r--
shortcircuit.go	3.97 KB	-rw-r--r--
shortcircuit_test.go	1.31 KB	-rw-r--r--
sizeof_test.go	855 B	-rw-r--r--
softfloat.go	1.94 KB	-rw-r--r--
sparsemap.go	1.98 KB	-rw-r--r--
sparseset.go	1.54 KB	-rw-r--r--
sparsetree.go	7.88 KB	-rw-r--r--
sparsetreemap.go	7.67 KB	-rw-r--r--
stackalloc.go	10.95 KB	-rw-r--r--
stackframe.go	290 B	-rw-r--r--
stmtlines_test.go	2.75 KB	-rw-r--r--
tighten.go	4.21 KB	-rw-r--r--
trim.go	4.24 KB	-rw-r--r--
value.go	10.71 KB	-rw-r--r--
writebarrier.go	17.92 KB	-rw-r--r--
writebarrier_test.go	1.75 KB	-rw-r--r--
xposmap.go	3.29 KB	-rw-r--r--
zcse.go	2.12 KB	-rw-r--r--
zeroextension_test.go	1.66 KB	-rw-r--r--

Code Editor : nilcheck_test.go

package ssa

import (
	"cmd/compile/internal/types"
	"strconv"
	"testing"
)

func BenchmarkNilCheckDeep1(b *testing.B)     { benchmarkNilCheckDeep(b, 1) }
func BenchmarkNilCheckDeep10(b *testing.B)    { benchmarkNilCheckDeep(b, 10) }
func BenchmarkNilCheckDeep100(b *testing.B)   { benchmarkNilCheckDeep(b, 100) }
func BenchmarkNilCheckDeep1000(b *testing.B)  { benchmarkNilCheckDeep(b, 1000) }
func BenchmarkNilCheckDeep10000(b *testing.B) { benchmarkNilCheckDeep(b, 10000) }

// benchmarkNilCheckDeep is a stress test of nilcheckelim.
// It uses the worst possible input: A linear string of
// nil checks, none of which can be eliminated.
// Run with multiple depths to observe big-O behavior.
func benchmarkNilCheckDeep(b *testing.B, depth int) {
	c := testConfig(b)
	ptrType := c.config.Types.BytePtr

var blocs []bloc
	blocs = append(blocs,
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto(blockn(0)),
		),
	)
	for i := 0; i < depth; i++ {
		blocs = append(blocs,
			Bloc(blockn(i),
				Valu(ptrn(i), OpAddr, ptrType, 0, nil, "sb"),
				Valu(booln(i), OpIsNonNil, c.config.Types.Bool, 0, nil, ptrn(i)),
				If(booln(i), blockn(i+1), "exit"),
			),
		)
	}
	blocs = append(blocs,
		Bloc(blockn(depth), Goto("exit")),
		Bloc("exit", Exit("mem")),
	)

fun := c.Fun("entry", blocs...)

CheckFunc(fun.f)
	b.SetBytes(int64(depth)) // helps for eyeballing linearity
	b.ResetTimer()
	b.ReportAllocs()

for i := 0; i < b.N; i++ {
		nilcheckelim(fun.f)
	}
}

func blockn(n int) string { return "b" + strconv.Itoa(n) }
func ptrn(n int) string   { return "p" + strconv.Itoa(n) }
func booln(n int) string  { return "c" + strconv.Itoa(n) }

func isNilCheck(b *Block) bool {
	return b.Kind == BlockIf && b.Controls[0].Op == OpIsNonNil
}

// TestNilcheckSimple verifies that a second repeated nilcheck is removed.
func TestNilcheckSimple(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("bool1", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool1", "secondCheck", "exit")),
		Bloc("secondCheck",
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool2", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["secondCheck"] && isNilCheck(b) {
			t.Errorf("secondCheck was not eliminated")
		}
	}
}

// TestNilcheckDomOrder ensures that the nil check elimination isn't dependent
// on the order of the dominees.
func TestNilcheckDomOrder(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("bool1", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool1", "secondCheck", "exit")),
		Bloc("exit",
			Exit("mem")),
		Bloc("secondCheck",
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool2", "extra", "exit")),
		Bloc("extra",
			Goto("exit")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["secondCheck"] && isNilCheck(b) {
			t.Errorf("secondCheck was not eliminated")
		}
	}
}

// TestNilcheckAddr verifies that nilchecks of OpAddr constructed values are removed.
func TestNilcheckAddr(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpAddr, ptrType, 0, nil, "sb"),
			Valu("bool1", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool1", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["checkPtr"] && isNilCheck(b) {
			t.Errorf("checkPtr was not eliminated")
		}
	}
}

// TestNilcheckAddPtr verifies that nilchecks of OpAddPtr constructed values are removed.
func TestNilcheckAddPtr(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("off", OpConst64, c.config.Types.Int64, 20, nil),
			Valu("ptr1", OpAddPtr, ptrType, 0, nil, "sb", "off"),
			Valu("bool1", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool1", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["checkPtr"] && isNilCheck(b) {
			t.Errorf("checkPtr was not eliminated")
		}
	}
}

// TestNilcheckPhi tests that nil checks of phis, for which all values are known to be
// non-nil are removed.
func TestNilcheckPhi(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Valu("sp", OpSP, c.config.Types.Uintptr, 0, nil),
			Valu("baddr", OpLocalAddr, c.config.Types.Bool, 0, "b", "sp", "mem"),
			Valu("bool1", OpLoad, c.config.Types.Bool, 0, nil, "baddr", "mem"),
			If("bool1", "b1", "b2")),
		Bloc("b1",
			Valu("ptr1", OpAddr, ptrType, 0, nil, "sb"),
			Goto("checkPtr")),
		Bloc("b2",
			Valu("ptr2", OpAddr, ptrType, 0, nil, "sb"),
			Goto("checkPtr")),
		// both ptr1 and ptr2 are guaranteed non-nil here
		Bloc("checkPtr",
			Valu("phi", OpPhi, ptrType, 0, nil, "ptr1", "ptr2"),
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "phi"),
			If("bool2", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["checkPtr"] && isNilCheck(b) {
			t.Errorf("checkPtr was not eliminated")
		}
	}
}

// TestNilcheckKeepRemove verifies that duplicate checks of the same pointer
// are removed, but checks of different pointers are not.
func TestNilcheckKeepRemove(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("bool1", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool1", "differentCheck", "exit")),
		Bloc("differentCheck",
			Valu("ptr2", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr2"),
			If("bool2", "secondCheck", "exit")),
		Bloc("secondCheck",
			Valu("bool3", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool3", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	foundDifferentCheck := false
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["secondCheck"] && isNilCheck(b) {
			t.Errorf("secondCheck was not eliminated")
		}
		if b == fun.blocks["differentCheck"] && isNilCheck(b) {
			foundDifferentCheck = true
		}
	}
	if !foundDifferentCheck {
		t.Errorf("removed differentCheck, but shouldn't have")
	}
}

// TestNilcheckInFalseBranch tests that nil checks in the false branch of a nilcheck
// block are *not* removed.
func TestNilcheckInFalseBranch(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("bool1", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool1", "extra", "secondCheck")),
		Bloc("secondCheck",
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool2", "extra", "thirdCheck")),
		Bloc("thirdCheck",
			Valu("bool3", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool3", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	foundSecondCheck := false
	foundThirdCheck := false
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["secondCheck"] && isNilCheck(b) {
			foundSecondCheck = true
		}
		if b == fun.blocks["thirdCheck"] && isNilCheck(b) {
			foundThirdCheck = true
		}
	}
	if !foundSecondCheck {
		t.Errorf("removed secondCheck, but shouldn't have [false branch]")
	}
	if !foundThirdCheck {
		t.Errorf("removed thirdCheck, but shouldn't have [false branch]")
	}
}

// TestNilcheckUser verifies that a user nil check that dominates a generated nil check
// wil remove the generated nil check.
func TestNilcheckUser(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("nilptr", OpConstNil, ptrType, 0, nil),
			Valu("bool1", OpNeqPtr, c.config.Types.Bool, 0, nil, "ptr1", "nilptr"),
			If("bool1", "secondCheck", "exit")),
		Bloc("secondCheck",
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool2", "extra", "exit")),
		Bloc("extra",
			Goto("exit")),
		Bloc("exit",
			Exit("mem")))

CheckFunc(fun.f)
	// we need the opt here to rewrite the user nilcheck
	opt(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["secondCheck"] && isNilCheck(b) {
			t.Errorf("secondCheck was not eliminated")
		}
	}
}

// TestNilcheckBug reproduces a bug in nilcheckelim found by compiling math/big
func TestNilcheckBug(t *testing.T) {
	c := testConfig(t)
	ptrType := c.config.Types.BytePtr
	fun := c.Fun("entry",
		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("sb", OpSB, c.config.Types.Uintptr, 0, nil),
			Goto("checkPtr")),
		Bloc("checkPtr",
			Valu("ptr1", OpLoad, ptrType, 0, nil, "sb", "mem"),
			Valu("nilptr", OpConstNil, ptrType, 0, nil),
			Valu("bool1", OpNeqPtr, c.config.Types.Bool, 0, nil, "ptr1", "nilptr"),
			If("bool1", "secondCheck", "couldBeNil")),
		Bloc("couldBeNil",
			Goto("secondCheck")),
		Bloc("secondCheck",
			Valu("bool2", OpIsNonNil, c.config.Types.Bool, 0, nil, "ptr1"),
			If("bool2", "extra", "exit")),
		Bloc("extra",
			// prevent fuse from eliminating this block
			Valu("store", OpStore, types.TypeMem, 0, ptrType, "ptr1", "nilptr", "mem"),
			Goto("exit")),
		Bloc("exit",
			Valu("phi", OpPhi, types.TypeMem, 0, nil, "mem", "store"),
			Exit("phi")))

CheckFunc(fun.f)
	// we need the opt here to rewrite the user nilcheck
	opt(fun.f)
	nilcheckelim(fun.f)

// clean up the removed nil check
	fusePlain(fun.f)
	deadcode(fun.f)

CheckFunc(fun.f)
	foundSecondCheck := false
	for _, b := range fun.f.Blocks {
		if b == fun.blocks["secondCheck"] && isNilCheck(b) {
			foundSecondCheck = true
		}
	}
	if !foundSecondCheck {
		t.Errorf("secondCheck was eliminated, but shouldn't have")
	}
}

${this.title}

Code Editor : nilcheck_test.go