1 files changed, 177 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/gc/compile.go b/src/cmd/compile/internal/gc/compile.go
new file mode 100644
index 0000000000..c2a6a9e327
--- /dev/null
+++ b/src/cmd/compile/internal/gc/compile.go
@@ -0,0 +1,177 @@
+// Copyright 2011 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 gc
+
+import (
+	"internal/race"
+	"math/rand"
+	"sort"
+	"sync"
+
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/compile/internal/liveness"
+	"cmd/compile/internal/reflectdata"
+	"cmd/compile/internal/ssagen"
+	"cmd/compile/internal/typecheck"
+	"cmd/compile/internal/types"
+)
+
+// "Portable" code generation.
+
+var (
+	compilequeue []*ir.Func // functions waiting to be compiled
+)
+
+func funccompile(fn *ir.Func) {
+	if ir.CurFunc != nil {
+		base.Fatalf("funccompile %v inside %v", fn.Sym(), ir.CurFunc.Sym())
+	}
+
+	if fn.Type() == nil {
+		if base.Errors() == 0 {
+			base.Fatalf("funccompile missing type")
+		}
+		return
+	}
+
+	// assign parameter offsets
+	types.CalcSize(fn.Type())
+
+	if len(fn.Body) == 0 {
+		// Initialize ABI wrappers if necessary.
+		ssagen.InitLSym(fn, false)
+		liveness.WriteFuncMap(fn)
+		return
+	}
+
+	typecheck.DeclContext = ir.PAUTO
+	ir.CurFunc = fn
+	compile(fn)
+	ir.CurFunc = nil
+	typecheck.DeclContext = ir.PEXTERN
+}
+
+func compile(fn *ir.Func) {
+	// Set up the function's LSym early to avoid data races with the assemblers.
+	// Do this before walk, as walk needs the LSym to set attributes/relocations
+	// (e.g. in markTypeUsedInInterface).
+	ssagen.InitLSym(fn, true)
+
+	errorsBefore := base.Errors()
+	walk(fn)
+	if base.Errors() > errorsBefore {
+		return
+	}
+
+	// From this point, there should be no uses of Curfn. Enforce that.
+	ir.CurFunc = nil
+
+	if ir.FuncName(fn) == "_" {
+		// We don't need to generate code for this function, just report errors in its body.
+		// At this point we've generated any errors needed.
+		// (Beyond here we generate only non-spec errors, like "stack frame too large".)
+		// See issue 29870.
+		return
+	}
+
+	// Make sure type syms are declared for all types that might
+	// be types of stack objects. We need to do this here
+	// because symbols must be allocated before the parallel
+	// phase of the compiler.
+	for _, n := range fn.Dcl {
+		switch n.Class_ {
+		case ir.PPARAM, ir.PPARAMOUT, ir.PAUTO:
+			if liveness.ShouldTrack(n) && n.Addrtaken() {
+				reflectdata.WriteType(n.Type())
+				// Also make sure we allocate a linker symbol
+				// for the stack object data, for the same reason.
+				if fn.LSym.Func().StackObjects == nil {
+					fn.LSym.Func().StackObjects = base.Ctxt.Lookup(fn.LSym.Name + ".stkobj")
+				}
+			}
+		}
+	}
+
+	if compilenow(fn) {
+		ssagen.Compile(fn, 0)
+	} else {
+		compilequeue = append(compilequeue, fn)
+	}
+}
+
+// compilenow reports whether to compile immediately.
+// If functions are not compiled immediately,
+// they are enqueued in compilequeue,
+// which is drained by compileFunctions.
+func compilenow(fn *ir.Func) bool {
+	// Issue 38068: if this function is a method AND an inline
+	// candidate AND was not inlined (yet), put it onto the compile
+	// queue instead of compiling it immediately. This is in case we
+	// wind up inlining it into a method wrapper that is generated by
+	// compiling a function later on in the Target.Decls list.
+	if ir.IsMethod(fn) && isInlinableButNotInlined(fn) {
+		return false
+	}
+	return base.Flag.LowerC == 1 && base.Debug.CompileLater == 0
+}
+
+// compileFunctions compiles all functions in compilequeue.
+// It fans out nBackendWorkers to do the work
+// and waits for them to complete.
+func compileFunctions() {
+	if len(compilequeue) != 0 {
+		types.CalcSizeDisabled = true // not safe to calculate sizes concurrently
+		if race.Enabled {
+			// Randomize compilation order to try to shake out races.
+			tmp := make([]*ir.Func, len(compilequeue))
+			perm := rand.Perm(len(compilequeue))
+			for i, v := range perm {
+				tmp[v] = compilequeue[i]
+			}
+			copy(compilequeue, tmp)
+		} else {
+			// Compile the longest functions first,
+			// since they're most likely to be the slowest.
+			// This helps avoid stragglers.
+			sort.Slice(compilequeue, func(i, j int) bool {
+				return len(compilequeue[i].Body) > len(compilequeue[j].Body)
+			})
+		}
+		var wg sync.WaitGroup
+		base.Ctxt.InParallel = true
+		c := make(chan *ir.Func, base.Flag.LowerC)
+		for i := 0; i < base.Flag.LowerC; i++ {
+			wg.Add(1)
+			go func(worker int) {
+				for fn := range c {
+					ssagen.Compile(fn, worker)
+				}
+				wg.Done()
+			}(i)
+		}
+		for _, fn := range compilequeue {
+			c <- fn
+		}
+		close(c)
+		compilequeue = nil
+		wg.Wait()
+		base.Ctxt.InParallel = false
+		types.CalcSizeDisabled = false
+	}
+}
+
+// isInlinableButNotInlined returns true if 'fn' was marked as an
+// inline candidate but then never inlined (presumably because we
+// found no call sites).
+func isInlinableButNotInlined(fn *ir.Func) bool {
+	if fn.Inl == nil {
+		return false
+	}
+	if fn.Sym() == nil {
+		return true
+	}
+	return !fn.Sym().Linksym().WasInlined()
+}