cmd/internal/obj/arm64: fix handling of unaligned offset between 256 and 504

C_PPAUTO was matching offsets that is a multiple 8. But this
condition is dropped in CL 55610, causing unaligned offset
between 256 and 504 mistakenly matched to some classes, e.g.
C_UAUTO8K. This CL restores this condition, also fixes an
error that C_PPAUTO shouldn't match C_PSAUTO, because the
latter is not guaranteed to be multiple of 8. C_PPAUTO_8 is
unnecessary, removed.

Fixes #21992.

Change-Id: I75d5a0e5f5dc3dae335721fbec1bbcd4a3b862f2
Reviewed-on: https://go-review.googlesource.com/65730
Reviewed-by: David Chase <drchase@google.com>

diff --git a/src/cmd/internal/obj/arm64/a.out.go b/src/cmd/internal/obj/arm64/a.out.go
index 9f225b6f5de709ea7289dd3befd5bb3614cd29e1..c4bd8ff39e4c49f4532206709cf5d630197ba9d4 100644 (file)
--- a/src/cmd/internal/obj/arm64/a.out.go
+++ b/src/cmd/internal/obj/arm64/a.out.go
@@ -293,8 +293,7 @@ const (
        C_NSAUTO     // -256 <= x < 0
        C_PSAUTO_8   // 0 to 255, 0 mod 8
        C_PSAUTO     // 0 to 255
-       C_PPAUTO_8   // 0 to 504, 0 mod 8
-       C_PPAUTO     // 0 to 504
+       C_PPAUTO     // 0 to 504, 0 mod 8
        C_UAUTO4K_8  // 0 to 4095, 0 mod 8
        C_UAUTO4K_4  // 0 to 4095, 0 mod 4
        C_UAUTO4K_2  // 0 to 4095, 0 mod 2
@@ -319,7 +318,6 @@ const (
        C_NSOREG
        C_PSOREG_8
        C_PSOREG
-       C_PPOREG_8
        C_PPOREG
        C_UOREG4K_8
        C_UOREG4K_4

diff --git a/src/cmd/internal/obj/arm64/anames7.go b/src/cmd/internal/obj/arm64/anames7.go
index 6ad9d58132d9a533409973c5671865a0c494dbbd..a9cccc19f6db1de5e230fae83784575d2c19982a 100644 (file)
--- a/src/cmd/internal/obj/arm64/anames7.go
+++ b/src/cmd/internal/obj/arm64/anames7.go
@@ -37,7 +37,6 @@ var cnames7 = []string{
        "NSAUTO",
        "PSAUTO_8",
        "PSAUTO",
-       "PPAUTO_8",
        "PPAUTO",
        "UAUTO4K_8",
        "UAUTO4K_4",
@@ -61,7 +60,6 @@ var cnames7 = []string{
        "NSOREG",
        "PSOREG_8",
        "PSOREG",
-       "PPOREG_8",
        "PPOREG",
        "UOREG4K_8",
        "UOREG4K_4",

diff --git a/src/cmd/internal/obj/arm64/asm7.go b/src/cmd/internal/obj/arm64/asm7.go
index 10f0303785c261119b6c50f5665b9737ffcfaac5..b5bc858d7e21cd39c50f153c933323e12bfb7676 100644 (file)
--- a/src/cmd/internal/obj/arm64/asm7.go
+++ b/src/cmd/internal/obj/arm64/asm7.go
@@ -432,9 +432,9 @@ var optab = []Optab{
        {ALDP, C_NPAUTO, C_NONE, C_PAIR, 66, 4, REGSP, 0, 0},
        {ALDP, C_NPAUTO, C_NONE, C_PAIR, 66, 4, REGSP, 0, C_XPRE},
        {ALDP, C_NPAUTO, C_NONE, C_PAIR, 66, 4, REGSP, 0, C_XPOST},
-       {ALDP, C_PPAUTO_8, C_NONE, C_PAIR, 66, 4, REGSP, 0, 0},
-       {ALDP, C_PPAUTO_8, C_NONE, C_PAIR, 66, 4, REGSP, 0, C_XPRE},
-       {ALDP, C_PPAUTO_8, C_NONE, C_PAIR, 66, 4, REGSP, 0, C_XPOST},
+       {ALDP, C_PPAUTO, C_NONE, C_PAIR, 66, 4, REGSP, 0, 0},
+       {ALDP, C_PPAUTO, C_NONE, C_PAIR, 66, 4, REGSP, 0, C_XPRE},
+       {ALDP, C_PPAUTO, C_NONE, C_PAIR, 66, 4, REGSP, 0, C_XPOST},
        {ALDP, C_UAUTO4K, C_NONE, C_PAIR, 74, 8, REGSP, 0, 0},
        {ALDP, C_UAUTO4K, C_NONE, C_PAIR, 74, 8, REGSP, 0, C_XPRE},
        {ALDP, C_UAUTO4K, C_NONE, C_PAIR, 74, 8, REGSP, 0, C_XPOST},
@@ -444,9 +444,9 @@ var optab = []Optab{
        {ALDP, C_NPOREG, C_NONE, C_PAIR, 66, 4, 0, 0, 0},
        {ALDP, C_NPOREG, C_NONE, C_PAIR, 66, 4, 0, 0, C_XPRE},
        {ALDP, C_NPOREG, C_NONE, C_PAIR, 66, 4, 0, 0, C_XPOST},
-       {ALDP, C_PPOREG_8, C_NONE, C_PAIR, 66, 4, 0, 0, 0},
-       {ALDP, C_PPOREG_8, C_NONE, C_PAIR, 66, 4, 0, 0, C_XPRE},
-       {ALDP, C_PPOREG_8, C_NONE, C_PAIR, 66, 4, 0, 0, C_XPOST},
+       {ALDP, C_PPOREG, C_NONE, C_PAIR, 66, 4, 0, 0, 0},
+       {ALDP, C_PPOREG, C_NONE, C_PAIR, 66, 4, 0, 0, C_XPRE},
+       {ALDP, C_PPOREG, C_NONE, C_PAIR, 66, 4, 0, 0, C_XPOST},
        {ALDP, C_UOREG4K, C_NONE, C_PAIR, 74, 8, 0, 0, 0},
        {ALDP, C_UOREG4K, C_NONE, C_PAIR, 74, 8, 0, 0, C_XPRE},
        {ALDP, C_UOREG4K, C_NONE, C_PAIR, 74, 8, 0, 0, C_XPOST},
@@ -457,9 +457,9 @@ var optab = []Optab{
        {ASTP, C_PAIR, C_NONE, C_NPAUTO, 67, 4, REGSP, 0, 0},
        {ASTP, C_PAIR, C_NONE, C_NPAUTO, 67, 4, REGSP, 0, C_XPRE},
        {ASTP, C_PAIR, C_NONE, C_NPAUTO, 67, 4, REGSP, 0, C_XPOST},
-       {ASTP, C_PAIR, C_NONE, C_PPAUTO_8, 67, 4, REGSP, 0, 0},
-       {ASTP, C_PAIR, C_NONE, C_PPAUTO_8, 67, 4, REGSP, 0, C_XPRE},
-       {ASTP, C_PAIR, C_NONE, C_PPAUTO_8, 67, 4, REGSP, 0, C_XPOST},
+       {ASTP, C_PAIR, C_NONE, C_PPAUTO, 67, 4, REGSP, 0, 0},
+       {ASTP, C_PAIR, C_NONE, C_PPAUTO, 67, 4, REGSP, 0, C_XPRE},
+       {ASTP, C_PAIR, C_NONE, C_PPAUTO, 67, 4, REGSP, 0, C_XPOST},
        {ASTP, C_PAIR, C_NONE, C_UAUTO4K, 76, 8, REGSP, 0, 0},
        {ASTP, C_PAIR, C_NONE, C_UAUTO4K, 76, 8, REGSP, 0, C_XPRE},
        {ASTP, C_PAIR, C_NONE, C_UAUTO4K, 76, 8, REGSP, 0, C_XPOST},
@@ -469,9 +469,9 @@ var optab = []Optab{
        {ASTP, C_PAIR, C_NONE, C_NPOREG, 67, 4, 0, 0, 0},
        {ASTP, C_PAIR, C_NONE, C_NPOREG, 67, 4, 0, 0, C_XPRE},
        {ASTP, C_PAIR, C_NONE, C_NPOREG, 67, 4, 0, 0, C_XPOST},
-       {ASTP, C_PAIR, C_NONE, C_PPOREG_8, 67, 4, 0, 0, 0},
-       {ASTP, C_PAIR, C_NONE, C_PPOREG_8, 67, 4, 0, 0, C_XPRE},
-       {ASTP, C_PAIR, C_NONE, C_PPOREG_8, 67, 4, 0, 0, C_XPOST},
+       {ASTP, C_PAIR, C_NONE, C_PPOREG, 67, 4, 0, 0, 0},
+       {ASTP, C_PAIR, C_NONE, C_PPOREG, 67, 4, 0, 0, C_XPRE},
+       {ASTP, C_PAIR, C_NONE, C_PPOREG, 67, 4, 0, 0, C_XPOST},
        {ASTP, C_PAIR, C_NONE, C_UOREG4K, 76, 8, 0, 0, 0},
        {ASTP, C_PAIR, C_NONE, C_UOREG4K, 76, 8, 0, 0, C_XPRE},
        {ASTP, C_PAIR, C_NONE, C_UOREG4K, 76, 8, 0, 0, C_XPOST},
@@ -808,7 +808,6 @@ func (c *ctxt7) addpool(p *obj.Prog, a *obj.Addr) {
        case C_PSAUTO,
                C_PSAUTO_8,
                C_PPAUTO,
-               C_PPAUTO_8,
                C_UAUTO4K_8,
                C_UAUTO4K_4,
                C_UAUTO4K_2,
@@ -823,7 +822,6 @@ func (c *ctxt7) addpool(p *obj.Prog, a *obj.Addr) {
                C_NPAUTO,
                C_LAUTO,
                C_PPOREG,
-               C_PPOREG_8,
                C_PSOREG,
                C_PSOREG_8,
                C_UOREG4K_8,
@@ -1051,10 +1049,7 @@ func autoclass(l int64) int {
                }
                return C_PSAUTO
        }
-       if l <= 504 {
-               if (l & 7) == 0 {
-                       return C_PPAUTO_8
-               }
+       if l <= 504 && l&7 == 0 {
                return C_PPAUTO
        }
        if l <= 4095 {
@@ -1457,36 +1452,31 @@ func cmp(a int, b int) bool {
                }
 
        case C_PPAUTO:
-               if b == C_PSAUTO || b == C_PSAUTO_8 {
-                       return true
-               }
-
-       case C_PPAUTO_8:
                if b == C_PSAUTO_8 {
                        return true
                }
 
        case C_UAUTO4K:
                switch b {
-               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_PPAUTO_8, C_UAUTO4K_2, C_UAUTO4K_4, C_UAUTO4K_8:
+               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_UAUTO4K_2, C_UAUTO4K_4, C_UAUTO4K_8:
                        return true
                }
 
        case C_UAUTO8K:
                switch b {
-               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_PPAUTO_8, C_UAUTO4K_2, C_UAUTO4K_4, C_UAUTO4K_8, C_UAUTO8K_4, C_UAUTO8K_8:
+               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_UAUTO4K_2, C_UAUTO4K_4, C_UAUTO4K_8, C_UAUTO8K_4, C_UAUTO8K_8:
                        return true
                }
 
        case C_UAUTO16K:
                switch b {
-               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_PPAUTO_8, C_UAUTO4K_4, C_UAUTO4K_8, C_UAUTO8K_4, C_UAUTO8K_8, C_UAUTO16K_8:
+               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_UAUTO4K_4, C_UAUTO4K_8, C_UAUTO8K_4, C_UAUTO8K_8, C_UAUTO16K_8:
                        return true
                }
 
        case C_UAUTO32K:
                switch b {
-               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_PPAUTO_8, C_UAUTO4K_8, C_UAUTO8K_8, C_UAUTO16K_8:
+               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_UAUTO4K_8, C_UAUTO8K_8, C_UAUTO16K_8:
                        return true
                }
 
@@ -1495,7 +1485,7 @@ func cmp(a int, b int) bool {
 
        case C_LAUTO:
                switch b {
-               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO, C_PPAUTO_8,
+               case C_PSAUTO, C_PSAUTO_8, C_PPAUTO,
                        C_UAUTO4K, C_UAUTO4K_2, C_UAUTO4K_4, C_UAUTO4K_8,
                        C_UAUTO8K, C_UAUTO8K_4, C_UAUTO8K_8,
                        C_UAUTO16K, C_UAUTO16K_8,
@@ -1511,36 +1501,31 @@ func cmp(a int, b int) bool {
 
        case C_PPOREG:
                switch b {
-               case C_ZOREG, C_PSOREG, C_PSOREG_8, C_PPOREG_8:
-                       return true
-               }
-
-       case C_PPOREG_8:
-               if b == C_ZOREG || b == C_PSOREG_8 {
+               case C_ZOREG, C_PSOREG_8:
                        return true
                }
 
        case C_UOREG4K:
                switch b {
-               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG_8, C_PPOREG, C_UOREG4K_2, C_UOREG4K_4, C_UOREG4K_8:
+               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG, C_UOREG4K_2, C_UOREG4K_4, C_UOREG4K_8:
                        return true
                }
 
        case C_UOREG8K:
                switch b {
-               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG_8, C_PPOREG, C_UOREG4K_2, C_UOREG4K_4, C_UOREG4K_8, C_UOREG8K_4, C_UOREG8K_8:
+               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG, C_UOREG4K_2, C_UOREG4K_4, C_UOREG4K_8, C_UOREG8K_4, C_UOREG8K_8:
                        return true
                }
 
        case C_UOREG16K:
                switch b {
-               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG_8, C_PPOREG, C_UOREG4K_4, C_UOREG4K_8, C_UOREG8K_4, C_UOREG8K_8, C_UOREG16K_8:
+               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG, C_UOREG4K_4, C_UOREG4K_8, C_UOREG8K_4, C_UOREG8K_8, C_UOREG16K_8:
                        return true
                }
 
        case C_UOREG32K:
                switch b {
-               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG_8, C_PPOREG, C_UOREG4K_8, C_UOREG8K_8, C_UOREG16K_8:
+               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG, C_UOREG4K_8, C_UOREG8K_8, C_UOREG16K_8:
                        return true
                }
 
@@ -1549,7 +1534,7 @@ func cmp(a int, b int) bool {
 
        case C_LOREG:
                switch b {
-               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG_8, C_PPOREG,
+               case C_ZOREG, C_PSOREG_8, C_PSOREG, C_PPOREG,
                        C_UOREG4K, C_UOREG4K_2, C_UOREG4K_4, C_UOREG4K_8,
                        C_UOREG8K, C_UOREG8K_4, C_UOREG8K_8,
                        C_UOREG16K, C_UOREG16K_8,

diff --git a/test/fixedbugs/issue19137.go b/test/fixedbugs/issue19137.go
index 946f029be11e5602db3b1604df4a7df8aef27b28..0539a850ca69cba4c45ab469abc9cdedd8c5c002 100644 (file)
--- a/test/fixedbugs/issue19137.go
+++ b/test/fixedbugs/issue19137.go
@@ -33,3 +33,19 @@ func zero() ([20]byte, [20]byte) {
        _ = x
        return [20]byte{}, [20]byte{} // the second return value is not 8-byte aligned to SP
 }
+
+// Issue 21992: unaligned offset between 256 and 504 and handled
+// incorrectly.
+type T2 struct {
+       a [257]byte
+       // fields below are not 8-, 4-, 2-byte aligned
+       b [8]byte
+       c [4]byte
+       d [2]byte
+}
+
+func f2(x *T2) {
+       x.b = [8]byte{}
+       x.c = [4]byte{}
+       x.d = [2]byte{}
+}