[dev.fuzz] all: merge master (af72ddf) into dev.fuzz

This now includes the fix in CL 350729, which means
we no longer need to skip the test in dev.fuzz.

Conflicts:

- src/cmd/compile/internal/noder/unified_test.go

Merge List:

+ 2021-09-20 af72ddfcd7 cmd/compile: extend dump-to-file to handle "genssa" (asm) case.
+ 2021-09-20 3c764babe7 cmd/go: write go.mod requirements more consistently for go 1.17+
+ 2021-09-20 6268468e02 cmd/link: generate DIE for types referenced only through dictionaries
+ 2021-09-20 6acac8b685 cmd/compile: delay all transforms for generic funcs/methods
+ 2021-09-20 988f18d61d go/types: export Named._Orig as Named.Origin
+ 2021-09-20 b6dddaccd7 cmd/compile: fix transform.AssignOp to deal with tricky case
+ 2021-09-20 9e60c37147 cmd/compile: document register-based ABI for ppc64
+ 2021-09-20 79159f2e83 cmd/compile: fix simplification rules on arm/arm64
+ 2021-09-20 eff27e858b cmd/compile: ensure constant shift amounts are in range for arm
+ 2021-09-20 9ebe7c8ec6 go/test: add a test for issue 48344
+ 2021-09-20 6f35430faa cmd/compile: allow rotates to be merged with logical ops on arm64
+ 2021-09-20 2d9b486420 cmd/compile: update doc at top of iexport.go on the changes for typeparams
+ 2021-09-20 a81b0dc6ee cmd/compile: rename instType -> instanceType
+ 2021-09-20 119213566a cmd/cgo: remove hardcoded '-pie' ldflag for linux/arm
+ 2021-09-20 a83a558733 cmd/compile: fix export/import of range loop.
+ 2021-09-19 315dbd10c9 cmd/compile: fold double negate on arm64
+ 2021-09-19 83b36ffb10 cmd/compile: implement constant rotates on arm64
+ 2021-09-19 771b8ea4f4 cmd/compile: fix missing markHiddenClosureDead in deadcode pass
+ 2021-09-18 c894b442d1 net/rpc: remove warnings on incompatible methods at registration
+ 2021-09-17 4b654c0eec cmd/compile: SSA ".this" variable
+ 2021-09-17 f01721efb9 cmd/compile: remove self copies in tail-call wrappers
+ 2021-09-17 163871feb1 time: re-add space-padded day of year to docs
+ 2021-09-17 ac7c34767d time: support fractional timezone minutes in MarshalBinary
+ 2021-09-17 07b30a4f77 cmd/compile: delay transformAssign if lhs/rhs have typeparam
+ 2021-09-17 c10b980220 cmd/compile: restore tail call for method wrappers
+ 2021-09-17 50e4508269 cmd/compile: fix import/export of Init and Def fields.
+ 2021-09-17 3fa35b5f97 go/types: ensure that we always get a new signature in expandNamed
+ 2021-09-17 3fa7dbeff5 cmd/go: fix GOARCH value in GOAMD64 docs
+ 2021-09-17 974b0166d6 syscall: implement Pipe using pipe2 syscall on all linux platforms
+ 2021-09-17 1a49dcb82f syscall: remove //sysnb comment generating Setreuid for linux/arm64
+ 2021-09-17 cea7a71d40 cmd/compile: fix generic type handling in crawler
+ 2021-09-17 74e384f50d internal/poll: inject a hook into the runtime finalizer to count the closed pipes
+ 2021-09-17 323c6f74d3 log: don't format if writing to io.Discard
+ 2021-09-17 7f36ef0aff cmd/compile/internal/noder: hide TestUnifiedCompare behind -cmp flag
+ 2021-09-17 70493b3eb0 runtime/cgo: save and restore X3 (aka GP) for crosscall1 on riscv64
+ 2021-09-17 6d02ce8584 runtime: fix prettyprinting of parametric types in gdb
+ 2021-09-17 6602c86a38 cmd/internal/obj/riscv: improve instruction validation
+ 2021-09-17 14e812bfc5 syscall: do not use handle lists on windows when NoInheritHandles is true
+ 2021-09-16 8d2a9c32a2 all: remove incorrectly repeated words in comments
+ 2021-09-16 af9da137a9 A+C: update name to real name and add to AUTHORS
+ 2021-09-16 265b59aefd cmd/cgo: for godefs, don't let field prefix removal cause duplicates
+ 2021-09-16 4efdaa7bc7 testing: skip panics when picking the line number for decoration
+ 2021-09-16 e09dcc211a go/types, types2: add an additional shift test case
+ 2021-09-16 5402b4376c spec: fix incorrect type in a shift example
+ 2021-09-16 d09e09bc61 cmd/compile: fixing writebarrier.go for -G=3
+ 2021-09-16 bcdc61d830 cmd/compile: preserve statements better in expandCalls
+ 2021-09-16 48e2b1ea91 cmd/compile: fix LocResults formatting
+ 2021-09-16 b1bedc0774 cmd/go: add GOAMD64 environment variable
+ 2021-09-16 04f5116c98 cmd/go: clean paths before checking same directory
+ 2021-09-16 e7dbe3908e cmd/cgo: add missing tab in exports for a result of void
+ 2021-09-15 cfa233d76b cmd/compile: remove unneeded early transforms, with dictionary change
+ 2021-09-15 59a9a035ff cmd/compile: switch to computing dict format on instantiated functions
+ 2021-09-15 0edc6c4fa0 cmd/internal/obj/ppc64: generate prologue code compatible with new ABI
+ 2021-09-15 03df68d3c3 runtime: fix setting of cpu features for amd64
+ 2021-09-15 6196979365 cmd/go/internal/modload: prevent tidy downgrading disambiguating modules
+ 2021-09-15 72bb8185b5 cmd/compile: emit DWARF info about dictionary entries
+ 2021-09-15 5b48fca1fa cmd/compile: mark wrapper functions with DW_AT_trampoline
+ 2021-09-15 e4dfd788e6 go/internal/gcimporter,cmd/compile: minor clean-up in iimport.go
+ 2021-09-15 4847c47cb8 cmd/compile/internal/types2: eliminate Named.instPos
+ 2021-09-15 3100f54f20 cmd/compile/internal/types2: merge Named type loading and expansion
+ 2021-09-15 738cebb174 cmd/compile/internal/types2: implement Identical for *Union types
+ 2021-09-15 b26d325cb1 cmd/compile/internal/types2: remove some unnecessary loading/expansion of Named types
+ 2021-09-15 9fc28892cb cmd/compile/internal/types2: export TypeHash, return value without blanks
+ 2021-09-15 2da3375e9b runtime: in adjustTimers back up as far as necessary
+ 2021-09-15 c7f2f51fed cmd/go: remove subcommand prefix from error messages
+ 2021-09-15 0bb40b08c4 go/types: implement Identical for *Union types
+ 2021-09-15 cb4e1de021 go/types: minor cleanup of instantiation
+ 2021-09-15 a0f3129466 go/types: instantiate methods when instantiating Named types
+ 2021-09-14 bf26e43d0f go/types: eliminate Named.instPos
+ 2021-09-14 2933c451a0 go/types: merge Named type loading and expansion
+ 2021-09-14 137543bb93 cmd/compile: set IsShape based on type being in the Shapes pkg
+ 2021-09-14 3a72175cdc cmd/compile: fix test/typeparam/mdempsky/4.go for -G=3
+ 2021-09-14 b2c04f0d48 runtime: avoid loop variable capture in test
+ 2021-09-14 181e8cde30 go/internal/gcimporter: remove outdated comment
+ 2021-09-14 8699425b55 syscall: remove use of IN_KUBERNETES in test
+ 2021-09-14 b3c6de9dcd cmd/internal/obj/ppc64: allow VR register arguments to VS registers
+ 2021-09-14 ee91bb8319 cmd/compile: prevent typecheck importer reading type parameter twice
+ 2021-09-14 2953cd0083 go/internal/gcimporter: prevent importReader reading type parameter twice
+ 2021-09-14 b8c802b116 cmd/compile: prevent importReader reading type parameter twice
+ 2021-09-14 4a4221e818 all: remove some unused code
+ 2021-09-14 71adc658de runtime: change time.now to ABIInternal
+ 2021-09-14 146e8d4994 reflect: use Value.Len instead of conversion to slice header
+ 2021-09-13 9a58aa267e spec: fix prose about terminating statements
+ 2021-09-13 42057e9848 cmd/compile: save the note of fields when translating struct
+ 2021-09-13 960d036f8f cmd/go: add missing parenthesis in a call to "PrintVersion"
+ 2021-09-13 81a4fe6fd2 cmd/link/internal/ld: re-enable DWARF tests on solaris/illumos
+ 2021-09-13 f93a63addb reflect: add a floating point section to DeepEqual tests
+ 2021-09-13 a0c409cbc8 reflect: add fast paths for common, simple Kinds to DeepEqual
+ 2021-09-13 ac40c9872f reflect: fix _faststr optimization
+ 2021-09-13 c8a58f29dc cmd/go: add test to check for a potential workspace loading issue
+ 2021-09-13 e74e363a6b strings: add Clone function
+ 2021-09-13 bced369a50 cmd/link: minor code cleanup in dwarf gen
+ 2021-09-13 c3b217a0e5 cmd/go: document 'go install cmd@version' ignores vendor directories
+ 2021-09-12 ad97d204f0 go/types: remove some unnecessary loading/expansion of Named types
+ 2021-09-12 0d8a4bfc96 bufio: add Writer.AvailableBuffer
+ 2021-09-11 23832ba2e2 reflect: optimize for maps with string keys
+ 2021-09-11 a50225a0dc bufio: make Reader.Reset and Writer.Reset work on the zero value
+ 2021-09-10 cf2fe5d6f1 doc/asm: fix HTML markup
+ 2021-09-10 1bf2cd1291 debug/elf: retain original error message when getSymbols fails.
+ 2021-09-10 5a4b9f9494 time: reference -tags=timetzdata in testing panic
+ 2021-09-10 025308fe08 testing: increase alternation precedence
+ 2021-09-10 5a94a90d84 cmd/compile/internal/types2: better error message for invalid array decls
+ 2021-09-10 da1aa65053 cmd/compile/internal/syntax: correct follow token for type parameter lists
+ 2021-09-10 96ab854ab0 cmd/compile/internal: better AST line highlight in ssa.html
+ 2021-09-10 90c5660616 embed: guarantee the returned file of FS.Open implements io.Seeker
+ 2021-09-10 c69f5c0d76 cmd/compile: add support for Abs and Copysign intrinsics on riscv64
+ 2021-09-10 2091bd3f26 cmd/compile: simiplify arm64 bitfield optimizations
+ 2021-09-09 b32209d22d cmd/compile: fix test case for unified IR (fix build)
+ 2021-09-09 1a708bcf1d cmd/compile: don't crash while reporting invalid alias cycle
+ 2021-09-09 426ff3746f cmd/cgo, runtime/cgo: avoid GCC/clang conversion warnings
+ 2021-09-09 73483df406 cmd/compile/internal/syntax: better error message for missing type constraint
+ 2021-09-09 e1c3f2158f time: propagate "," separator for fractional seconds into Format
+ 2021-09-09 c981874a5a cmd/compile: fix implement for closure in a global assignment
+ 2021-09-09 2c4f389c02 cmd/link: enable internal linker in more cases for ppc64le
+ 2021-09-09 fb84e99eb7 test: add compiler regress tests for #46461
+ 2021-09-09 b9e1a24581 cmd/compile: fix case where init info of OAS node is dropped
+ 2021-09-09 f9271e4f85 go/types, types2: rename RParams -> RecvTypeParams
+ 2021-09-09 ea434450c2 reflect: add hooks for dealing with narrow width floats
+ 2021-09-09 a53e3d5f88 net: deprecate (net.Error).Temporary
+ 2021-09-09 19457a58e5 cmd/compile: stenciled conversions might be NOPs
+ 2021-09-09 a295b3cec8 test: re-enable AsmCheck tests for types2-based frontends
+ 2021-09-09 66f0d35f71 go/types: reduce number of delayed functions
+ 2021-09-09 d2a77f1c76 go/types: handle recursive type parameter constraints
+ 2021-09-09 9e1eea6f8b go/types: detect constraint type inference cycles
+ 2021-09-09 b86e8dd0f3 test/typeparam: fix issue48094b test build
+ 2021-09-09 c84f3a4004 syscall: drop fallback to pipe in Pipe on linux/arm
+ 2021-09-09 376a079762 cmd/compile: fix unified IR panic when expanding nested inline function
+ 2021-09-09 6edc57983a internal/poll: report open fds when TestSplicePipePool fails
+ 2021-09-09 2481f6e367 cmd/compile: fix wrong instantiated type for embedded receiver
+ 2021-09-09 d62866ef79 cmd/compile: move checkptr alignment to SSA generation
+ 2021-09-09 8fad81cd62 cmd/compile: fold handling OCONV logic to separate function
+ 2021-09-09 9cbc76bdf9 cmd/internal/obj/arm64: add checks for incorrect use of REGTMP register
+ 2021-09-09 42563f89d7 cmd/compile: remove 'ext' fields from unified IR reader/writer types
+ 2021-09-09 4c52eac49b cmd/compile: simplify value coding for unified IR
+ 2021-09-09 e30a09013b cmd/compile: extrapolate $GOROOT in unified IR
+ 2021-09-08 a1f6208e56 go/types, types2: add Environment to Config
+ 2021-09-08 f5f8a911d8 cmd/compile/internal/types2: spell out 'Type' in type parameter APIs
+ 2021-09-08 bff39cf6cb cmd/compile: add automated rewrite cycle detection
+ 2021-09-08 b61e1ed863 cmd/compile/internal/types2: temporarily pin the Checker to Interface during checking
+ 2021-09-08 47f3e1e02c cmd/compile/internal/types2: move NewTypeParam off of Checker
+ 2021-09-08 ccc927b8f6 cmd/compile/internal/types2: move typeHash to environment.go
+ 2021-09-08 30e9bfbcef cmd/compile/internal/types2: implement deduplication of instances using the Environment
+ 2021-09-08 0406d3a8e5 go/ast: rename MultiIndexExpr to IndexListExpr

Change-Id: I7f917d45b0507c122c212305144b0b455618ff54

1 files changed, 43 insertions, 24 deletions

diff --git a/src/cmd/compile/internal/typecheck/subr.go b/src/cmd/compile/internal/typecheck/subr.go
index 34f20879f1..d4af4e172e 100644
--- a/src/cmd/compile/internal/typecheck/subr.go
+++ b/src/cmd/compile/internal/typecheck/subr.go
@@ -352,7 +352,10 @@ func Assignop(src, dst *types.Type) (ir.Op, string) {
 	if types.Identical(src, dst) {
 		return ir.OCONVNOP, ""
 	}
+	return Assignop1(src, dst)
+}
 
+func Assignop1(src, dst *types.Type) (ir.Op, string) {
 	// 2. src and dst have identical underlying types and
 	//   a. either src or dst is not a named type, or
 	//   b. both are empty interface types, or
@@ -1019,10 +1022,11 @@ type Tsubster struct {
 	SubstForwFunc func(*types.Type) *types.Type
 }
 
-// Typ computes the type obtained by substituting any type parameter in t with the
-// corresponding type argument in subst. If t contains no type parameters, the
-// result is t; otherwise the result is a new type. It deals with recursive types
-// by using TFORW types and finding partially or fully created types via sym.Def.
+// Typ computes the type obtained by substituting any type parameter or shape in t
+// that appears in subst.Tparams with the corresponding type argument in subst.Targs.
+// If t contains no type parameters, the result is t; otherwise the result is a new
+// type. It deals with recursive types by using TFORW types and finding partially or
+// fully created types via sym.Def.
 func (ts *Tsubster) Typ(t *types.Type) *types.Type {
 	// Defer the CheckSize calls until we have fully-defined
 	// (possibly-recursive) top-level type.
@@ -1033,14 +1037,14 @@ func (ts *Tsubster) Typ(t *types.Type) *types.Type {
 }
 
 func (ts *Tsubster) typ1(t *types.Type) *types.Type {
-	if !t.HasTParam() && t.Kind() != types.TFUNC {
+	if !t.HasTParam() && !t.HasShape() && t.Kind() != types.TFUNC {
 		// Note: function types need to be copied regardless, as the
 		// types of closures may contain declarations that need
 		// to be copied. See #45738.
 		return t
 	}
 
-	if t.IsTypeParam() {
+	if t.IsTypeParam() || t.IsShape() {
 		for i, tp := range ts.Tparams {
 			if tp == t {
 				return ts.Targs[i]
@@ -1072,14 +1076,14 @@ func (ts *Tsubster) typ1(t *types.Type) *types.Type {
 	var targsChanged bool
 	var forw *types.Type
 
-	if t.Sym() != nil && t.HasTParam() {
+	if t.Sym() != nil && (t.HasTParam() || t.HasShape()) {
 		// Need to test for t.HasTParam() again because of special TFUNC case above.
 		// Translate the type params for this type according to
 		// the tparam/targs mapping from subst.
 		neededTargs = make([]*types.Type, len(t.RParams()))
 		for i, rparam := range t.RParams() {
 			neededTargs[i] = ts.typ1(rparam)
-			if !types.Identical(neededTargs[i], rparam) {
+			if !types.IdenticalStrict(neededTargs[i], rparam) {
 				targsChanged = true
 			}
 		}
@@ -1286,7 +1290,7 @@ func (ts *Tsubster) typ1(t *types.Type) *types.Type {
 // fields, set force to true.
 func (ts *Tsubster) tstruct(t *types.Type, force bool) *types.Type {
 	if t.NumFields() == 0 {
-		if t.HasTParam() {
+		if t.HasTParam() || t.HasShape() {
 			// For an empty struct, we need to return a new type,
 			// since it may now be fully instantiated (HasTParam
 			// becomes false).
@@ -1312,6 +1316,7 @@ func (ts *Tsubster) tstruct(t *types.Type, force bool) *types.Type {
 			// the type param, not the instantiated type).
 			newfields[i] = types.NewField(f.Pos, f.Sym, t2)
 			newfields[i].Embedded = f.Embedded
+			newfields[i].Note = f.Note
 			if f.IsDDD() {
 				newfields[i].SetIsDDD(true)
 			}
@@ -1387,19 +1392,20 @@ func genericTypeName(sym *types.Sym) string {
 	return sym.Name[0:strings.Index(sym.Name, "[")]
 }
 
-// Shapify takes a concrete type and returns a GCshape type that can
+// Shapify takes a concrete type and a type param index, and returns a GCshape type that can
 // be used in place of the input type and still generate identical code.
 // No methods are added - all methods calls directly on a shape should
 // be done by converting to an interface using the dictionary.
 //
-// TODO: this could take the generic function and base its decisions
-// on how that generic function uses this type argument. For instance,
-// if it doesn't use it as a function argument/return value, then
-// we don't need to distinguish int64 and float64 (because they only
-// differ in how they get passed as arguments). For now, we only
-// unify two different types if they are identical in every possible way.
-func Shapify(t *types.Type) *types.Type {
-	assert(!t.HasShape())
+// For now, we only consider two types to have the same shape, if they have exactly
+// the same underlying type or they are both pointer types.
+//
+//  Shape types are also distinguished by the index of the type in a type param/arg
+//  list. We need to do this so we can distinguish and substitute properly for two
+//  type params in the same function that have the same shape for a particular
+//  instantiation.
+func Shapify(t *types.Type, index int) *types.Type {
+	assert(!t.IsShape())
 	// Map all types with the same underlying type to the same shape.
 	u := t.Underlying()
 
@@ -1409,22 +1415,35 @@ func Shapify(t *types.Type) *types.Type {
 		u = types.Types[types.TUINT8].PtrTo()
 	}
 
-	if s := shaped[u]; s != nil {
+	if shapeMap == nil {
+		shapeMap = map[int]map[*types.Type]*types.Type{}
+	}
+	submap := shapeMap[index]
+	if submap == nil {
+		submap = map[*types.Type]*types.Type{}
+		shapeMap[index] = submap
+	}
+	if s := submap[u]; s != nil {
 		return s
 	}
 
-	sym := shapePkg.Lookup(u.LinkString())
+	nm := fmt.Sprintf("%s_%d", u.LinkString(), index)
+	sym := types.ShapePkg.Lookup(nm)
+	if sym.Def != nil {
+		// Use any existing type with the same name
+		submap[u] = sym.Def.Type()
+		return submap[u]
+	}
 	name := ir.NewDeclNameAt(u.Pos(), ir.OTYPE, sym)
 	s := types.NewNamed(name)
+	sym.Def = name
 	s.SetUnderlying(u)
 	s.SetIsShape(true)
 	s.SetHasShape(true)
 	name.SetType(s)
 	name.SetTypecheck(1)
-	shaped[u] = s
+	submap[u] = s
 	return s
 }
 
-var shaped = map[*types.Type]*types.Type{}
-
-var shapePkg = types.NewPkg(".shape", ".shape")
+var shapeMap map[int]map[*types.Type]*types.Type