[dev.garbage] all: merge dev.cc (493ad916c3b1) into dev.garbage

TBR=austin
CC=golang-codereviews
https://golang.org/cl/179290043

.hgtags

@@ -136,3 +136,4 @@ f8b50ad4cac4d4c4ecf48324b4f512f65e82cc1c go1.3beta1
 f44017549ff9c3cc5eef74ebe7276cd0dfc066b6 go1.3.3
 f44017549ff9c3cc5eef74ebe7276cd0dfc066b6 release
 1fdfd7dfaedb1b7702141617e621ab7328a236a1 go1.4beta1
+bffdd0cae380ce1ccf3e98ed6b6cd53fece7ba72 go1.4rc1

AUTHORS

@@ -145,7 +145,7 @@ Egon Elbre <egonelbre@gmail.com>
 Ehren Kret <ehren.kret@gmail.com>
 Eivind Uggedal <eivind@uggedal.com>
 Elias Naur <elias.naur@gmail.com>
-Emil Hessman <c.emil.hessman@gmail.com>
+Emil Hessman <c.emil.hessman@gmail.com> <emil@hessman.se>
 Eoghan Sherry <ejsherry@gmail.com>
 Eric Clark <zerohp@gmail.com>
 Eric Milliken <emilliken@gmail.com>

CONTRIBUTORS

@@ -214,7 +214,7 @@ Egon Elbre <egonelbre@gmail.com>
 Ehren Kret <ehren.kret@gmail.com>
 Eivind Uggedal <eivind@uggedal.com>
 Elias Naur <elias.naur@gmail.com>
-Emil Hessman <c.emil.hessman@gmail.com>
+Emil Hessman <c.emil.hessman@gmail.com> <emil@hessman.se>
 Eoghan Sherry <ejsherry@gmail.com>
 Eric Clark <zerohp@gmail.com>
 Eric Milliken <emilliken@gmail.com>
@@ -452,6 +452,7 @@ Nicholas Katsaros <nick@nickkatsaros.com>
 Nicholas Presta <nick@nickpresta.ca> <nick1presta@gmail.com>
 Nicholas Sullivan <nicholas.sullivan@gmail.com>
 Nicholas Waples <nwaples@gmail.com>
+Nick Cooper <nmvc@google.com>
 Nick Craig-Wood <nick@craig-wood.com> <nickcw@gmail.com>
 Nicolas Kaiser <nikai@nikai.net>
 Nicolas Owens <mischief@offblast.org>

doc/go1.4.html

@@ -7,10 +7,10 @@
 <h2 id="introduction">Introduction to Go 1.4</h2>
 
 <p>
-The latest Go release, version 1.4, arrives as scheduled six months after 1.3
-and contains only one tiny language change,
-a possibly breaking change to the compiler,
-a backwards-compatible simple form of <code>for</code>-<code>range</code> loop.
+The latest Go release, version 1.4, arrives as scheduled six months after 1.3.
+It contains only one tiny language change,
+in the form of a backwards-compatible simple variant of <code>for</code>-<code>range</code> loop,
+and a possibly breaking change to the compiler involving methods on pointers-to-pointers.
 The release focuses primarily on implementation work, improving the garbage collector
 and preparing the ground for a fully concurrent collector to be rolled out in the
 next few releases.
@@ -20,7 +20,7 @@ this release therefore eliminates the notorious "hot stack split" problem.
 There are some new tools available including support in the <code>go</code> command
 for build-time source code generation.
 The release also adds support for ARM processors on Android and Native Client (NaCl)
-and AMD64 on Plan 9.
+and for AMD64 on Plan 9.
 As always, Go 1.4 keeps the <a href="/doc/go1compat.html">promise
 of compatibility</a>,
 and almost everything 
@@ -637,12 +637,29 @@ See the relevant package documentation for more information about each change.
 
 <ul>
 
+<li>
+The <a href="/pkg/archive/zip/"><code>archive/zip</code></a> package's
+<a href="/pkg/archive/zip/#Writer"><code>Writer</code></a> now supports a
+<a href="/pkg/archive/zip/#Writer.Flush"><code>Flush</code></a> method.
+</li>
+
 <li>
 The <a href="/pkg/compress/flate/"><code>compress/flate</code></a>,
 <a href="/pkg/compress/gzip/"><code>compress/gzip</code></a>,
 and <a href="/pkg/compress/zlib/"><code>compress/zlib</code></a>
 packages now support a <code>Reset</code> method
 for the decompressors, allowing them to reuse buffers and improve performance.
+The <a href="/pkg/compress/gzip/"><code>compress/gzip</code></a> package also has a
+<a href="/pkg/compress/gzip/#Reader.Multistream"><code>Multistream</code></a> method to control support
+for multistream files.
+</li>
+
+<li>
+The <a href="/pkg/crypto/"><code>crypto</code></a> package now has a
+<a href="/pkg/crypto/#Signer"><code>Signer</code></a> interface, implemented by the
+<code>PrivateKey</code> types in
+<a href="/pkg/crypto/ecdsa"><code>crypto/ecdsa</code></a> and
+<a href="/pkg/crypto/rsa"><code>crypto/rsa</code></a>.
 </li>
 
 <li>
@@ -665,6 +682,16 @@ to help clients detect fallback attacks.
 those attacks.)
 </li>
 
+<li>
+The <a href="/pkg/database/sql/"><code>database/sql</code></a> package can now list all registered
+<a href="/pkg/database/sql/#Drivers"><code>Drivers</code></a>.
+</li>
+
+<li>
+The <a href="/pkg/debug/dwarf/"><code>debug/dwarf</code></a> package now supports
+<a href="/pkg/debug/dwarf/#UnspecifiedType"><code>UnspecifiedType</code></a>s.
+</li>
+
 <li>
 In the <a href="/pkg/encoding/asn1/"><code>encoding/asn1</code></a> package,
 optional elements with a default value will now only be omitted if they have that value.
@@ -685,6 +712,11 @@ in some cases, especially involving arrays, it can be faster.
 There is no functional change.
 </li>
 
+<li>
+The <a href="/pkg/encoding/xml/"><code>encoding/xml</code></a> package's
+<a href="/pkg/encoding/xml/#Decoder"><code>Decoder</code></a> can now report its input offset.
+</li>
+
 <li>
 In the <a href="/pkg/fmt/"><code>fmt</code></a> package,
 formatting of pointers to maps has changed to be consistent with that of pointers
@@ -693,6 +725,28 @@ For instance, <code>&amp;map[string]int{"one":</code> <code>1}</code> now prints
 <code>&amp;map[one:</code> <code>1]</code> rather than as a hexadecimal pointer value.
 </li>
 
+<li>
+The <a href="/pkg/image/"><code>image</code></a> package's
+<a href="/pkg/image/#Image"><code>Image</code></a>
+implementations like
+<a href="/pkg/image/#RGBA"><code>RGBA</code></a> and
+<a href="/pkg/image/#Gray"><code>Gray</code></a> have specialized
+<a href="/pkg/image/#RGBA.RGBAAt"><code>RGBAAt</code></a> and
+<a href="/pkg/image/#Gray.GrayAt"><code>GrayAt</code></a> methods alongside the general
+<a href="/pkg/image/#Image.At"><code>At</code></a> method.
+</li>
+
+<li>
+The <a href="/pkg/image/png/"><code>image/png</code></a> package now has an
+<a href="/pkg/image/png/#Encoder"><code>Encoder</code></a>
+type to control the compression level used for encoding.
+</li>
+
+<li>
+The <a href="/pkg/math/"><code>math</code></a> package now has a
+<a href="/pkg/math/#Nextafter32"><code>Nextafter32</code><a/> function.
+</li>
+
 <li>
 The <a href="/pkg/net/http/"><code>net/http</code></a> package's
 <a href="/pkg/net/http/#Request"><code>Request</code></a> type
@@ -721,6 +775,7 @@ The <a href="/pkg/os/"><code>os</code></a> package
 now implements symbolic links on the Windows operating system
 through the <a href="/pkg/os/#Symlink"><code>Symlink</code></a> function.
 Other operating systems already have this functionality.
+There is also a new <a href="/pkg/os/#Unsetenv"><code>Unsetenv</code></a> function.
 </li>
 
 <li>

doc/go_spec.html

 <!--{
 	"Title": "The Go Programming Language Specification",
-	"Subtitle": "Version of October 27, 2014",
+	"Subtitle": "Version of November 11, 2014",
 	"Path": "/ref/spec"
 }-->
 
@@ -2521,30 +2521,40 @@ The following rules apply to selectors:
 <ol>
 <li>
 For a value <code>x</code> of type <code>T</code> or <code>*T</code>
-where <code>T</code> is not an interface type,
+where <code>T</code> is not a pointer or interface type,
 <code>x.f</code> denotes the field or method at the shallowest depth
 in <code>T</code> where there
 is such an <code>f</code>.
 If there is not exactly <a href="#Uniqueness_of_identifiers">one <code>f</code></a>
 with shallowest depth, the selector expression is illegal.
 </li>
+
 <li>
-For a variable <code>x</code> of type <code>I</code> where <code>I</code>
+For a value <code>x</code> of type <code>I</code> where <code>I</code>
 is an interface type, <code>x.f</code> denotes the actual method with name
-<code>f</code> of the value assigned to <code>x</code>.
+<code>f</code> of the dynamic value of <code>x</code>.
 If there is no method with name <code>f</code> in the
 <a href="#Method_sets">method set</a> of <code>I</code>, the selector
 expression is illegal.
 </li>
+
+<li>
+As an exception, if the type of <code>x</code> is a named pointer type
+and <code>(*x).f</code> is a valid selector expression denoting a field
+(but not a method), <code>x.f</code> is shorthand for <code>(*x).f</code>.
+</li>
+
 <li>
 In all other cases, <code>x.f</code> is illegal.
 </li>
+
 <li>
 If <code>x</code> is of pointer type and has the value
 <code>nil</code> and <code>x.f</code> denotes a struct field,
 assigning to or evaluating <code>x.f</code>
 causes a <a href="#Run_time_panics">run-time panic</a>.
 </li>
+
 <li>
 If <code>x</code> is of interface type and has the value
 <code>nil</code>, <a href="#Calls">calling</a> or
@@ -2553,18 +2563,6 @@ causes a <a href="#Run_time_panics">run-time panic</a>.
 </li>
 </ol>
 
-<p>
-Selectors automatically <a href="#Address_operators">dereference</a>
-pointers to structs.
-If <code>x</code> is a pointer to a struct, <code>x.y</code>
-is shorthand for <code>(*x).y</code>; if the field <code>y</code>
-is also a pointer to a struct, <code>x.y.z</code> is shorthand
-for <code>(*(*x).y).z</code>, and so on.
-If <code>x</code> contains an anonymous field of type <code>*A</code>,
-where <code>A</code> is also a struct type,
-<code>x.f</code> is shorthand for <code>(*x.A).f</code>.
-</p>
-
 <p>
 For example, given the declarations:
 </p>
@@ -2574,13 +2572,13 @@ type T0 struct {
 	x int
 }
 
-func (recv *T0) M0()
+func (*T0) M0()
 
 type T1 struct {
 	y int
 }
 
-func (recv T1) M1()
+func (T1) M1()
 
 type T2 struct {
 	z int
@@ -2588,9 +2586,13 @@ type T2 struct {
 	*T0
 }
 
-func (recv *T2) M2()
+func (*T2) M2()
 
-var p *T2  // with p != nil and p.T0 != nil
+type Q *T2
+
+var t T2     // with t.T0 != nil
+var p *T2    // with p != nil and (*p).T0 != nil
+var q Q = p
 </pre>
 
 <p>
@@ -2598,13 +2600,27 @@ one may write:
 </p>
 
 <pre>
+t.z          // t.z
+t.y          // t.T1.y
+t.x          // (*t.TO).x
+
 p.z          // (*p).z
-p.y   // ((*p).T1).y
+p.y          // (*p).T1.y
 p.x          // (*(*p).T0).x
 
-p.M2()  // (*p).M2()
-p.M1()  // ((*p).T1).M1()
-p.M0()  // ((*p).T0).M0()
+q.x          // (*(*q).T0).x        (*q).x is a valid field selector
+
+p.M2()       // p.M2()              M2 expects *T2 receiver
+p.M1()       // ((*p).T1).M1()      M1 expects T1 receiver
+p.M0()       // ((&(*p).T0)).M0()   M0 expects *T0 receiver, see section on Calls
+</pre>
+
+<p>
+but the following is invalid:
+</p>
+
+<pre>
+q.M0()       // (*q).M0 is valid but not a field selector
 </pre>
 
 

doc/install.html

@@ -47,7 +47,7 @@ proceeding. If your OS or architecture is not on the list, it's possible that
 <tr><td>FreeBSD 8 or later</td> <td>amd64, 386, arm</td> <td>Debian GNU/kFreeBSD not supported; FreeBSD/ARM needs FreeBSD 10 or later</td></tr>
 <tr><td>Linux 2.6.23 or later with glibc</td> <td>amd64, 386, arm</td> <td>CentOS/RHEL 5.x not supported; no binary distribution for ARM yet</td></tr>
 <tr><td>Mac OS X 10.6 or later</td> <td>amd64, 386</td> <td>use the gcc<sup>&#8224;</sup> that comes with Xcode<sup>&#8225;</sup></td></tr>
-<tr><td>Windows XP or later</td> <td>amd64, 386</td> <td>use MinGW gcc<sup>&#8224;</sup>. No need for cgywin or msys.</td></tr>
+<tr><td>Windows XP or later</td> <td>amd64, 386</td> <td>use MinGW gcc<sup>&#8224;</sup>. No need for cygwin or msys.</td></tr>
 </table>
 
 <p>

include/link.h

@@ -62,7 +62,7 @@ struct	Addr
 	short	type;
 	uint8	index;
 	int8	scale;
-	int8	reg;	// for 5l, 9l
+	int8	reg;	// for 5l, 9l; GPRs and FPRs both start at 0
 	int8	name; // for 5l, 9l
 	int8	class;	// for 5l, 9l
 	uint8	etype; // for 5g, 6g, 8g
@@ -94,6 +94,7 @@ struct	Prog
 	// operands
 	Addr	from;
 	uchar	reg; // arm, power64 only (e.g., ADD from, reg, to);
+		     // starts at 0 for both GPRs and FPRs;
 		     // also used for ADATA width on arm, power64
 	Addr	from3; // power64 only (e.g., RLWM/FMADD from, reg, from3, to)
 	Addr	to;
@@ -626,6 +627,11 @@ extern	char*	anames9[];
 extern	char*	cnames5[];
 extern	char*	cnames9[];
 
+extern	char*	dnames5[];
+extern	char*	dnames6[];
+extern	char*	dnames8[];
+extern	char*	dnames9[];
+
 extern	LinkArch	link386;
 extern	LinkArch	linkamd64;
 extern	LinkArch	linkamd64p32;
@@ -634,6 +640,7 @@ extern	LinkArch	linkpower64;
 extern	LinkArch	linkpower64le;
 
 #pragma	varargck	type	"A"	int
+#pragma	varargck	type	"E"	uint
 #pragma	varargck	type	"D"	Addr*
 #pragma	varargck	type	"lD"	Addr*
 #pragma	varargck	type	"P"	Prog*

misc/makerelease/makerelease.go

@@ -56,8 +56,8 @@ const (
 	blogPath       = "golang.org/x/blog"
 	toolPath       = "golang.org/x/tools"
 	tourPath       = "code.google.com/p/go-tour"
-	defaultToolTag = "release-branch.go1.3"
-	defaultTourTag = "release-branch.go1.3"
+	defaultToolTag = "release-branch.go1.4"
+	defaultTourTag = "release-branch.go1.4"
 )
 
 // Import paths for tool commands.

src/cmd/5g/opt.h

@@ -75,12 +75,18 @@ struct	Reg
 {
 	Flow	f;
 
-	Bits	set;  		// variables written by this instruction.
-	Bits	use1; 		// variables read by prog->from.
-	Bits	use2; 		// variables read by prog->to.
+	Bits	set;  		// regopt variables written by this instruction.
+	Bits	use1; 		// regopt variables read by prog->from.
+	Bits	use2; 		// regopt variables read by prog->to.
 
+	// refahead/refbehind are the regopt variables whose current
+	// value may be used in the following/preceding instructions
+	// up to a CALL (or the value is clobbered).
 	Bits	refbehind;
 	Bits	refahead;
+	// calahead/calbehind are similar, but for variables in
+	// instructions that are reachable after hitting at least one
+	// CALL.
 	Bits	calbehind;
 	Bits	calahead;
 	Bits	regdiff;
@@ -93,6 +99,16 @@ struct	Reg
 
 #define	NRGN	600
 /*c2go enum { NRGN = 600 }; */
+
+// A Rgn represents a single regopt variable over a region of code
+// where a register could potentially be dedicated to that variable.
+// The code encompassed by a Rgn is defined by the flow graph,
+// starting at enter, flood-filling forward while varno is refahead
+// and backward while varno is refbehind, and following branches.  A
+// single variable may be represented by multiple disjoint Rgns and
+// each Rgn may choose a different register for that variable.
+// Registers are allocated to regions greedily in order of descending
+// cost.
 struct	Rgn
 {
 	Reg*	enter;
@@ -144,7 +160,7 @@ void	prop(Reg*, Bits, Bits);
 void	synch(Reg*, Bits);
 uint32	allreg(uint32, Rgn*);
 void	paint1(Reg*, int);
-uint32	paint2(Reg*, int);
+uint32	paint2(Reg*, int, int);
 void	paint3(Reg*, int, uint32, int);
 void	addreg(Adr*, int);
 void	dumpit(char *str, Flow *r0, int);
@@ -187,16 +203,16 @@ enum
 	SizeF = 1<<7, // float aka float32
 	SizeD = 1<<8, // double aka float64
 
-	// Left side: address taken, read, write.
+	// Left side (Prog.from): address taken, read, write.
 	LeftAddr = 1<<9,
 	LeftRead = 1<<10,
 	LeftWrite = 1<<11,
 	
-	// Register in middle; never written.
+	// Register in middle (Prog.reg); only ever read.
 	RegRead = 1<<12,
 	CanRegRead = 1<<13,
 	
-	// Right side: address taken, read, write.
+	// Right side (Prog.to): address taken, read, write.
 	RightAddr = 1<<14,
 	RightRead = 1<<15,
 	RightWrite = 1<<16,

src/cmd/5g/reg.c

@@ -230,7 +230,7 @@ regopt(Prog *firstp)
 
 		/* the mod/div runtime routines smash R12 */
 		if(p->as == ADIV || p->as == ADIVU || p->as == AMOD || p->as == AMODU)
-			r->set.b[z] |= RtoB(12);
+			r->set.b[0] |= RtoB(12);
 	}
 	if(firstr == R)
 		return;
@@ -454,9 +454,13 @@ brk:
 	 * replace code (paint3)
 	 */
 	rgp = region;
+	if(debug['R'] && debug['v'])
+		print("\nregisterizing\n");
 	for(i=0; i<nregion; i++) {
+		if(debug['R'] && debug['v'])
+			print("region %d: cost %d varno %d enter %d\n", i, rgp->cost, rgp->varno, rgp->enter->f.prog->pc);
 		bit = blsh(rgp->varno);
-		vreg = paint2(rgp->enter, rgp->varno);
+		vreg = paint2(rgp->enter, rgp->varno, 0);
 		vreg = allreg(vreg, rgp);
 		if(debug['R']) {
 			if(rgp->regno >= NREG)
@@ -477,9 +481,6 @@ brk:
 		rgp++;
 	}
 
-	if(debug['R'] && debug['v'])
-		dumpit("pass6", &firstr->f, 1);
-
 	/*
 	 * free aux structures. peep allocates new ones.
 	 */
@@ -488,6 +489,15 @@ brk:
 	flowend(g);
 	firstr = R;
 
+	if(debug['R'] && debug['v']) {
+		// Rebuild flow graph, since we inserted instructions
+		g = flowstart(firstp, sizeof(Reg));
+		firstr = (Reg*)g->start;
+		dumpit("pass6", &firstr->f, 1);
+		flowend(g);
+		firstr = R;
+	}
+
 	/*
 	 * pass 7
 	 * peep-hole on basic block
@@ -1189,7 +1199,7 @@ paint1(Reg *r, int bn)
 }
 
 uint32
-paint2(Reg *r, int bn)
+paint2(Reg *r, int bn, int depth)
 {
 	Reg *r1;
 	int z;
@@ -1213,6 +1223,9 @@ paint2(Reg *r, int bn)
 		r = r1;
 	}
 	for(;;) {
+		if(debug['R'] && debug['v'])
+			print("  paint2 %d %P\n", depth, r->f.prog);
+
 		r->act.b[z] &= ~bb;
 
 		vreg |= r->regu;
@@ -1220,14 +1233,14 @@ paint2(Reg *r, int bn)
 		if(r->refbehind.b[z] & bb)
 			for(r1 = (Reg*)r->f.p2; r1 != R; r1 = (Reg*)r1->f.p2link)
 				if(r1->refahead.b[z] & bb)
-					vreg |= paint2(r1, bn);
+					vreg |= paint2(r1, bn, depth+1);
 
 		if(!(r->refahead.b[z] & bb))
 			break;
 		r1 = (Reg*)r->f.s2;
 		if(r1 != R)
 			if(r1->refbehind.b[z] & bb)
-				vreg |= paint2(r1, bn);
+				vreg |= paint2(r1, bn, depth+1);
 		r = (Reg*)r->f.s1;
 		if(r == R)
 			break;
@@ -1344,6 +1357,8 @@ RtoB(int r)
 int
 BtoR(uint32 b)
 {
+	// TODO Allow R0 and R1, but be careful with a 0 return
+	// TODO Allow R9. Only R10 is reserved now (just g, not m).
 	b &= 0x11fcL;	// excluded R9 and R10 for m and g, but not R12
 	if(b == 0)
 		return 0;
@@ -1442,12 +1457,14 @@ dumpit(char *str, Flow *r0, int isreg)
 				print(" (only)");
 			print("\n");
 		}
-//		r1 = r->s1;
-//		if(r1 != nil) {
-//			print("	succ:");
-//			for(; r1 != R; r1 = r1->s1)
-//				print(" %.4ud", (int)r1->prog->pc);
-//			print("\n");
-//		}
+		// Print successors if it's not just the next one
+		if(r->s1 != r->link || r->s2 != nil) {
+			print("	succ:");
+			if(r->s1 != nil)
+				print(" %.4ud", (int)r->s1->prog->pc);
+			if(r->s2 != nil)
+				print(" %.4ud", (int)r->s2->prog->pc);
+			print("\n");
+		}
 	}
 }

src/cmd/5l/5.out.h

@@ -338,6 +338,8 @@ enum
 	D_STATIC = (D_NONE+4),
 	D_AUTO = (D_NONE+5),
 	D_PARAM = (D_NONE+6),
+
+	D_LAST = (D_NONE+26),
 };
 
 /*

src/cmd/6g/opt.h

@@ -75,12 +75,18 @@ struct	Reg
 {
 	Flow	f;
 
-	Bits	set;  		// variables written by this instruction.
-	Bits	use1; 		// variables read by prog->from.
-	Bits	use2; 		// variables read by prog->to.
+	Bits	set;  		// regopt variables written by this instruction.
+	Bits	use1; 		// regopt variables read by prog->from.
+	Bits	use2; 		// regopt variables read by prog->to.
 
+	// refahead/refbehind are the regopt variables whose current
+	// value may be used in the following/preceding instructions
+	// up to a CALL (or the value is clobbered).
 	Bits	refbehind;
 	Bits	refahead;
+	// calahead/calbehind are similar, but for variables in
+	// instructions that are reachable after hitting at least one
+	// CALL.
 	Bits	calbehind;
 	Bits	calahead;
 	Bits	regdiff;
@@ -93,6 +99,16 @@ struct	Reg
 
 #define	NRGN	600
 /*c2go enum { NRGN = 600 }; */
+
+// A Rgn represents a single regopt variable over a region of code
+// where a register could potentially be dedicated to that variable.
+// The code encompassed by a Rgn is defined by the flow graph,
+// starting at enter, flood-filling forward while varno is refahead
+// and backward while varno is refbehind, and following branches.  A
+// single variable may be represented by multiple disjoint Rgns and
+// each Rgn may choose a different register for that variable.
+// Registers are allocated to regions greedily in order of descending
+// cost.
 struct	Rgn
 {
 	Reg*	enter;
@@ -140,7 +156,7 @@ void	prop(Reg*, Bits, Bits);
 void	synch(Reg*, Bits);
 uint32	allreg(uint32, Rgn*);
 void	paint1(Reg*, int);
-uint32	paint2(Reg*, int);
+uint32	paint2(Reg*, int, int);
 void	paint3(Reg*, int, uint32, int);
 void	addreg(Adr*, int);
 void	dumpone(Flow*, int);
@@ -165,8 +181,8 @@ typedef struct ProgInfo ProgInfo;
 struct ProgInfo
 {
 	uint32 flags; // the bits below
-	uint32 reguse; // required registers used by this instruction
-	uint32 regset; // required registers set by this instruction
+	uint32 reguse; // registers implicitly used by this instruction
+	uint32 regset; // registers implicitly set by this instruction
 	uint32 regindex; // registers used by addressing mode
 };
 
@@ -187,12 +203,12 @@ enum
 	SizeF = 1<<7, // float aka float32
 	SizeD = 1<<8, // double aka float64
 
-	// Left side: address taken, read, write.
+	// Left side (Prog.from): address taken, read, write.
 	LeftAddr = 1<<9,
 	LeftRead = 1<<10,
 	LeftWrite = 1<<11,
 	
-	// Right side: address taken, read, write.
+	// Right side (Prog.to): address taken, read, write.
 	RightAddr = 1<<12,
 	RightRead = 1<<13,
 	RightWrite = 1<<14,

src/cmd/6g/reg.c

@@ -389,9 +389,13 @@ brk:
 	 * replace code (paint3)
 	 */
 	rgp = region;
+	if(debug['R'] && debug['v'])
+		print("\nregisterizing\n");
 	for(i=0; i<nregion; i++) {
+		if(debug['R'] && debug['v'])
+			print("region %d: cost %d varno %d enter %d\n", i, rgp->cost, rgp->varno, rgp->enter->f.prog->pc);
 		bit = blsh(rgp->varno);
-		vreg = paint2(rgp->enter, rgp->varno);
+		vreg = paint2(rgp->enter, rgp->varno, 0);
 		vreg = allreg(vreg, rgp);
 		if(rgp->regno != 0) {
 			if(debug['R'] && debug['v']) {
@@ -406,9 +410,6 @@ brk:
 		rgp++;
 	}
 
-	if(debug['R'] && debug['v'])
-		dumpit("pass6", &firstr->f, 1);
-	
 	/*
 	 * free aux structures. peep allocates new ones.
 	 */
@@ -417,6 +418,15 @@ brk:
 	flowend(g);
 	firstr = R;
 
+	if(debug['R'] && debug['v']) {
+		// Rebuild flow graph, since we inserted instructions
+		g = flowstart(firstp, sizeof(Reg));
+		firstr = (Reg*)g->start;
+		dumpit("pass6", &firstr->f, 1);
+		flowend(g);
+		firstr = R;
+	}
+
 	/*
 	 * pass 7
 	 * peep-hole on basic block
@@ -1020,7 +1030,7 @@ paint1(Reg *r, int bn)
 }
 
 uint32
-paint2(Reg *r, int bn)
+paint2(Reg *r, int bn, int depth)
 {
 	Reg *r1;
 	int z;
@@ -1044,6 +1054,9 @@ paint2(Reg *r, int bn)
 		r = r1;
 	}
 	for(;;) {
+		if(debug['R'] && debug['v'])
+			print("  paint2 %d %P\n", depth, r->f.prog);
+
 		r->act.b[z] &= ~bb;
 
 		vreg |= r->regu;
@@ -1051,14 +1064,14 @@ paint2(Reg *r, int bn)
 		if(r->refbehind.b[z] & bb)
 			for(r1 = (Reg*)r->f.p2; r1 != R; r1 = (Reg*)r1->f.p2link)
 				if(r1->refahead.b[z] & bb)
-					vreg |= paint2(r1, bn);
+					vreg |= paint2(r1, bn, depth+1);
 
 		if(!(r->refahead.b[z] & bb))
 			break;
 		r1 = (Reg*)r->f.s2;
 		if(r1 != R)
 			if(r1->refbehind.b[z] & bb)
-				vreg |= paint2(r1, bn);
+				vreg |= paint2(r1, bn, depth+1);
 		r = (Reg*)r->f.s1;
 		if(r == R)
 			break;
@@ -1259,12 +1272,14 @@ dumpit(char *str, Flow *r0, int isreg)
 				print(" %.4ud", (int)r1->prog->pc);
 			print("\n");
 		}
-//		r1 = r->s1;
-//		if(r1 != R) {
-//			print("	succ:");
-//			for(; r1 != R; r1 = r1->s1)
-//				print(" %.4ud", (int)r1->prog->pc);
-//			print("\n");
-//		}
+		// Print successors if it's not just the next one
+		if(r->s1 != r->link || r->s2 != nil) {
+			print("	succ:");
+			if(r->s1 != nil)
+				print(" %.4ud", (int)r->s1->prog->pc);
+			if(r->s2 != nil)
+				print(" %.4ud", (int)r->s2->prog->pc);
+			print("\n");
+		}
 	}
 }

src/cmd/6l/6.out.h

@@ -865,6 +865,8 @@ enum
 
 	D_INDIR,	/* additive */
 
+	D_LAST,
+
 	T_TYPE		= 1<<0,
 	T_INDEX		= 1<<1,
 	T_OFFSET	= 1<<2,

src/cmd/8g/opt.h

@@ -75,12 +75,18 @@ struct	Reg
 {
 	Flow	f;
 
-	Bits	set;  		// variables written by this instruction.
-	Bits	use1; 		// variables read by prog->from.
-	Bits	use2; 		// variables read by prog->to.
+	Bits	set;  		// regopt variables written by this instruction.
+	Bits	use1; 		// regopt variables read by prog->from.
+	Bits	use2; 		// regopt variables read by prog->to.
 
+	// refahead/refbehind are the regopt variables whose current
+	// value may be used in the following/preceding instructions
+	// up to a CALL (or the value is clobbered).
 	Bits	refbehind;
 	Bits	refahead;
+	// calahead/calbehind are similar, but for variables in
+	// instructions that are reachable after hitting at least one
+	// CALL.
 	Bits	calbehind;
 	Bits	calahead;
 	Bits	regdiff;
@@ -106,6 +112,16 @@ struct	Reg
 
 #define	NRGN	600
 /*c2go enum { NRGN = 600 }; */
+
+// A Rgn represents a single regopt variable over a region of code
+// where a register could potentially be dedicated to that variable.
+// The code encompassed by a Rgn is defined by the flow graph,
+// starting at enter, flood-filling forward while varno is refahead
+// and backward while varno is refbehind, and following branches.  A
+// single variable may be represented by multiple disjoint Rgns and
+// each Rgn may choose a different register for that variable.
+// Registers are allocated to regions greedily in order of descending
+// cost.
 struct	Rgn
 {
 	Reg*	enter;
@@ -158,7 +174,7 @@ void	loopit(Reg*, int32);
 void	synch(Reg*, Bits);
 uint32	allreg(uint32, Rgn*);
 void	paint1(Reg*, int);
-uint32	paint2(Reg*, int);
+uint32	paint2(Reg*, int, int);
 void	paint3(Reg*, int, uint32, int);
 void	addreg(Adr*, int);
 void	dumpone(Flow*, int);
@@ -183,8 +199,8 @@ typedef struct ProgInfo ProgInfo;
 struct ProgInfo
 {
 	uint32 flags; // the bits below
-	uint32 reguse; // required registers used by this instruction
-	uint32 regset; // required registers set by this instruction
+	uint32 reguse; // registers implicitly used by this instruction
+	uint32 regset; // registers implicitly set by this instruction
 	uint32 regindex; // registers used by addressing mode
 };
 
@@ -205,12 +221,12 @@ enum
 	SizeF = 1<<7, // float aka float32
 	SizeD = 1<<8, // double aka float64
 
-	// Left side: address taken, read, write.
+	// Left side (Prog.from): address taken, read, write.
 	LeftAddr = 1<<9,
 	LeftRead = 1<<10,
 	LeftWrite = 1<<11,
 	
-	// Right side: address taken, read, write.
+	// Right side (Prog.to): address taken, read, write.
 	RightAddr = 1<<12,
 	RightRead = 1<<13,
 	RightWrite = 1<<14,

src/cmd/8g/reg.c

@@ -358,18 +358,19 @@ brk:
 	 * replace code (paint3)
 	 */
 	rgp = region;
+	if(debug['R'] && debug['v'])
+		print("\nregisterizing\n");
 	for(i=0; i<nregion; i++) {
+		if(debug['R'] && debug['v'])
+			print("region %d: cost %d varno %d enter %lld\n", i, rgp->cost, rgp->varno, rgp->enter->f.prog->pc);
 		bit = blsh(rgp->varno);
-		vreg = paint2(rgp->enter, rgp->varno);
+		vreg = paint2(rgp->enter, rgp->varno, 0);
 		vreg = allreg(vreg, rgp);
 		if(rgp->regno != 0)
 			paint3(rgp->enter, rgp->varno, vreg, rgp->regno);
 		rgp++;
 	}
 
-	if(debug['R'] && debug['v'])
-		dumpit("pass6", &firstr->f, 1);
-
 	/*
 	 * free aux structures. peep allocates new ones.
 	 */
@@ -378,6 +379,15 @@ brk:
 	flowend(g);
 	firstr = R;
 
+	if(debug['R'] && debug['v']) {
+		// Rebuild flow graph, since we inserted instructions
+		g = flowstart(firstp, sizeof(Reg));
+		firstr = (Reg*)g->start;
+		dumpit("pass6", &firstr->f, 1);
+		flowend(g);
+		firstr = R;
+	}
+
 	/*
 	 * pass 7
 	 * peep-hole on basic block
@@ -926,7 +936,7 @@ paint1(Reg *r, int bn)
 	Reg *r1;
 	Prog *p;
 	int z;
-	uint64 bb;
+	uint64 bb, rbz;
 
 	z = bn/64;
 	bb = 1LL<<(bn%64);
@@ -945,7 +955,8 @@ paint1(Reg *r, int bn)
 		r = r1;
 	}
 
-	if(LOAD(r) & ~(r->set.b[z]&~(r->use1.b[z]|r->use2.b[z])) & bb) {
+	rbz = ~(r->set.b[z]&~(r->use1.b[z]|r->use2.b[z]));
+	if(LOAD(r) & rbz & bb) {
 		change -= CLOAD * r->f.loop;
 	}
 	for(;;) {
@@ -996,7 +1007,7 @@ paint1(Reg *r, int bn)
 }
 
 uint32
-paint2(Reg *r, int bn)
+paint2(Reg *r, int bn, int depth)
 {
 	Reg *r1;
 	int z;
@@ -1020,6 +1031,9 @@ paint2(Reg *r, int bn)
 		r = r1;
 	}
 	for(;;) {
+		if(debug['R'] && debug['v'])
+			print("  paint2 %d %P\n", depth, r->f.prog);
+
 		r->act.b[z] &= ~bb;
 
 		vreg |= r->regu;
@@ -1027,14 +1041,14 @@ paint2(Reg *r, int bn)
 		if(r->refbehind.b[z] & bb)
 			for(r1 = (Reg*)r->f.p2; r1 != R; r1 = (Reg*)r1->f.p2link)
 				if(r1->refahead.b[z] & bb)
-					vreg |= paint2(r1, bn);
+					vreg |= paint2(r1, bn, depth+1);
 
 		if(!(r->refahead.b[z] & bb))
 			break;
 		r1 = (Reg*)r->f.s2;
 		if(r1 != R)
 			if(r1->refbehind.b[z] & bb)
-				vreg |= paint2(r1, bn);
+				vreg |= paint2(r1, bn, depth+1);
 		r = (Reg*)r->f.s1;
 		if(r == R)
 			break;
@@ -1053,7 +1067,7 @@ paint3(Reg *r, int bn, uint32 rb, int rn)
 	Reg *r1;
 	Prog *p;
 	int z;
-	uint64 bb;
+	uint64 bb, rbz;
 
 	z = bn/64;
 	bb = 1LL << (bn%64);
@@ -1072,7 +1086,8 @@ paint3(Reg *r, int bn, uint32 rb, int rn)
 		r = r1;
 	}
 
-	if(LOAD(r) & ~(r->set.b[z] & ~(r->use1.b[z]|r->use2.b[z])) & bb)
+	rbz = ~(r->set.b[z] & ~(r->use1.b[z]|r->use2.b[z]));
+	if(LOAD(r) & rbz & bb)
 		addmove(r, bn, rn, 0);
 	for(;;) {
 		r->act.b[z] |= bb;
@@ -1227,12 +1242,14 @@ dumpit(char *str, Flow *r0, int isreg)
 				print(" %.4ud", (int)r1->prog->pc);
 			print("\n");
 		}
-//		r1 = r->s1;
-//		if(r1 != nil) {
-//			print("	succ:");
-//			for(; r1 != R; r1 = r1->s1)
-//				print(" %.4ud", (int)r1->prog->pc);
-//			print("\n");
-//		}
+		// Print successors if it's not just the next one
+		if(r->s1 != r->link || r->s2 != nil) {
+			print("	succ:");
+			if(r->s1 != nil)
+				print(" %.4ud", (int)r->s1->prog->pc);
+			if(r->s2 != nil)
+				print(" %.4ud", (int)r->s2->prog->pc);
+			print("\n");
+		}
 	}
 }

src/cmd/8l/8.out.h

@@ -654,6 +654,8 @@ enum
 
 	D_CONST2 = D_INDIR+D_INDIR,
 
+	D_LAST,
+
 	T_TYPE		= 1<<0,
 	T_INDEX		= 1<<1,
 	T_OFFSET	= 1<<2,

src/cmd/9a/lex.c

@@ -250,7 +250,7 @@ struct
 	"R27",		LREG,	27,
 	"R28",		LREG,	28,
 	"R29",		LREG,	29,
-	"R30",		LREG,	30,
+	"g",		LREG,	30, // avoid unintentionally clobbering g using R30
 	"R31",		LREG,	31,
 
 	"F",		LF,	0,
@@ -488,6 +488,7 @@ struct
 	"SYSCALL",	LNOP, ASYSCALL,
 	"UNDEF",	LNOP, AUNDEF,
 
+	"RET",		LRETRN, ARETURN,
 	"RETURN",	LRETRN, ARETURN,
 	"RFI",		LRETRN,	ARFI,
 	"RFCI",		LRETRN,	ARFCI,

src/cmd/9c/Makefile

-# Copyright 2012 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.
-
-include ../../Make.dist

src/cmd/9c/Notes

--	effect of register expansion on 32-bit shifts and masks etc
-9c
--	multab
--	floating-point conversions
--	conversions of constants
--	nodtype for loads
--	sign-extension instruction (32-64) when in register?
--	double indexing
--	SLW (eg, in cat)
--	scheduling
-
-9l
--	D_QCONST, DWORD
--	maskgen

src/cmd/9c/doc.go

-// Copyright 2009 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.
-
-// +build ignore
-
-/*
-
-9c is a version of the Plan 9 C compiler.  The original is documented at
-
-	http://plan9.bell-labs.com/magic/man2html/1/8c
-
-Its target architecture is the Power64, referred to by these tools as
-power64 (big endian) or power64le (little endian).
-
-*/
-package main

src/cmd/9c/gc.h

-// cmd/9c/gc.h from Vita Nuova.
-//
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
-//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
-//	Portions Copyright © 1997-1999 Vita Nuova Limited
-//	Portions Copyright © 2000-2008 Vita Nuova Holdings Limited (www.vitanuova.com)
-//	Portions Copyright © 2004,2006 Bruce Ellis
-//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
-//	Revisions Copyright © 2000-2008 Lucent Technologies Inc. and others
-//	Portions Copyright © 2009 The Go Authors.  All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-#include	<u.h>
-#include	"../cc/cc.h"
-#include	"../9l/9.out.h"
-
-/*
- * 9c/powerpc64
- */
-#define	SZ_CHAR		1
-#define	SZ_SHORT	2
-#define	SZ_INT		4
-#define	SZ_LONG		4
-#define	SZ_IND		8
-#define	SZ_FLOAT	4
-#define	SZ_VLONG	8
-#define	SZ_DOUBLE	8
-#define	FNX		100
-
-typedef	struct	Case	Case;
-typedef	struct	C1	C1;
-typedef	struct	Multab	Multab;
-typedef	struct	Hintab	Hintab;
-typedef	struct	Reg	Reg;
-typedef	struct	Rgn	Rgn;
-
-#define	A	((Adr*)0)
-
-#define	INDEXED	9
-#define	P	((Prog*)0)
-
-struct	Case
-{
-	Case*	link;
-	vlong	val;
-	int32	label;
-	char	def;
-	char isv;
-};
-#define	C	((Case*)0)
-
-struct	C1
-{
-	vlong	val;
-	int32	label;
-};
-
-struct	Multab
-{
-	int32	val;
-	char	code[20];
-};
-
-struct	Hintab
-{
-	ushort	val;
-	char	hint[10];
-};
-
-struct	Reg
-{
-	int32	pc;
-	int32	rpo;		/* reverse post ordering */
-
-	Bits	set;
-	Bits	use1;
-	Bits	use2;
-
-	Bits	refbehind;
-	Bits	refahead;
-	Bits	calbehind;
-	Bits	calahead;
-	Bits	regdiff;
-	Bits	act;
-
-	int32	regu;
-	int32	loop;		/* could be shorter */
-
-	union
-	{
-		Reg*	log5;
-		int32	active;
-	};
-	Reg*	p1;
-	Reg*	p2;
-	Reg*	p2link;
-	Reg*	s1;
-	Reg*	s2;
-	Reg*	link;
-	Prog*	prog;
-};
-#define	R	((Reg*)0)
-
-#define	NRGN	600
-struct	Rgn
-{
-	Reg*	enter;
-	short	cost;
-	short	varno;
-	short	regno;
-};
-
-EXTERN	int32	breakpc;
-EXTERN	int32	nbreak;
-EXTERN	Case*	cases;
-EXTERN	Node	constnode;
-EXTERN	Node	fconstnode;
-EXTERN	Node	vconstnode;
-EXTERN	int32	continpc;
-EXTERN	int32	curarg;
-EXTERN	int32	cursafe;
-EXTERN	Prog*	lastp;
-extern	int	hintabsize;
-EXTERN	int32	maxargsafe;
-EXTERN	Multab	multab[20];
-EXTERN	int	mnstring;
-EXTERN	Node*	nodrat;
-EXTERN	Node*	nodret;
-EXTERN	Node*	nodsafe;
-EXTERN	int32	nrathole;
-EXTERN	int32	nstring;
-EXTERN	Prog*	p;
-EXTERN	int32	pc;
-EXTERN	Node	regnode;
-EXTERN	Node	qregnode;
-EXTERN	char	string[NSNAME];
-EXTERN	Sym*	symrathole;
-EXTERN	Node	znode;
-EXTERN	Prog	zprog;
-EXTERN	int	reg[NREG+NREG];
-EXTERN	int32	exregoffset;
-EXTERN	int32	exfregoffset;
-EXTERN	uchar	typechlpv[NTYPE];
-
-#define	BLOAD(r)	band(bnot(r->refbehind), r->refahead)
-#define	BSTORE(r)	band(bnot(r->calbehind), r->calahead)
-#define	LOAD(r)		(~r->refbehind.b[z] & r->refahead.b[z])
-#define	STORE(r)	(~r->calbehind.b[z] & r->calahead.b[z])
-
-#define	bset(a,n)	((a).b[(n)/32]&(1L<<(n)%32))
-
-#define	CLOAD	5
-#define	CREF	5
-#define	CINF	1000
-#define	LOOP	3
-
-EXTERN	Rgn	region[NRGN];
-EXTERN	Rgn*	rgp;
-EXTERN	int	nregion;
-EXTERN	int	nvar;
-
-EXTERN	Bits	externs;
-EXTERN	Bits	params;
-EXTERN	Bits	consts;
-EXTERN	Bits	addrs;
-
-EXTERN	int32	regbits;
-EXTERN	int32	exregbits;
-
-EXTERN	int	change;
-EXTERN	int	suppress;
-
-EXTERN	Reg*	firstr;
-EXTERN	Reg*	lastr;
-EXTERN	Reg	zreg;
-EXTERN	Reg*	freer;
-EXTERN	Var	var[NVAR];
-EXTERN	int32*	idom;
-EXTERN	Reg**	rpo2r;
-EXTERN	int32	maxnr;
-
-#define	R0ISZERO	(debug['0']==0)
-
-extern	char*	anames[];
-extern	Hintab	hintab[];
-
-/*
- * sgen.c
- */
-void	codgen(Node*, Node*);
-void	gen(Node*);
-void	usedset(Node*, int);
-void	noretval(int);
-void	xcom(Node*);
-int	bcomplex(Node*, Node*);
-Prog*	gtext(Sym*, int32);
-vlong	argsize(int);
-
-/*
- * cgen.c
- */
-void	cgen(Node*, Node*);
-void	reglcgen(Node*, Node*, Node*);
-void	lcgen(Node*, Node*);
-void	bcgen(Node*, int);
-void	boolgen(Node*, int, Node*);
-void	sugen(Node*, Node*, int32);
-void	layout(Node*, Node*, int, int, Node*);
-
-/*
- * txt.c
- */
-void	ginit(void);
-void	gclean(void);
-void	nextpc(void);
-void	gargs(Node*, Node*, Node*);
-void	garg1(Node*, Node*, Node*, int, Node**);
-Node*	nodconst(int32);
-Node*	nod32const(vlong);
-Node*	nodfconst(double);
-Node*	nodgconst(vlong v, Type *t);
-void	nodreg(Node*, Node*, int);
-void	regret(Node*, Node*, Type*, int);
-void	regalloc(Node*, Node*, Node*);
-void	regfree(Node*);
-void	regialloc(Node*, Node*, Node*);
-void	regsalloc(Node*, Node*);
-void	regaalloc1(Node*, Node*);
-void	regaalloc(Node*, Node*);
-void	regind(Node*, Node*);
-void	gprep(Node*, Node*);
-void	raddr(Node*, Prog*);
-void	naddr(Node*, Addr*);
-void	gmove(Node*, Node*);
-void	gins(int a, Node*, Node*);
-void	gopcode(int, Node*, Node*, Node*);
-int	samaddr(Node*, Node*);
-void	gbranch(int);
-int	immconst(Node*);
-void	patch(Prog*, int32);
-int	sconst(Node*);
-int	sval(int32);
-int	uconst(Node*);
-void	gpseudo(int, Sym*, Node*);
-void	gprefetch(Node*);
-void	gpcdata(int, int);
-
-/*
- * swt.c
- */
-int	swcmp(const void*, const void*);
-void	doswit(Node*);
-void	swit1(C1*, int, int32, Node*);
-void	swit2(C1*, int, int32, Node*, Node*);
-void	newcase(void);
-void	bitload(Node*, Node*, Node*, Node*, Node*);
-void	bitstore(Node*, Node*, Node*, Node*, Node*);
-int32	outstring(char*, int32);
-int	mulcon(Node*, Node*);
-Multab*	mulcon0(Node*, int32);
-int	mulcon1(Node*, int32, Node*);
-void	nullwarn(Node*, Node*);
-void	sextern(Sym*, Node*, int32, int32);
-void	gextern(Sym*, Node*, int32, int32);
-void	outcode(void);
-
-/*
- * list
- */
-void	listinit(void);
-int	Pconv(Fmt*);
-int	Aconv(Fmt*);
-int	Dconv(Fmt*);
-int	Sconv(Fmt*);
-int	Nconv(Fmt*);
-int	Bconv(Fmt*);
-
-/*
- * reg.c
- */
-Reg*	rega(void);
-int	rcmp(const void*, const void*);
-void	regopt(Prog*);
-void	addmove(Reg*, int, int, int);
-Bits	mkvar(Addr*, int);
-void	prop(Reg*, Bits, Bits);
-void	loopit(Reg*, int32);
-void	synch(Reg*, Bits);
-uint32	allreg(uint32, Rgn*);
-void	paint1(Reg*, int);
-uint32	paint2(Reg*, int);
-void	paint3(Reg*, int, int32, int);
-void	addreg(Addr*, int);
-
-/*
- * peep.c
- */
-void	peep(void);
-void	excise(Reg*);
-Reg*	uniqp(Reg*);
-Reg*	uniqs(Reg*);
-int	regtyp(Addr*);
-int	regzer(Addr*);
-int	anyvar(Addr*);
-int	subprop(Reg*);
-int	copyprop(Reg*);
-int	copy1(Addr*, Addr*, Reg*, int);
-int	copyu(Prog*, Addr*, Addr*);
-
-int	copyas(Addr*, Addr*);
-int	copyau(Addr*, Addr*);
-int	copyau1(Prog*, Addr*);
-int	copysub(Addr*, Addr*, Addr*, int);
-int	copysub1(Prog*, Addr*, Addr*, int);
-
-int32	RtoB(int);
-int32	FtoB(int);
-int	BtoR(int32);
-int	BtoF(int32);
-
-/*
- * com64.c
- */
-int	com64(Node*);
-void	com64init(void);
-void	bool64(Node*);
-
-#pragma	varargck	type	"A"	int
-#pragma	varargck	type	"B"	Bits
-#pragma	varargck	type	"D"	Addr*
-#pragma	varargck	type	"N"	Addr*
-#pragma	varargck	type	"P"	Prog*
-#pragma	varargck	type	"S"	char*

src/cmd/9c/list.c

-// cmd/9c/list.c from Vita Nuova.
-//
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
-//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
-//	Portions Copyright © 1997-1999 Vita Nuova Limited
-//	Portions Copyright © 2000-2008 Vita Nuova Holdings Limited (www.vitanuova.com)
-//	Portions Copyright © 2004,2006 Bruce Ellis
-//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
-//	Revisions Copyright © 2000-2008 Lucent Technologies Inc. and others
-//	Portions Copyright © 2009 The Go Authors.  All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-#define EXTERN
-#include "gc.h"
-
-void
-listinit(void)
-{
-	listinit9();
-}

src/cmd/9c/machcap.c

-// cmd/9c/machcap.c from Vita Nuova.
-//
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
-//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
-//	Portions Copyright © 1997-1999 Vita Nuova Limited
-//	Portions Copyright © 2000-2008 Vita Nuova Holdings Limited (www.vitanuova.com)
-//	Portions Copyright © 2004,2006 Bruce Ellis
-//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
-//	Revisions Copyright © 2000-2008 Lucent Technologies Inc. and others
-//	Portions Copyright © 2009 The Go Authors.  All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-#include "gc.h"
-
-int
-machcap(Node *n)
-{
-
-	if(n == Z)
-		return 1;	/* test */
-
-	switch(n->op) {
-	case OMUL:
-	case OLMUL:
-	case OASMUL:
-	case OASLMUL:
-		if(typechlv[n->type->etype])
-			return 1;
-		break;
-
-	case OADD:
-	case OAND:
-	case OOR:
-	case OSUB:
-	case OXOR:
-	case OASHL:
-	case OLSHR:
-	case OASHR:
-		if(typechlv[n->left->type->etype])
-			return 1;
-		break;
-
-	case OCAST:
-		return 1;
-
-	case OCOND:
-	case OCOMMA:
-	case OLIST:
-	case OANDAND:
-	case OOROR:
-	case ONOT:
-		return 1;
-
-	case OASADD:
-	case OASSUB:
-	case OASAND:
-	case OASOR:
-	case OASXOR:
-		return 1;
-
-	case OASASHL:
-	case OASASHR:
-	case OASLSHR:
-		return 1;
-
-	case OPOSTINC:
-	case OPOSTDEC:
-	case OPREINC:
-	case OPREDEC:
-		return 1;
-
-	case OEQ:
-	case ONE:
-	case OLE:
-	case OGT:
-	case OLT:
-	case OGE:
-	case OHI:
-	case OHS:
-	case OLO:
-	case OLS:
-		return 1;
-	case ONEG:
-	case OCOM:
-		break;
-	}
-	return 0;
-}

src/cmd/9c/sgen.c

-// cmd/9c/sgen.c from Vita Nuova.
-//
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
-//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
-//	Portions Copyright © 1997-1999 Vita Nuova Limited
-//	Portions Copyright © 2000-2008 Vita Nuova Holdings Limited (www.vitanuova.com)
-//	Portions Copyright © 2004,2006 Bruce Ellis
-//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
-//	Revisions Copyright © 2000-2008 Lucent Technologies Inc. and others
-//	Portions Copyright © 2009 The Go Authors.  All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-#include "gc.h"
-
-Prog*
-gtext(Sym *s, int32 stkoff)
-{
-	vlong v;
-
-	v = ((uvlong)argsize(1) << 32) | (stkoff & 0xffffffff);
-	if((textflag & NOSPLIT) && stkoff >= 128)
-		yyerror("stack frame too large for NOSPLIT function");
-
-	gpseudo(ATEXT, s, nodgconst(v, types[TVLONG]));
-	return p;
-}
-
-
-void
-noretval(int n)
-{
-
-	if(n & 1) {
-		gins(ANOP, Z, Z);
-		p->to.type = D_REG;
-		p->to.reg = REGRET;
-	}
-	if(n & 2) {
-		gins(ANOP, Z, Z);
-		p->to.type = D_FREG;
-		p->to.reg = FREGRET;
-	}
-}
-
-/*
- *	calculate addressability as follows
- *		CONST ==> 20		$value
- *		NAME ==> 10		name
- *		REGISTER ==> 11		register
- *		INDREG ==> 12		*[(reg)+offset]
- *		&10 ==> 2		$name
- *		ADD(2, 20) ==> 2	$name+offset
- *		ADD(3, 20) ==> 3	$(reg)+offset
- *		&12 ==> 3		$(reg)+offset
- *		*11 ==> 11		??
- *		*2 ==> 10		name
- *		*3 ==> 12		*(reg)+offset
- *	calculate complexity (number of registers)
- */
-void
-xcom(Node *n)
-{
-	Node *l, *r;
-	int v;
-
-	if(n == Z)
-		return;
-	l = n->left;
-	r = n->right;
-	n->addable = 0;
-	n->complex = 0;
-	switch(n->op) {
-	case OCONST:
-		n->addable = 20;
-		return;
-
-	case OREGISTER:
-		n->addable = 11;
-		return;
-
-	case OINDREG:
-		n->addable = 12;
-		return;
-
-	case ONAME:
-		n->addable = 10;
-		return;
-
-	case OADDR:
-		xcom(l);
-		if(l->addable == 10)
-			n->addable = 2;
-		if(l->addable == 12)
-			n->addable = 3;
-		break;
-
-	case OIND:
-		xcom(l);
-		if(l->addable == 11)
-			n->addable = 12;
-		if(l->addable == 3)
-			n->addable = 12;
-		if(l->addable == 2)
-			n->addable = 10;
-		break;
-
-	case OADD:
-		xcom(l);
-		xcom(r);
-		if(l->addable == 20) {
-			if(r->addable == 2)
-				n->addable = 2;
-			if(r->addable == 3)
-				n->addable = 3;
-		}
-		if(r->addable == 20) {
-			if(l->addable == 2)
-				n->addable = 2;
-			if(l->addable == 3)
-				n->addable = 3;
-		}
-		break;
-
-	case OASMUL:
-	case OASLMUL:
-		xcom(l);
-		xcom(r);
-		v = vlog(r);
-		if(v >= 0) {
-			n->op = OASASHL;
-			r->vconst = v;
-			r->type = types[TINT];
-		}
-		break;
-
-	case OMUL:
-	case OLMUL:
-		xcom(l);
-		xcom(r);
-		v = vlog(r);
-		if(v >= 0) {
-			n->op = OASHL;
-			r->vconst = v;
-			r->type = types[TINT];
-		}
-		v = vlog(l);
-		if(v >= 0) {
-			n->op = OASHL;
-			n->left = r;
-			n->right = l;
-			r = l;
-			l = n->left;
-			r->vconst = v;
-			r->type = types[TINT];
-			simplifyshift(n);
-		}
-		break;
-
-	case OASLDIV:
-		xcom(l);
-		xcom(r);
-		v = vlog(r);
-		if(v >= 0) {
-			n->op = OASLSHR;
-			r->vconst = v;
-			r->type = types[TINT];
-		}
-		break;
-
-	case OLDIV:
-		xcom(l);
-		xcom(r);
-		v = vlog(r);
-		if(v >= 0) {
-			n->op = OLSHR;
-			r->vconst = v;
-			r->type = types[TINT];
-			simplifyshift(n);
-		}
-		break;
-
-	case OASLMOD:
-		xcom(l);
-		xcom(r);
-		v = vlog(r);
-		if(v >= 0) {
-			n->op = OASAND;
-			r->vconst--;
-		}
-		break;
-
-	case OLMOD:
-		xcom(l);
-		xcom(r);
-		v = vlog(r);
-		if(v >= 0) {
-			n->op = OAND;
-			r->vconst--;
-		}
-		break;
-
-	case OLSHR:
-	case OASHL:
-	case OASHR:
-		xcom(l);
-		xcom(r);
-		simplifyshift(n);
-		break;
-
-	default:
-		if(l != Z)
-			xcom(l);
-		if(r != Z)
-			xcom(r);
-		break;
-	}
-	if(n->addable >= 10)
-		return;
-	if(l != Z)
-		n->complex = l->complex;
-	if(r != Z) {
-		if(r->complex == n->complex)
-			n->complex = r->complex+1;
-		else
-		if(r->complex > n->complex)
-			n->complex = r->complex;
-	}
-	if(n->complex == 0)
-		n->complex++;
-
-//	if(com64(n))
-//		return;
-
-	switch(n->op) {
-
-	case OFUNC:
-		n->complex = FNX;
-		break;
-
-	case OEQ:
-	case ONE:
-	case OLE:
-	case OLT:
-	case OGE:
-	case OGT:
-	case OHI:
-	case OHS:
-	case OLO:
-	case OLS:
-		/*
-		 * immediate operators, make const on right
-		 */
-		if(l->op == OCONST) {
-			n->left = r;
-			n->right = l;
-			n->op = invrel[relindex(n->op)];
-		}
-		break;
-
-	case OADD:
-	case OXOR:
-	case OAND:
-	case OOR:
-		/*
-		 * immediate operators, make const on right
-		 */
-		if(l->op == OCONST) {
-			n->left = r;
-			n->right = l;
-		}
-		break;
-	}
-}
-

src/cmd/9c/swt.c

-// cmd/9c/swt.c from Vita Nuova.
-//
-//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
-//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
-//	Portions Copyright © 1997-1999 Vita Nuova Limited
-//	Portions Copyright © 2000-2008 Vita Nuova Holdings Limited (www.vitanuova.com)
-//	Portions Copyright © 2004,2006 Bruce Ellis
-//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
-//	Revisions Copyright © 2000-2008 Lucent Technologies Inc. and others
-//	Portions Copyright © 2009 The Go Authors.  All rights reserved.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-#include "gc.h"
-
-void
-swit1(C1 *q, int nc, int32 def, Node *n)
-{
-	Node tn, nod;
-
-	regalloc(&nod, n, Z);
-	/* always signed */
-	if(typev[n->type->etype])
-		nod.type = types[TVLONG];
-	else
-		nod.type = types[TLONG];
-	cgen(n, &nod);
-	regalloc(&tn, &regnode, Z);
-	swit2(q, nc, def, &nod, &tn);
-	regfree(&tn);
-	regfree(&nod);
-}
-
-void
-swit2(C1 *q, int nc, int32 def, Node *n, Node *tn)
-{
-	C1 *r;
-	int i;
-	Prog *sp;
-
-	if(nc < 5) {
-		for(i=0; i<nc; i++) {
-			if(sval(q->val)) {
-				gopcode(OEQ, n, Z, nodconst(q->val));
-			} else {
-				gopcode(OSUB, nodconst(q->val), n, tn);
-				gopcode(OEQ, tn, Z, nodconst(0));
-			}
-			patch(p, q->label);
-			q++;
-		}
-		gbranch(OGOTO);
-		patch(p, def);
-		return;
-	}
-	i = nc / 2;
-	r = q+i;
-	if(sval(r->val)) {
-		gopcode(OGT, n, Z, nodconst(r->val));
-		sp = p;
-	} else {
-		gopcode(OSUB, nodconst(r->val), n, tn);
-		gopcode(OGT, tn, Z, nodconst(0));
-		sp = p;
-	}
-	gbranch(OGOTO);
-	p->as = ABEQ;
-	patch(p, r->label);
-	swit2(q, i, def, n, tn);
-
-	patch(sp, pc);
-	swit2(r+1, nc-i-1, def, n, tn);
-}
-
-void
-bitload(Node *b, Node *n1, Node *n2, Node *n3, Node *nn)
-{
-	int sh;
-	int32 v;
-	Node *l;
-
-	/*
-	 * n1 gets adjusted/masked value
-	 * n2 gets address of cell
-	 * n3 gets contents of cell
-	 */
-	l = b->left;
-	if(n2 != Z) {
-		regalloc(n1, l, nn);
-		reglcgen(n2, l, Z);
-		regalloc(n3, l, Z);
-		gopcode(OAS, n2, Z, n3);
-		gopcode(OAS, n3, Z, n1);
-	} else {
-		regalloc(n1, l, nn);
-		cgen(l, n1);
-	}
-	if(b->type->shift == 0 && typeu[b->type->etype]) {
-		v = ~0 + (1L << b->type->nbits);
-		gopcode(OAND, nodconst(v), Z, n1);
-	} else {
-		sh = 32 - b->type->shift - b->type->nbits;
-		if(sh > 0)
-			gopcode(OASHL, nodconst(sh), Z, n1);
-		sh += b->type->shift;
-		if(sh > 0)
-			if(typeu[b->type->etype])
-				gopcode(OLSHR, nodconst(sh), Z, n1);
-			else
-				gopcode(OASHR, nodconst(sh), Z, n1);
-	}
-}
-
-void
-bitstore(Node *b, Node *n1, Node *n2, Node *n3, Node *nn)
-{
-	int32 v;
-	Node nod, *l;
-	int sh;
-
-	/*
-	 * n1 has adjusted/masked value
-	 * n2 has address of cell
-	 * n3 has contents of cell
-	 */
-	l = b->left;
-	regalloc(&nod, l, Z);
-	v = ~0 + (1L << b->type->nbits);
-	gopcode(OAND, nodconst(v), Z, n1);
-	gopcode(OAS, n1, Z, &nod);
-	if(nn != Z)
-		gopcode(OAS, n1, Z, nn);
-	sh = b->type->shift;
-	if(sh > 0)
-		gopcode(OASHL, nodconst(sh), Z, &nod);
-	v <<= sh;
-	gopcode(OAND, nodconst(~v), Z, n3);
-	gopcode(OOR, n3, Z, &nod);
-	gopcode(OAS, &nod, Z, n2);
-
-	regfree(&nod);
-	regfree(n1);
-	regfree(n2);
-	regfree(n3);
-}
-
-int32
-outstring(char *s, int32 n)
-{
-	int32 r;
-
-	if(suppress)
-		return nstring;
-	r = nstring;
-	while(n) {
-		string[mnstring] = *s++;
-		mnstring++;
-		nstring++;
-		if(mnstring >= NSNAME) {
-			gpseudo(ADATA, symstring, nodconst(0L));
-			p->from.offset += nstring - NSNAME;
-			p->reg = NSNAME;
-			p->to.type = D_SCONST;
-			memmove(p->to.u.sval, string, NSNAME);
-			mnstring = 0;
-		}
-		n--;
-	}
-	return r;
-}
-
-int
-mulcon(Node *n, Node *nn)
-{
-	Node *l, *r, nod1, nod2;
-	Multab *m;
-	int32 v;
-	int o;
-	char code[sizeof(m->code)+2], *p;
-
-	if(typefd[n->type->etype])
-		return 0;
-	l = n->left;
-	r = n->right;
-	if(l->op == OCONST) {
-		l = r;
-		r = n->left;
-	}
-	if(r->op != OCONST)
-		return 0;
-	v = convvtox(r->vconst, n->type->etype);
-	if(v != r->vconst) {
-		if(debug['M'])
-			print("%L multiply conv: %lld\n", n->lineno, r->vconst);
-		return 0;
-	}
-	m = mulcon0(n, v);
-	if(!m) {
-		if(debug['M'])
-			print("%L multiply table: %lld\n", n->lineno, r->vconst);
-		return 0;
-	}
-
-	memmove(code, m->code, sizeof(m->code));
-	code[sizeof(m->code)] = 0;
-
-	p = code;
-	if(p[1] == 'i')
-		p += 2;
-	regalloc(&nod1, n, nn);
-	cgen(l, &nod1);
-	if(v < 0)
-		gopcode(ONEG, &nod1, Z, &nod1);
-	regalloc(&nod2, n, Z);
-
-loop:
-	switch(*p) {
-	case 0:
-		regfree(&nod2);
-		gopcode(OAS, &nod1, Z, nn);
-		regfree(&nod1);
-		return 1;
-	case '+':
-		o = OADD;
-		goto addsub;
-	case '-':
-		o = OSUB;
-	addsub:	/* number is r,n,l */
-		v = p[1] - '0';
-		r = &nod1;
-		if(v&4)
-			r = &nod2;
-		n = &nod1;
-		if(v&2)
-			n = &nod2;
-		l = &nod1;
-		if(v&1)
-			l = &nod2;
-		gopcode(o, l, n, r);
-		break;
-	default: /* op is shiftcount, number is r,l */
-		v = p[1] - '0';
-		r = &nod1;
-		if(v&2)
-			r = &nod2;
-		l = &nod1;
-		if(v&1)
-			l = &nod2;
-		v = *p - 'a';
-		if(v < 0 || v >= 32) {
-			diag(n, "mulcon unknown op: %c%c", p[0], p[1]);
-			break;
-		}
-		gopcode(OASHL, nodconst(v), l, r);
-		break;
-	}
-	p += 2;
-	goto loop;
-}
-
-void
-sextern(Sym *s, Node *a, int32 o, int32 w)
-{
-	int32 e, lw;
-
-	for(e=0; e<w; e+=NSNAME) {
-		lw = NSNAME;
-		if(w-e < lw)
-			lw = w-e;
-		gpseudo(ADATA, s, nodconst(0));
-		p->from.offset += o+e;
-		p->reg = lw;
-		p->to.type = D_SCONST;
-		memmove(p->to.u.sval, a->cstring+e, lw);
-	}
-}
-
-void
-gextern(Sym *s, Node *a, int32 o, int32 w)
-{
-	gpseudo(ADATA, s, a);
-	p->from.offset += o;
-	p->reg = w;
-	if(p->to.type == D_OREG)
-		p->to.type = D_CONST;
-}
-
-void
-outcode(void)
-{
-	Bprint(&outbuf, "go object %s %s %s\n", getgoos(), getgoarch(), getgoversion());
-	if(pragcgobuf.to > pragcgobuf.start) {
-		Bprint(&outbuf, "\n");
-		Bprint(&outbuf, "$$  // exports\n\n");
-		Bprint(&outbuf, "$$  // local types\n\n");
-		Bprint(&outbuf, "$$  // cgo\n");
-		Bprint(&outbuf, "%s", fmtstrflush(&pragcgobuf));
-		Bprint(&outbuf, "\n$$\n\n");
-	}
-	Bprint(&outbuf, "!\n");
-
-	writeobj(ctxt, &outbuf);
-	lastp = nil;
-}
-
-int32
-align(int32 i, Type *t, int op, int32 *maxalign)
-{
-	int32 o;
-	Type *v;
-	int w, packw;
-
-	o = i;
-	w = 1;
-	packw = 0;
-	switch(op) {
-	default:
-		diag(Z, "unknown align opcode %d", op);
-		break;
-
-	case Asu2:	/* padding at end of a struct */
-		w = *maxalign;
-		if(w < 1)
-			w = 1;
-		if(packflg)
-			packw = packflg;
-		break;
-
-	case Ael1:	/* initial allign of struct element */
-		for(v=t; v->etype==TARRAY; v=v->link)
-			;
-		if(v->etype == TSTRUCT || v->etype == TUNION)
-			w = v->align;
-		else
-			w = ewidth[v->etype];
-		if(w < 1 || w > SZ_VLONG)
-			fatal(Z, "align");
-		if(packflg)
-			packw = packflg;
-		break;
-
-	case Ael2:	/* width of a struct element */
-		o += t->width;
-		break;
-
-	case Aarg0:	/* initial passbyptr argument in arg list */
-		if(typesu[t->etype]) {
-			o = align(o, types[TIND], Aarg1, nil);
-			o = align(o, types[TIND], Aarg2, nil);
-		}
-		break;
-
-	case Aarg1:	/* initial align of parameter */
-		w = ewidth[t->etype];
-		if(w <= 0 || w >= SZ_VLONG) {
-			w = SZ_VLONG;
-			break;
-		}
-		w = 1;
-		break;
-
-	case Aarg2:	/* width of a parameter */
-		o += t->width;
-		w = t->width;
-		if(w > SZ_VLONG)
-			w = SZ_VLONG;
-		break;
-
-	case Aaut3:	/* total align of automatic */
-		o = align(o, t, Ael1, nil);
-		o = align(o, t, Ael2, nil);
-		break;
-	}
-	if(packw != 0 && xround(o, w) != xround(o, packw))
-		diag(Z, "#pragma pack changes offset of %T", t);
-	o = xround(o, w);
-	if(maxalign && *maxalign < w)
-		*maxalign = w;
-	if(debug['A'])
-		print("align %s %ld %T = %ld\n", bnames[op], i, t, o);
-	return o;
-}
-
-int32
-maxround(int32 max, int32 v)
-{
-	v = xround(v, SZ_VLONG);
-	if(v > max)
-		return v;
-	return max;
-}

src/cmd/9g/prog.c

@@ -134,11 +134,12 @@ proginfo(ProgInfo *info, Prog *p)
 	}
 
 	if(p->as == ADUFFZERO) {
-		info->reguse |= RtoB(0) | RtoB(2);
-		info->regset |= RtoB(2);
+		info->reguse |= (1<<D_R0) | RtoB(3);
+		info->regset |= RtoB(3);
 	}
 	if(p->as == ADUFFCOPY) {
-		info->reguse |= RtoB(0) | RtoB(2) | RtoB(3);
-		info->regset |= RtoB(2) | RtoB(3);
+		// TODO(austin) Revisit when duffcopy is implemented
+		info->reguse |= RtoB(3) | RtoB(4) | RtoB(5);
+		info->regset |= RtoB(3) | RtoB(4);
 	}
 }

src/cmd/9l/9.out.h

@@ -497,6 +497,8 @@ enum
 	D_DCONST,
 	D_ADDR, // not used, use D_CONST with non-empty sym.
 
+	D_LAST,
+
 /* reg names for 9g OREGISTER */
 	D_R0 = 0, // type is D_REG
 	D_F0 = D_R0+NREG, // type is D_FREG