Starting to build xform2 to use the new IR format

Author: rj45

TODO.md

@@ -182,6 +182,7 @@
     - [x] Get it to parse programs to ir2
     - [x] Handle translating tuples to multiple return values
   - [x] Can emit IR code in a way that simplifies text, assembly and html generation
+    - [ ] Emits to ssa.html
   - [ ] Implement a simplified type system
     - [ ] integer types i/u 8,16,32,64
     - [ ] bool type
@@ -232,6 +233,21 @@
     - [ ] Refactor: better package naming
       - [ ] Generate unique package names
       - [ ] Identifiers in other packages are pkg_name.ident rather than pkg_name__ident
+    - [ ] Use github.com/nochso/ctxerr for error messages
+  - [ ] Transform xform pkg to use new IR
+    - [x] Register func with options for config
+      - [x] grabs name from passed xform func
+      - [x] tags
+      - [x] list of active stages
+      - [x] activating op
+      - [x] can be run on each instr
+      - [ ] can be run on each block
+      - [x] takes a func that takes an iterator
+        - [x] xform func responsible for leaving iterator in a resumable position
+        - [x] iterator tracks changes
+          - [x] ability to tell the iterator a change was made it can't see
+    - [ ] A way to run a single transform for testing w/tags
+    - [ ] A way to run a single stage for testing w/tags
 
 - [ ] Rework xform system
 

compiler/compiler.go

@@ -21,6 +21,9 @@ import (
 	"github.com/rj45/nanogo/parser"
 	"github.com/rj45/nanogo/regalloc"
 	"github.com/rj45/nanogo/xform"
+	"github.com/rj45/nanogo/xform2"
+
+	_ "github.com/rj45/nanogo/xform2/elaboration"
 )
 
 type Arch interface {
@@ -121,6 +124,8 @@ func Compile(outname, dir string, patterns []string, mode Mode) int {
 		fe.Scan()
 		for fn := fe.NextUnparsedFunc(); fn != nil; fn = fe.NextUnparsedFunc() {
 			fe.ParseFunc(fn)
+
+			xform2.Transform(xform2.Elaboration, fn)
 		}
 
 		fe.Program().Emit(finalout, ir2.SSAString{})

ir2/instr.go

@@ -116,7 +116,7 @@ func (in *Instr) Args() []*Value {
 
 // NumArgs returns the number of arguments
 func (in *Instr) NumArgs() int {
-	return len(in.defs)
+	return len(in.args)
 }
 
 // ArgIndex returns the index of the arg, or

ir2/iters.go

@@ -4,12 +4,61 @@ import (
 	"go/types"
 )
 
+// Iter is a iterator over instructions
+type Iter interface {
+	// Instr returns the current instruction
+	Instr() *Instr
+
+	// InstrIndex returns the index of the current instruction in the Block
+	InstrIndex() int
+
+	// Block returns the current block
+	Block() *Block
+
+	// BlockIndex returns the index of the Block within the Func
+	BlockIndex() int
+
+	// HasNext returns whether Next() will succeed
+	HasNext() bool
+
+	// Next increments the position and returns whether that was successful
+	Next() bool
+
+	// HasPrev returns whether Prev() will succeed
+	HasPrev() bool
+
+	// Prev decrements the position and returns whether that was successful
+	Prev() bool
+
+	// Insert inserts an instruction at the cursor position and increments the position
+	Insert(op Op, typ types.Type, args ...interface{}) *Instr
+
+	// Remove will remove the instruction at the current position and decrement the position,
+	// returning the removed instruction.
+	// NOTE: this only removes the instruction from the Block, it does not Unlink() it from
+	// any uses.
+	Remove() *Instr
+
+	// Update updates the instruction at the cursor position
+	Update(op Op, typ types.Type, args ...interface{}) *Instr
+
+	// HasChanged returns true if `Changed()` was called, or one of the mutation methods
+	HasChanged() bool
+
+	// Changed forces `HasChanged()` to return true
+	Changed()
+}
+
+var _ Iter = &BlockIter{}
+var _ Iter = &CrossBlockIter{}
+
 /// in-block iterator
 
 // BlockIter is an iterator that iterates over instructions in a Block
 type BlockIter struct {
-	blk    *Block
-	insIdx int
+	blk     *Block
+	insIdx  int
+	changed bool
 }
 
 // InstrIter will return an Iter which iterates over every
@@ -74,13 +123,25 @@ func (it *BlockIter) HasPrev() bool {
 	return it.insIdx >= 0 // todo: there is a bug here
 }
 
+// HasChanged returns true if `Changed()` was called, or one of the mutation methods
+func (it *BlockIter) HasChanged() bool {
+	return it.changed
+}
+
+// Changed forces `HasChanged()` to return true
+func (it *BlockIter) Changed() {
+	it.changed = true
+}
+
 // Insert inserts an instruction at the cursor position and increments the position
 func (it *BlockIter) Insert(op Op, typ types.Type, args ...interface{}) *Instr {
 	instr := it.blk.fn.NewInstr(op, typ, args...)
 
 	it.blk.InsertInstr(it.insIdx, instr)
 	it.Next()
 
+	it.changed = true
+
 	return instr
 }
 
@@ -95,6 +156,8 @@ func (it *BlockIter) Remove() *Instr {
 	it.blk.RemoveInstr(instr)
 	it.Prev()
 
+	it.changed = true
+
 	return instr
 }
 
@@ -104,6 +167,8 @@ func (it *BlockIter) Update(op Op, typ types.Type, args ...interface{}) *Instr {
 
 	instr.Update(op, typ, args...)
 
+	it.changed = true
+
 	return instr
 }
 
@@ -128,24 +193,25 @@ func (fn *Func) InstrIter() *CrossBlockIter {
 
 // HasNext returns whether Next() will succeed
 func (it *CrossBlockIter) HasNext() bool {
-	return it.insIdx < len(it.blk.instrs) && it.blkIdx < len(it.fn.blocks)
+	return (it.insIdx+1) < len(it.blk.instrs) || (it.blkIdx+1) < len(it.fn.blocks)
 }
 
 // Next increments the position and returns whether that was successful
 func (it *CrossBlockIter) Next() bool {
-	if it.insIdx >= len(it.blk.instrs) {
-		if (it.blkIdx + 1) >= len(it.fn.blocks) {
-			return false
-		}
+	if !it.HasNext() {
+		return false
+	}
+
+	it.insIdx++
 
+	if it.insIdx >= len(it.blk.instrs) {
 		it.blkIdx++
 		it.insIdx = 0
 		it.blk = it.fn.blocks[it.blkIdx]
 		return true
 	}
 
-	it.insIdx++
-	return it.insIdx < len(it.blk.instrs)
+	return true
 }
 
 // HasPrev returns whether Prev() will succeed

ir2/structs.go

@@ -163,6 +163,7 @@ const (
 	VFunc
 	VTemp
 	VReg
+	VArg
 	VStack
 	VGlob
 	VHeap

xform2/elaboration/calls.go

@@ -0,0 +1,87 @@
+package elaboration
+
+import (
+	"go/types"
+	"log"
+
+	"github.com/rj45/nanogo/ir/op"
+	"github.com/rj45/nanogo/ir/reg"
+	"github.com/rj45/nanogo/ir2"
+	"github.com/rj45/nanogo/xform2"
+)
+
+var _ = xform2.Register(calls,
+	xform2.OnlyPass(xform2.Elaboration),
+	xform2.OnOp(op.Call),
+)
+
+func calls(it ir2.Iter) {
+	instr := it.Instr()
+	fnType := instr.Arg(0).Type.(*types.Signature)
+
+	if instr.NumArgs() > 1 && instr.Arg(1).Def() != nil && instr.Arg(1).Def().Op == op.Copy {
+		log.Println("arg copy already done")
+		return
+	}
+
+	if instr.NumDefs() > 0 && instr.Def(0).NumUses() == 1 && instr.Def(0).Use(0).Op == op.Copy {
+		log.Println("result copy already done")
+		return
+	}
+
+	// todo:
+	// - add parallel copy for clobbered regs?
+
+	if instr.NumArgs() > 1 {
+		params := fnType.Params()
+
+		args := make([]interface{}, instr.NumArgs()-1)
+		for i := 1; i < instr.NumArgs(); i++ {
+			args[i-1] = instr.Arg(i)
+		}
+
+		paramCopy := it.Insert(op.Copy, params, args...)
+		log.Println(paramCopy.LongString())
+		for i := 0; i < paramCopy.NumDefs(); i++ {
+			if i < len(reg.ArgRegs) {
+				paramCopy.Def(i).Loc = ir2.VReg
+				paramCopy.Def(i).Index = reg.ArgRegs[i].RegNumber()
+			} else {
+				paramCopy.Def(i).Loc = ir2.VArg
+				paramCopy.Def(i).Index = i - len(reg.ArgRegs)
+			}
+			instr.ReplaceArg(i+1, paramCopy.Def(i))
+		}
+	}
+
+	if instr.NumDefs() > 0 {
+		results := fnType.Results()
+
+		args := make([]interface{}, instr.NumDefs())
+		for i := 0; i < instr.NumDefs(); i++ {
+			args[i] = instr.Def(i)
+		}
+
+		it.Next()
+		resCopy := it.Insert(op.Copy, results, args...)
+		log.Println(resCopy.LongString())
+		for i := 0; i < resCopy.NumArgs(); i++ {
+			if i < len(reg.ArgRegs) {
+				resCopy.Arg(i).Loc = ir2.VReg
+				resCopy.Arg(i).Index = reg.ArgRegs[i].RegNumber()
+			} else {
+				resCopy.Arg(i).Loc = ir2.VArg
+				resCopy.Arg(i).Index = i - len(reg.ArgRegs)
+			}
+
+			// todo: could use a version of this that doesn't
+			// clobber the current instruction or something
+			instr.Def(i).ReplaceUsesWith(resCopy.Def(i))
+
+			// switch this back to what it was
+			resCopy.ReplaceArg(i, instr.Def(i))
+		}
+	}
+
+	log.Println(instr.LongString())
+}

xform2/tag.go

@@ -0,0 +1,25 @@
+package xform2
+
+type Tag uint8
+
+const (
+	Invalid Tag = iota
+	HasFramePointer
+
+	// ...
+
+	NumTags
+)
+
+var activeTags []bool
+
+type Arch interface {
+	XformTags() []Tag
+}
+
+func SetArch(a Arch) {
+	activeTags = make([]bool, NumTags)
+	for _, tag := range a.XformTags() {
+		activeTags[tag] = true
+	}
+}