cmd/internal/obj/ppc64: combine C_SBRA and C_LBRA optab classes

The assembler treats C_SBRA and C_LBRA optab classes identically,
combine them into one class to reduce the number of optab classes.

Likewise, C_LBRAPIC is renamed to C_BRAPIC for consistency with
the above change.

Change-Id: I47000e7273cb8f89a4d0621d71433ccbfb7afb70
Reviewed-on: https://go-review.googlesource.com/c/go/+/557916
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>

src/cmd/internal/obj/ppc64/a.out.go

@@ -428,9 +428,8 @@ const (
 	C_SACON    /* $n(REG) where n <= int16 */
 	C_LACON    /* $n(REG) where n <= int32 */
 	C_DACON    /* $n(REG) where n <= int64 */
-	C_SBRA     /* A short offset argument to a branching instruction */
+	C_BRA      /* A short offset argument to a branching instruction */
-	C_LBRA     /* A long offset argument to a branching instruction */
+	C_BRAPIC   /* Like C_BRA, but requires an extra NOP for potential TOC restore by the linker. */
-	C_LBRAPIC  /* Like C_LBRA, but requires an extra NOP for potential TOC restore by the linker. */
 	C_ZOREG    /* An $0+reg memory op */
 	C_SOREG    /* An $n+reg memory arg where n is a 16 bit signed offset */
 	C_LOREG    /* An $n+reg memory arg where n is a 32 bit signed offset */

src/cmd/internal/obj/ppc64/anames9.go

@@ -33,9 +33,8 @@ var cnames9 = []string{
 	"SACON",
 	"LACON",
 	"DACON",
-	"SBRA",
+	"BRA",
-	"LBRA",
+	"BRAPIC",
-	"LBRAPIC",
 	"ZOREG",
 	"SOREG",
 	"LOREG",

src/cmd/internal/obj/ppc64/asm9.go

@@ -284,18 +284,17 @@ var optabBase = []Optab{
 	{as: ASYSCALL, type_: 5, size: 4},
 	{as: ASYSCALL, a1: C_REG, type_: 77, size: 12},
 	{as: ASYSCALL, a1: C_SCON, type_: 77, size: 12},
-	{as: ABEQ, a6: C_SBRA, type_: 16, size: 4},
+	{as: ABEQ, a6: C_BRA, type_: 16, size: 4},
-	{as: ABEQ, a1: C_CREG, a6: C_SBRA, type_: 16, size: 4},
+	{as: ABEQ, a1: C_CREG, a6: C_BRA, type_: 16, size: 4},
-	{as: ABR, a6: C_LBRA, type_: 11, size: 4},                                    // b label
+	{as: ABR, a6: C_BRA, type_: 11, size: 4},                                     // b label
-	{as: ABR, a6: C_LBRAPIC, type_: 11, size: 8},                                 // b label; nop
+	{as: ABR, a6: C_BRAPIC, type_: 11, size: 8},                                  // b label; nop
 	{as: ABR, a6: C_LR, type_: 18, size: 4},                                      // blr
 	{as: ABR, a6: C_CTR, type_: 18, size: 4},                                     // bctr
-	{as: ABC, a1: C_SCON, a2: C_CRBIT, a6: C_SBRA, type_: 16, size: 4},           // bc bo, bi, label
+	{as: ABC, a1: C_SCON, a2: C_CRBIT, a6: C_BRA, type_: 16, size: 4},            // bc bo, bi, label
-	{as: ABC, a1: C_SCON, a2: C_CRBIT, a6: C_LBRA, type_: 17, size: 4},           // bc bo, bi, label
 	{as: ABC, a1: C_SCON, a2: C_CRBIT, a6: C_LR, type_: 18, size: 4},             // bclr bo, bi
 	{as: ABC, a1: C_SCON, a2: C_CRBIT, a3: C_SCON, a6: C_LR, type_: 18, size: 4}, // bclr bo, bi, bh
 	{as: ABC, a1: C_SCON, a2: C_CRBIT, a6: C_CTR, type_: 18, size: 4},            // bcctr bo, bi
-	{as: ABDNZ, a6: C_SBRA, type_: 16, size: 4},
+	{as: ABDNZ, a6: C_BRA, type_: 16, size: 4},
 	{as: ASYNC, type_: 46, size: 4},
 	{as: AWORD, a1: C_LCON, type_: 40, size: 4},
 	{as: ADWORD, a1: C_64CON, type_: 31, size: 8},
@@ -515,8 +514,8 @@ var optabBase = []Optab{
 	{as: obj.ANOP, a1: C_LCON, type_: 0, size: 0}, // NOP operand variations added for #40689
 	{as: obj.ANOP, a1: C_REG, type_: 0, size: 0},  // to preserve previous behavior
 	{as: obj.ANOP, a1: C_FREG, type_: 0, size: 0},
-	{as: obj.ADUFFZERO, a6: C_LBRA, type_: 11, size: 4}, // same as ABR/ABL
+	{as: obj.ADUFFZERO, a6: C_BRA, type_: 11, size: 4}, // same as ABR/ABL
-	{as: obj.ADUFFCOPY, a6: C_LBRA, type_: 11, size: 4}, // same as ABR/ABL
+	{as: obj.ADUFFCOPY, a6: C_BRA, type_: 11, size: 4}, // same as ABR/ABL
 	{as: obj.APCALIGN, a1: C_LCON, type_: 0, size: 0},  // align code
 }
 
@@ -1041,9 +1040,9 @@ func (c *ctxt9) aclass(a *obj.Addr) int {
 
 	case obj.TYPE_BRANCH:
 		if a.Sym != nil && c.ctxt.Flag_dynlink && !pfxEnabled {
-			return C_LBRAPIC
+			return C_BRAPIC
 		}
-		return C_SBRA
+		return C_BRA
 	}
 
 	return C_GOK
@@ -1160,9 +1159,6 @@ func cmp(a int, b int) bool {
 	case C_LACON:
 		return cmp(C_SACON, b)
 
-	case C_LBRA:
-		return cmp(C_SBRA, b)
-
 	case C_SOREG:
 		return cmp(C_ZOREG, b)
 
@@ -2654,7 +2650,7 @@ func asmout(c *ctxt9, p *obj.Prog, o *Optab, out *[5]uint32) {
 		}
 		o1 = AOP_RRR(c.oprrr(p.As), uint32(p.To.Reg), uint32(p.From.Reg), uint32(r))
 
-	case 11: /* br/bl lbra */
+	case 11: /* br/bl bra */
 		v := int32(0)
 
 		if p.To.Target() != nil {
@@ -2776,8 +2772,7 @@ func asmout(c *ctxt9, p *obj.Prog, o *Optab, out *[5]uint32) {
 			c.ctxt.Diag("unexpected op in rldc case\n%v", p)
 		}
 
-	case 17, /* bc bo,bi,lbra (same for now) */
+	case 16: /* bc bo,bi,bra */
-		16: /* bc bo,bi,sbra */
 		a := 0
 
 		r := int(p.Reg)

src/cmd/internal/obj/ppc64/asm_test.go

@@ -525,8 +525,8 @@ func TestAddrClassifier(t *testing.T) {
 		{obj.Addr{Type: obj.TYPE_CONST, Name: obj.NAME_NONE, Offset: -(1 << 34)}, C_64CON},
 
 		// Branch like arguments
-		{obj.Addr{Type: obj.TYPE_BRANCH, Sym: &obj.LSym{Type: objabi.SDATA}}, cmplx{C_SBRA, C_LBRAPIC, C_LBRAPIC, C_SBRA}},
+		{obj.Addr{Type: obj.TYPE_BRANCH, Sym: &obj.LSym{Type: objabi.SDATA}}, cmplx{C_BRA, C_BRAPIC, C_BRAPIC, C_BRA}},
-		{obj.Addr{Type: obj.TYPE_BRANCH}, C_SBRA},
+		{obj.Addr{Type: obj.TYPE_BRANCH}, C_BRA},
 	}
 
 	pic_ctxt9 := ctxt9{ctxt: &obj.Link{Flag_shared: true, Arch: &Linkppc64}, autosize: 0}