[dev.ssa] cmd/compile: default compile+test with SSA

Some tests disabled, some bifurcated into _ssa and not,
with appropriate logging added to compiler.

"tests/live.go" in particular needs attention.

SSA-specific testing removed, since it's all SSA now.

Added "-run_skips" option to tests/run.go to simplify
checking whether a test still fails (or how it fails)
on a skipped platform.

The compiler now compiles with SSA by default.
If you don't want SSA, specify GOSSAHASH=n (or N) as
an environment variable.  Function names ending in "_ssa"
are always SSA-compiled.

GOSSAFUNC=fname retains its "SSA for fname, log to ssa.html"
GOSSAPKG=pkg only has an effect when GOSSAHASH=n
GOSSAHASH=10101 etc retains its name-hash-matching behavior
for purposes of debugging.

See #13068

Change-Id: I8217bfeb34173533eaeb391b5f6935483c7d6b43
Reviewed-on: https://go-review.googlesource.com/16299
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>

1 files changed, 50 insertions, 49 deletions

diff --git a/test/nilcheck.go b/test/nilcheck.go
index 99c3c5fdb6..173fcb33a6 100644
--- a/test/nilcheck.go
+++ b/test/nilcheck.go
@@ -1,3 +1,4 @@
+// +build !amd64
 // errorcheck -0 -N -d=nil
 
 // Copyright 2013 The Go Authors.  All rights reserved.
@@ -17,7 +18,7 @@ type Struct struct {
 type BigStruct struct {
 	X int
 	Y float64
-	A [1<<20]int
+	A [1 << 20]int
 	Z string
 }
 
@@ -29,86 +30,86 @@ type Empty1 struct {
 }
 
 var (
-	intp *int
-	arrayp *[10]int
-	array0p *[0]int
-	bigarrayp *[1<<26]int
-	structp *Struct
+	intp       *int
+	arrayp     *[10]int
+	array0p    *[0]int
+	bigarrayp  *[1 << 26]int
+	structp    *Struct
 	bigstructp *BigStruct
-	emptyp *Empty
-	empty1p *Empty1
+	emptyp     *Empty
+	empty1p    *Empty1
 )
 
 func f1() {
-	_ = *intp // ERROR "nil check"
-	_ = *arrayp // ERROR "nil check"
+	_ = *intp    // ERROR "nil check"
+	_ = *arrayp  // ERROR "nil check"
 	_ = *array0p // ERROR "nil check"
 	_ = *array0p // ERROR "nil check"
-	_ = *intp // ERROR "nil check"
-	_ = *arrayp // ERROR "nil check"
+	_ = *intp    // ERROR "nil check"
+	_ = *arrayp  // ERROR "nil check"
 	_ = *structp // ERROR "nil check"
-	_ = *emptyp // ERROR "nil check"
-	_ = *arrayp // ERROR "nil check"
+	_ = *emptyp  // ERROR "nil check"
+	_ = *arrayp  // ERROR "nil check"
 }
 
 func f2() {
 	var (
-		intp *int
-		arrayp *[10]int
-		array0p *[0]int
-		bigarrayp *[1<<20]int
-		structp *Struct
+		intp       *int
+		arrayp     *[10]int
+		array0p    *[0]int
+		bigarrayp  *[1 << 20]int
+		structp    *Struct
 		bigstructp *BigStruct
-		emptyp *Empty
-		empty1p *Empty1
+		emptyp     *Empty
+		empty1p    *Empty1
 	)
 
-	_ = *intp // ERROR "nil check"
-	_ = *arrayp // ERROR "nil check"
-	_ = *array0p // ERROR "nil check"
-	_ = *array0p // ERROR "nil check"
-	_ = *intp // ERROR "nil check"
-	_ = *arrayp // ERROR "nil check"
-	_ = *structp // ERROR "nil check"
-	_ = *emptyp // ERROR "nil check"
-	_ = *arrayp // ERROR "nil check"
-	_ = *bigarrayp // ERROR "nil check"
+	_ = *intp       // ERROR "nil check"
+	_ = *arrayp     // ERROR "nil check"
+	_ = *array0p    // ERROR "nil check"
+	_ = *array0p    // ERROR "nil check"
+	_ = *intp       // ERROR "nil check"
+	_ = *arrayp     // ERROR "nil check"
+	_ = *structp    // ERROR "nil check"
+	_ = *emptyp     // ERROR "nil check"
+	_ = *arrayp     // ERROR "nil check"
+	_ = *bigarrayp  // ERROR "nil check"
 	_ = *bigstructp // ERROR "nil check"
-	_ = *empty1p // ERROR "nil check"
+	_ = *empty1p    // ERROR "nil check"
 }
 
 func fx10k() *[10000]int
-var b bool
 
+var b bool
 
 func f3(x *[10000]int) {
 	// Using a huge type and huge offsets so the compiler
 	// does not expect the memory hardware to fault.
 	_ = x[9999] // ERROR "nil check"
-	
+
 	for {
 		if x[9999] != 0 { // ERROR "nil check"
 			break
 		}
 	}
-	
-	x = fx10k() 
+
+	x = fx10k()
 	_ = x[9999] // ERROR "nil check"
 	if b {
 		_ = x[9999] // ERROR "nil check"
 	} else {
 		_ = x[9999] // ERROR "nil check"
-	}	
+	}
 	_ = x[9999] // ERROR "nil check"
 
-	x = fx10k() 
+	x = fx10k()
 	if b {
 		_ = x[9999] // ERROR "nil check"
 	} else {
 		_ = x[9999] // ERROR "nil check"
-	}	
+	}
 	_ = x[9999] // ERROR "nil check"
-	
+
 	fx10k()
 	// This one is a bit redundant, if we figured out that
 	// x wasn't going to change across the function call.
@@ -138,7 +139,7 @@ func f3b() {
 	_ = &x[9] // ERROR "nil check"
 }
 
-func fx10() *[10]int 
+func fx10() *[10]int
 
 func f4(x *[10]int) {
 	// Most of these have no checks because a real memory reference follows,
@@ -146,33 +147,33 @@ func f4(x *[10]int) {
 	// in the first unmapped page of memory.
 
 	_ = x[9] // ERROR "nil check"
-	
+
 	for {
 		if x[9] != 0 { // ERROR "nil check"
 			break
 		}
 	}
-	
-	x = fx10() 
+
+	x = fx10()
 	_ = x[9] // ERROR "nil check"
 	if b {
 		_ = x[9] // ERROR "nil check"
 	} else {
 		_ = x[9] // ERROR "nil check"
-	}	
+	}
 	_ = x[9] // ERROR "nil check"
 
-	x = fx10() 
+	x = fx10()
 	if b {
 		_ = x[9] // ERROR "nil check"
 	} else {
 		_ = &x[9] // ERROR "nil check"
-	}	
+	}
 	_ = x[9] // ERROR "nil check"
-	
+
 	fx10()
 	_ = x[9] // ERROR "nil check"
-	
+
 	x = fx10()
 	y := fx10()
 	_ = &x[9] // ERROR "nil check"