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-rw-r--r--src/cmd/compile/internal/ssa/check.go597
1 files changed, 597 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/ssa/check.go b/src/cmd/compile/internal/ssa/check.go
new file mode 100644
index 0000000..2dade7a
--- /dev/null
+++ b/src/cmd/compile/internal/ssa/check.go
@@ -0,0 +1,597 @@
+// 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/internal/obj/s390x"
+ "math"
+ "math/bits"
+)
+
+// checkFunc checks invariants of f.
+func checkFunc(f *Func) {
+ blockMark := make([]bool, f.NumBlocks())
+ valueMark := make([]bool, f.NumValues())
+
+ for _, b := range f.Blocks {
+ if blockMark[b.ID] {
+ f.Fatalf("block %s appears twice in %s!", b, f.Name)
+ }
+ blockMark[b.ID] = true
+ if b.Func != f {
+ f.Fatalf("%s.Func=%s, want %s", b, b.Func.Name, f.Name)
+ }
+
+ for i, e := range b.Preds {
+ if se := e.b.Succs[e.i]; se.b != b || se.i != i {
+ f.Fatalf("block pred/succ not crosslinked correctly %d:%s %d:%s", i, b, se.i, se.b)
+ }
+ }
+ for i, e := range b.Succs {
+ if pe := e.b.Preds[e.i]; pe.b != b || pe.i != i {
+ f.Fatalf("block succ/pred not crosslinked correctly %d:%s %d:%s", i, b, pe.i, pe.b)
+ }
+ }
+
+ switch b.Kind {
+ case BlockExit:
+ if len(b.Succs) != 0 {
+ f.Fatalf("exit block %s has successors", b)
+ }
+ if b.NumControls() != 1 {
+ f.Fatalf("exit block %s has no control value", b)
+ }
+ if !b.Controls[0].Type.IsMemory() {
+ f.Fatalf("exit block %s has non-memory control value %s", b, b.Controls[0].LongString())
+ }
+ case BlockRet:
+ if len(b.Succs) != 0 {
+ f.Fatalf("ret block %s has successors", b)
+ }
+ if b.NumControls() != 1 {
+ f.Fatalf("ret block %s has nil control", b)
+ }
+ if !b.Controls[0].Type.IsMemory() {
+ f.Fatalf("ret block %s has non-memory control value %s", b, b.Controls[0].LongString())
+ }
+ case BlockRetJmp:
+ if len(b.Succs) != 0 {
+ f.Fatalf("retjmp block %s len(Succs)==%d, want 0", b, len(b.Succs))
+ }
+ if b.NumControls() != 1 {
+ f.Fatalf("retjmp block %s has nil control", b)
+ }
+ if !b.Controls[0].Type.IsMemory() {
+ f.Fatalf("retjmp block %s has non-memory control value %s", b, b.Controls[0].LongString())
+ }
+ if b.Aux == nil {
+ f.Fatalf("retjmp block %s has nil Aux field", b)
+ }
+ case BlockPlain:
+ if len(b.Succs) != 1 {
+ f.Fatalf("plain block %s len(Succs)==%d, want 1", b, len(b.Succs))
+ }
+ if b.NumControls() != 0 {
+ f.Fatalf("plain block %s has non-nil control %s", b, b.Controls[0].LongString())
+ }
+ case BlockIf:
+ if len(b.Succs) != 2 {
+ f.Fatalf("if block %s len(Succs)==%d, want 2", b, len(b.Succs))
+ }
+ if b.NumControls() != 1 {
+ f.Fatalf("if block %s has no control value", b)
+ }
+ if !b.Controls[0].Type.IsBoolean() {
+ f.Fatalf("if block %s has non-bool control value %s", b, b.Controls[0].LongString())
+ }
+ case BlockDefer:
+ if len(b.Succs) != 2 {
+ f.Fatalf("defer block %s len(Succs)==%d, want 2", b, len(b.Succs))
+ }
+ if b.NumControls() != 1 {
+ f.Fatalf("defer block %s has no control value", b)
+ }
+ if !b.Controls[0].Type.IsMemory() {
+ f.Fatalf("defer block %s has non-memory control value %s", b, b.Controls[0].LongString())
+ }
+ case BlockFirst:
+ if len(b.Succs) != 2 {
+ f.Fatalf("plain/dead block %s len(Succs)==%d, want 2", b, len(b.Succs))
+ }
+ if b.NumControls() != 0 {
+ f.Fatalf("plain/dead block %s has a control value", b)
+ }
+ }
+ if len(b.Succs) != 2 && b.Likely != BranchUnknown {
+ f.Fatalf("likeliness prediction %d for block %s with %d successors", b.Likely, b, len(b.Succs))
+ }
+
+ for _, v := range b.Values {
+ // Check to make sure argument count makes sense (argLen of -1 indicates
+ // variable length args)
+ nArgs := opcodeTable[v.Op].argLen
+ if nArgs != -1 && int32(len(v.Args)) != nArgs {
+ f.Fatalf("value %s has %d args, expected %d", v.LongString(),
+ len(v.Args), nArgs)
+ }
+
+ // Check to make sure aux values make sense.
+ canHaveAux := false
+ canHaveAuxInt := false
+ // TODO: enforce types of Aux in this switch (like auxString does below)
+ switch opcodeTable[v.Op].auxType {
+ case auxNone:
+ case auxBool:
+ if v.AuxInt < 0 || v.AuxInt > 1 {
+ f.Fatalf("bad bool AuxInt value for %v", v)
+ }
+ canHaveAuxInt = true
+ case auxInt8:
+ if v.AuxInt != int64(int8(v.AuxInt)) {
+ f.Fatalf("bad int8 AuxInt value for %v", v)
+ }
+ canHaveAuxInt = true
+ case auxInt16:
+ if v.AuxInt != int64(int16(v.AuxInt)) {
+ f.Fatalf("bad int16 AuxInt value for %v", v)
+ }
+ canHaveAuxInt = true
+ case auxInt32:
+ if v.AuxInt != int64(int32(v.AuxInt)) {
+ f.Fatalf("bad int32 AuxInt value for %v", v)
+ }
+ canHaveAuxInt = true
+ case auxInt64, auxARM64BitField:
+ canHaveAuxInt = true
+ case auxInt128:
+ // AuxInt must be zero, so leave canHaveAuxInt set to false.
+ case auxUInt8:
+ if v.AuxInt != int64(uint8(v.AuxInt)) {
+ f.Fatalf("bad uint8 AuxInt value for %v", v)
+ }
+ canHaveAuxInt = true
+ case auxFloat32:
+ canHaveAuxInt = true
+ if math.IsNaN(v.AuxFloat()) {
+ f.Fatalf("value %v has an AuxInt that encodes a NaN", v)
+ }
+ if !isExactFloat32(v.AuxFloat()) {
+ f.Fatalf("value %v has an AuxInt value that is not an exact float32", v)
+ }
+ case auxFloat64:
+ canHaveAuxInt = true
+ if math.IsNaN(v.AuxFloat()) {
+ f.Fatalf("value %v has an AuxInt that encodes a NaN", v)
+ }
+ case auxString:
+ if _, ok := v.Aux.(string); !ok {
+ f.Fatalf("value %v has Aux type %T, want string", v, v.Aux)
+ }
+ canHaveAux = true
+ case auxCallOff:
+ canHaveAuxInt = true
+ fallthrough
+ case auxCall:
+ if ac, ok := v.Aux.(*AuxCall); ok {
+ if v.Op == OpStaticCall && ac.Fn == nil {
+ f.Fatalf("value %v has *AuxCall with nil Fn", v)
+ }
+ } else {
+ f.Fatalf("value %v has Aux type %T, want *AuxCall", v, v.Aux)
+ }
+ canHaveAux = true
+ case auxSym, auxTyp:
+ canHaveAux = true
+ case auxSymOff, auxSymValAndOff, auxTypSize:
+ canHaveAuxInt = true
+ canHaveAux = true
+ case auxCCop:
+ if opcodeTable[Op(v.AuxInt)].name == "OpInvalid" {
+ f.Fatalf("value %v has an AuxInt value that is a valid opcode", v)
+ }
+ canHaveAuxInt = true
+ case auxS390XCCMask:
+ if _, ok := v.Aux.(s390x.CCMask); !ok {
+ f.Fatalf("bad type %T for S390XCCMask in %v", v.Aux, v)
+ }
+ canHaveAux = true
+ case auxS390XRotateParams:
+ if _, ok := v.Aux.(s390x.RotateParams); !ok {
+ f.Fatalf("bad type %T for S390XRotateParams in %v", v.Aux, v)
+ }
+ canHaveAux = true
+ case auxFlagConstant:
+ if v.AuxInt < 0 || v.AuxInt > 15 {
+ f.Fatalf("bad FlagConstant AuxInt value for %v", v)
+ }
+ canHaveAuxInt = true
+ default:
+ f.Fatalf("unknown aux type for %s", v.Op)
+ }
+ if !canHaveAux && v.Aux != nil {
+ f.Fatalf("value %s has an Aux value %v but shouldn't", v.LongString(), v.Aux)
+ }
+ if !canHaveAuxInt && v.AuxInt != 0 {
+ f.Fatalf("value %s has an AuxInt value %d but shouldn't", v.LongString(), v.AuxInt)
+ }
+
+ for i, arg := range v.Args {
+ if arg == nil {
+ f.Fatalf("value %s has nil arg", v.LongString())
+ }
+ if v.Op != OpPhi {
+ // For non-Phi ops, memory args must be last, if present
+ if arg.Type.IsMemory() && i != len(v.Args)-1 {
+ f.Fatalf("value %s has non-final memory arg (%d < %d)", v.LongString(), i, len(v.Args)-1)
+ }
+ }
+ }
+
+ if valueMark[v.ID] {
+ f.Fatalf("value %s appears twice!", v.LongString())
+ }
+ valueMark[v.ID] = true
+
+ if v.Block != b {
+ f.Fatalf("%s.block != %s", v, b)
+ }
+ if v.Op == OpPhi && len(v.Args) != len(b.Preds) {
+ f.Fatalf("phi length %s does not match pred length %d for block %s", v.LongString(), len(b.Preds), b)
+ }
+
+ if v.Op == OpAddr {
+ if len(v.Args) == 0 {
+ f.Fatalf("no args for OpAddr %s", v.LongString())
+ }
+ if v.Args[0].Op != OpSB {
+ f.Fatalf("bad arg to OpAddr %v", v)
+ }
+ }
+
+ if v.Op == OpLocalAddr {
+ if len(v.Args) != 2 {
+ f.Fatalf("wrong # of args for OpLocalAddr %s", v.LongString())
+ }
+ if v.Args[0].Op != OpSP {
+ f.Fatalf("bad arg 0 to OpLocalAddr %v", v)
+ }
+ if !v.Args[1].Type.IsMemory() {
+ f.Fatalf("bad arg 1 to OpLocalAddr %v", v)
+ }
+ }
+
+ if f.RegAlloc != nil && f.Config.SoftFloat && v.Type.IsFloat() {
+ f.Fatalf("unexpected floating-point type %v", v.LongString())
+ }
+
+ // Check types.
+ // TODO: more type checks?
+ switch c := f.Config; v.Op {
+ case OpSP, OpSB:
+ if v.Type != c.Types.Uintptr {
+ f.Fatalf("bad %s type: want uintptr, have %s",
+ v.Op, v.Type.String())
+ }
+ case OpStringLen:
+ if v.Type != c.Types.Int {
+ f.Fatalf("bad %s type: want int, have %s",
+ v.Op, v.Type.String())
+ }
+ case OpLoad:
+ if !v.Args[1].Type.IsMemory() {
+ f.Fatalf("bad arg 1 type to %s: want mem, have %s",
+ v.Op, v.Args[1].Type.String())
+ }
+ case OpStore:
+ if !v.Type.IsMemory() {
+ f.Fatalf("bad %s type: want mem, have %s",
+ v.Op, v.Type.String())
+ }
+ if !v.Args[2].Type.IsMemory() {
+ f.Fatalf("bad arg 2 type to %s: want mem, have %s",
+ v.Op, v.Args[2].Type.String())
+ }
+ case OpCondSelect:
+ if !v.Args[2].Type.IsBoolean() {
+ f.Fatalf("bad arg 2 type to %s: want boolean, have %s",
+ v.Op, v.Args[2].Type.String())
+ }
+ case OpAddPtr:
+ if !v.Args[0].Type.IsPtrShaped() && v.Args[0].Type != c.Types.Uintptr {
+ f.Fatalf("bad arg 0 type to %s: want ptr, have %s", v.Op, v.Args[0].LongString())
+ }
+ if !v.Args[1].Type.IsInteger() {
+ f.Fatalf("bad arg 1 type to %s: want integer, have %s", v.Op, v.Args[1].LongString())
+ }
+
+ }
+
+ // TODO: check for cycles in values
+ }
+ }
+
+ // Check to make sure all Blocks referenced are in the function.
+ if !blockMark[f.Entry.ID] {
+ f.Fatalf("entry block %v is missing", f.Entry)
+ }
+ for _, b := range f.Blocks {
+ for _, c := range b.Preds {
+ if !blockMark[c.b.ID] {
+ f.Fatalf("predecessor block %v for %v is missing", c, b)
+ }
+ }
+ for _, c := range b.Succs {
+ if !blockMark[c.b.ID] {
+ f.Fatalf("successor block %v for %v is missing", c, b)
+ }
+ }
+ }
+
+ if len(f.Entry.Preds) > 0 {
+ f.Fatalf("entry block %s of %s has predecessor(s) %v", f.Entry, f.Name, f.Entry.Preds)
+ }
+
+ // Check to make sure all Values referenced are in the function.
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ for i, a := range v.Args {
+ if !valueMark[a.ID] {
+ f.Fatalf("%v, arg %d of %s, is missing", a, i, v.LongString())
+ }
+ }
+ }
+ for _, c := range b.ControlValues() {
+ if !valueMark[c.ID] {
+ f.Fatalf("control value for %s is missing: %v", b, c)
+ }
+ }
+ }
+ for b := f.freeBlocks; b != nil; b = b.succstorage[0].b {
+ if blockMark[b.ID] {
+ f.Fatalf("used block b%d in free list", b.ID)
+ }
+ }
+ for v := f.freeValues; v != nil; v = v.argstorage[0] {
+ if valueMark[v.ID] {
+ f.Fatalf("used value v%d in free list", v.ID)
+ }
+ }
+
+ // Check to make sure all args dominate uses.
+ if f.RegAlloc == nil {
+ // Note: regalloc introduces non-dominating args.
+ // See TODO in regalloc.go.
+ sdom := f.Sdom()
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ for i, arg := range v.Args {
+ x := arg.Block
+ y := b
+ if v.Op == OpPhi {
+ y = b.Preds[i].b
+ }
+ if !domCheck(f, sdom, x, y) {
+ f.Fatalf("arg %d of value %s does not dominate, arg=%s", i, v.LongString(), arg.LongString())
+ }
+ }
+ }
+ for _, c := range b.ControlValues() {
+ if !domCheck(f, sdom, c.Block, b) {
+ f.Fatalf("control value %s for %s doesn't dominate", c, b)
+ }
+ }
+ }
+ }
+
+ // Check loop construction
+ if f.RegAlloc == nil && f.pass != nil { // non-nil pass allows better-targeted debug printing
+ ln := f.loopnest()
+ if !ln.hasIrreducible {
+ po := f.postorder() // use po to avoid unreachable blocks.
+ for _, b := range po {
+ for _, s := range b.Succs {
+ bb := s.Block()
+ if ln.b2l[b.ID] == nil && ln.b2l[bb.ID] != nil && bb != ln.b2l[bb.ID].header {
+ f.Fatalf("block %s not in loop branches to non-header block %s in loop", b.String(), bb.String())
+ }
+ if ln.b2l[b.ID] != nil && ln.b2l[bb.ID] != nil && bb != ln.b2l[bb.ID].header && !ln.b2l[b.ID].isWithinOrEq(ln.b2l[bb.ID]) {
+ f.Fatalf("block %s in loop branches to non-header block %s in non-containing loop", b.String(), bb.String())
+ }
+ }
+ }
+ }
+ }
+
+ // Check use counts
+ uses := make([]int32, f.NumValues())
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ for _, a := range v.Args {
+ uses[a.ID]++
+ }
+ }
+ for _, c := range b.ControlValues() {
+ uses[c.ID]++
+ }
+ }
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ if v.Uses != uses[v.ID] {
+ f.Fatalf("%s has %d uses, but has Uses=%d", v, uses[v.ID], v.Uses)
+ }
+ }
+ }
+
+ memCheck(f)
+}
+
+func memCheck(f *Func) {
+ // Check that if a tuple has a memory type, it is second.
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ if v.Type.IsTuple() && v.Type.FieldType(0).IsMemory() {
+ f.Fatalf("memory is first in a tuple: %s\n", v.LongString())
+ }
+ }
+ }
+
+ // Single live memory checks.
+ // These checks only work if there are no memory copies.
+ // (Memory copies introduce ambiguity about which mem value is really live.
+ // probably fixable, but it's easier to avoid the problem.)
+ // For the same reason, disable this check if some memory ops are unused.
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ if (v.Op == OpCopy || v.Uses == 0) && v.Type.IsMemory() {
+ return
+ }
+ }
+ if b != f.Entry && len(b.Preds) == 0 {
+ return
+ }
+ }
+
+ // Compute live memory at the end of each block.
+ lastmem := make([]*Value, f.NumBlocks())
+ ss := newSparseSet(f.NumValues())
+ for _, b := range f.Blocks {
+ // Mark overwritten memory values. Those are args of other
+ // ops that generate memory values.
+ ss.clear()
+ for _, v := range b.Values {
+ if v.Op == OpPhi || !v.Type.IsMemory() {
+ continue
+ }
+ if m := v.MemoryArg(); m != nil {
+ ss.add(m.ID)
+ }
+ }
+ // There should be at most one remaining unoverwritten memory value.
+ for _, v := range b.Values {
+ if !v.Type.IsMemory() {
+ continue
+ }
+ if ss.contains(v.ID) {
+ continue
+ }
+ if lastmem[b.ID] != nil {
+ f.Fatalf("two live memory values in %s: %s and %s", b, lastmem[b.ID], v)
+ }
+ lastmem[b.ID] = v
+ }
+ // If there is no remaining memory value, that means there was no memory update.
+ // Take any memory arg.
+ if lastmem[b.ID] == nil {
+ for _, v := range b.Values {
+ if v.Op == OpPhi {
+ continue
+ }
+ m := v.MemoryArg()
+ if m == nil {
+ continue
+ }
+ if lastmem[b.ID] != nil && lastmem[b.ID] != m {
+ f.Fatalf("two live memory values in %s: %s and %s", b, lastmem[b.ID], m)
+ }
+ lastmem[b.ID] = m
+ }
+ }
+ }
+ // Propagate last live memory through storeless blocks.
+ for {
+ changed := false
+ for _, b := range f.Blocks {
+ if lastmem[b.ID] != nil {
+ continue
+ }
+ for _, e := range b.Preds {
+ p := e.b
+ if lastmem[p.ID] != nil {
+ lastmem[b.ID] = lastmem[p.ID]
+ changed = true
+ break
+ }
+ }
+ }
+ if !changed {
+ break
+ }
+ }
+ // Check merge points.
+ for _, b := range f.Blocks {
+ for _, v := range b.Values {
+ if v.Op == OpPhi && v.Type.IsMemory() {
+ for i, a := range v.Args {
+ if a != lastmem[b.Preds[i].b.ID] {
+ f.Fatalf("inconsistent memory phi %s %d %s %s", v.LongString(), i, a, lastmem[b.Preds[i].b.ID])
+ }
+ }
+ }
+ }
+ }
+
+ // Check that only one memory is live at any point.
+ if f.scheduled {
+ for _, b := range f.Blocks {
+ var mem *Value // the current live memory in the block
+ for _, v := range b.Values {
+ if v.Op == OpPhi {
+ if v.Type.IsMemory() {
+ mem = v
+ }
+ continue
+ }
+ if mem == nil && len(b.Preds) > 0 {
+ // If no mem phi, take mem of any predecessor.
+ mem = lastmem[b.Preds[0].b.ID]
+ }
+ for _, a := range v.Args {
+ if a.Type.IsMemory() && a != mem {
+ f.Fatalf("two live mems @ %s: %s and %s", v, mem, a)
+ }
+ }
+ if v.Type.IsMemory() {
+ mem = v
+ }
+ }
+ }
+ }
+
+ // Check that after scheduling, phis are always first in the block.
+ if f.scheduled {
+ for _, b := range f.Blocks {
+ seenNonPhi := false
+ for _, v := range b.Values {
+ switch v.Op {
+ case OpPhi:
+ if seenNonPhi {
+ f.Fatalf("phi after non-phi @ %s: %s", b, v)
+ }
+ default:
+ seenNonPhi = true
+ }
+ }
+ }
+ }
+}
+
+// domCheck reports whether x dominates y (including x==y).
+func domCheck(f *Func, sdom SparseTree, x, y *Block) bool {
+ if !sdom.IsAncestorEq(f.Entry, y) {
+ // unreachable - ignore
+ return true
+ }
+ return sdom.IsAncestorEq(x, y)
+}
+
+// isExactFloat32 reports whether x can be exactly represented as a float32.
+func isExactFloat32(x float64) bool {
+ // Check the mantissa is in range.
+ if bits.TrailingZeros64(math.Float64bits(x)) < 52-23 {
+ return false
+ }
+ // Check the exponent is in range. The mantissa check above is sufficient for NaN values.
+ return math.IsNaN(x) || x == float64(float32(x))
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 18:08:58 +0000