cmd/internal/obj: stop removing NOPs from instruction stream
This has already been done for s390x, ppc64. This CL is for
all the other architectures.
Fixes #40796
Change-Id: Idd1816e057df63022d47e99fa06617811d8c8489
Reviewed-on: https://go-review.googlesource.com/c/go/+/248684
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
diff --git a/src/cmd/internal/obj/arm/asm5.go b/src/cmd/internal/obj/arm/asm5.go
index f66f8aa..7b7e42e 100644
--- a/src/cmd/internal/obj/arm/asm5.go
+++ b/src/cmd/internal/obj/arm/asm5.go
@@ -327,6 +327,9 @@
{obj.APCDATA, C_LCON, C_NONE, C_LCON, 0, 0, 0, 0, 0, 0},
{obj.AFUNCDATA, C_LCON, C_NONE, C_ADDR, 0, 0, 0, 0, 0, 0},
{obj.ANOP, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0, 0},
+ {obj.ANOP, C_LCON, C_NONE, C_NONE, 0, 0, 0, 0, 0, 0}, // nop variants, see #40689
+ {obj.ANOP, C_REG, C_NONE, C_NONE, 0, 0, 0, 0, 0, 0},
+ {obj.ANOP, C_FREG, C_NONE, C_NONE, 0, 0, 0, 0, 0, 0},
{obj.ADUFFZERO, C_NONE, C_NONE, C_SBRA, 5, 4, 0, 0, 0, 0}, // same as ABL
{obj.ADUFFCOPY, C_NONE, C_NONE, C_SBRA, 5, 4, 0, 0, 0, 0}, // same as ABL
{obj.AXXX, C_NONE, C_NONE, C_NONE, 0, 4, 0, 0, 0, 0},
diff --git a/src/cmd/internal/obj/arm/obj5.go b/src/cmd/internal/obj/arm/obj5.go
index 008118c..86831f2 100644
--- a/src/cmd/internal/obj/arm/obj5.go
+++ b/src/cmd/internal/obj/arm/obj5.go
@@ -276,67 +276,21 @@
/*
* find leaf subroutines
- * strip NOPs
- * expand RET
- * expand BECOME pseudo
*/
- var q1 *obj.Prog
- var q *obj.Prog
for p := cursym.Func.Text; p != nil; p = p.Link {
switch p.As {
case obj.ATEXT:
p.Mark |= LEAF
- case obj.ARET:
- break
-
case ADIV, ADIVU, AMOD, AMODU:
- q = p
cursym.Func.Text.Mark &^= LEAF
- continue
-
- case obj.ANOP:
- q1 = p.Link
- q.Link = q1 /* q is non-nop */
- if q1 != nil {
- q1.Mark |= p.Mark
- }
- continue
case ABL,
ABX,
obj.ADUFFZERO,
obj.ADUFFCOPY:
cursym.Func.Text.Mark &^= LEAF
- fallthrough
-
- case AB,
- ABEQ,
- ABNE,
- ABCS,
- ABHS,
- ABCC,
- ABLO,
- ABMI,
- ABPL,
- ABVS,
- ABVC,
- ABHI,
- ABLS,
- ABGE,
- ABLT,
- ABGT,
- ABLE:
- q1 = p.Pcond
- if q1 != nil {
- for q1.As == obj.ANOP {
- q1 = q1.Link
- p.Pcond = q1
- }
- }
}
-
- q = p
}
var q2 *obj.Prog
diff --git a/src/cmd/internal/obj/arm64/asm7.go b/src/cmd/internal/obj/arm64/asm7.go
index 8f89814..7a5a8ff 100644
--- a/src/cmd/internal/obj/arm64/asm7.go
+++ b/src/cmd/internal/obj/arm64/asm7.go
@@ -837,6 +837,9 @@
{obj.APCDATA, C_VCON, C_NONE, C_NONE, C_VCON, 0, 0, 0, 0, 0},
{obj.AFUNCDATA, C_VCON, C_NONE, C_NONE, C_ADDR, 0, 0, 0, 0, 0},
{obj.ANOP, C_NONE, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0},
+ {obj.ANOP, C_LCON, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0}, // nop variants, see #40689
+ {obj.ANOP, C_REG, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0},
+ {obj.ANOP, C_VREG, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0},
{obj.ADUFFZERO, C_NONE, C_NONE, C_NONE, C_SBRA, 5, 4, 0, 0, 0}, // same as AB/ABL
{obj.ADUFFCOPY, C_NONE, C_NONE, C_NONE, C_SBRA, 5, 4, 0, 0, 0}, // same as AB/ABL
{obj.APCALIGN, C_LCON, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0}, // align code
diff --git a/src/cmd/internal/obj/arm64/obj7.go b/src/cmd/internal/obj/arm64/obj7.go
index b046685..0d74430 100644
--- a/src/cmd/internal/obj/arm64/obj7.go
+++ b/src/cmd/internal/obj/arm64/obj7.go
@@ -468,73 +468,21 @@
/*
* find leaf subroutines
- * strip NOPs
- * expand RET
*/
- q := (*obj.Prog)(nil)
- var q1 *obj.Prog
for p := c.cursym.Func.Text; p != nil; p = p.Link {
switch p.As {
case obj.ATEXT:
p.Mark |= LEAF
- case obj.ARET:
- break
-
- case obj.ANOP:
- if p.Link != nil {
- q1 = p.Link
- q.Link = q1 /* q is non-nop */
- q1.Mark |= p.Mark
- }
- continue
-
case ABL,
obj.ADUFFZERO,
obj.ADUFFCOPY:
c.cursym.Func.Text.Mark &^= LEAF
- fallthrough
-
- case ACBNZ,
- ACBZ,
- ACBNZW,
- ACBZW,
- ATBZ,
- ATBNZ,
- AB,
- ABEQ,
- ABNE,
- ABCS,
- ABHS,
- ABCC,
- ABLO,
- ABMI,
- ABPL,
- ABVS,
- ABVC,
- ABHI,
- ABLS,
- ABGE,
- ABLT,
- ABGT,
- ABLE,
- AADR, /* strange */
- AADRP:
- q1 = p.Pcond
-
- if q1 != nil {
- for q1.As == obj.ANOP {
- q1 = q1.Link
- p.Pcond = q1
- }
- }
-
- break
}
-
- q = p
}
+ var q *obj.Prog
+ var q1 *obj.Prog
var retjmp *obj.LSym
for p := c.cursym.Func.Text; p != nil; p = p.Link {
o := p.As
diff --git a/src/cmd/internal/obj/mips/asm0.go b/src/cmd/internal/obj/mips/asm0.go
index faa12bf..faa827d 100644
--- a/src/cmd/internal/obj/mips/asm0.go
+++ b/src/cmd/internal/obj/mips/asm0.go
@@ -391,6 +391,9 @@
{obj.APCDATA, C_LCON, C_NONE, C_LCON, 0, 0, 0, 0, 0},
{obj.AFUNCDATA, C_SCON, C_NONE, C_ADDR, 0, 0, 0, 0, 0},
{obj.ANOP, C_NONE, C_NONE, C_NONE, 0, 0, 0, 0, 0},
+ {obj.ANOP, C_LCON, C_NONE, C_NONE, 0, 0, 0, 0, 0}, // nop variants, see #40689
+ {obj.ANOP, C_REG, C_NONE, C_NONE, 0, 0, 0, 0, 0},
+ {obj.ANOP, C_FREG, C_NONE, C_NONE, 0, 0, 0, 0, 0},
{obj.ADUFFZERO, C_NONE, C_NONE, C_LBRA, 11, 4, 0, 0, 0}, // same as AJMP
{obj.ADUFFCOPY, C_NONE, C_NONE, C_LBRA, 11, 4, 0, 0, 0}, // same as AJMP
diff --git a/src/cmd/internal/obj/mips/obj0.go b/src/cmd/internal/obj/mips/obj0.go
index 3106143..77cad97 100644
--- a/src/cmd/internal/obj/mips/obj0.go
+++ b/src/cmd/internal/obj/mips/obj0.go
@@ -158,19 +158,14 @@
/*
* find leaf subroutines
- * strip NOPs
* expand RET
* expand BECOME pseudo
*/
- var q *obj.Prog
- var q1 *obj.Prog
for p := c.cursym.Func.Text; p != nil; p = p.Link {
switch p.As {
/* too hard, just leave alone */
case obj.ATEXT:
- q = p
-
p.Mark |= LABEL | LEAF | SYNC
if p.Link != nil {
p.Link.Mark |= LABEL
@@ -179,7 +174,6 @@
/* too hard, just leave alone */
case AMOVW,
AMOVV:
- q = p
if p.To.Type == obj.TYPE_REG && p.To.Reg >= REG_SPECIAL {
p.Mark |= LABEL | SYNC
break
@@ -195,11 +189,9 @@
ATLBWI,
ATLBP,
ATLBR:
- q = p
p.Mark |= LABEL | SYNC
case ANOR:
- q = p
if p.To.Type == obj.TYPE_REG {
if p.To.Reg == REGZERO {
p.Mark |= LABEL | SYNC
@@ -235,8 +227,7 @@
} else {
p.Mark |= BRANCH
}
- q = p
- q1 = p.Pcond
+ q1 := p.Pcond
if q1 != nil {
for q1.As == obj.ANOP {
q1 = q1.Link
@@ -254,24 +245,11 @@
if q1 != nil {
q1.Mark |= LABEL
}
- continue
case ARET:
- q = p
if p.Link != nil {
p.Link.Mark |= LABEL
}
- continue
-
- case obj.ANOP:
- q1 = p.Link
- q.Link = q1 /* q is non-nop */
- q1.Mark |= p.Mark
- continue
-
- default:
- q = p
- continue
}
}
@@ -284,6 +262,8 @@
mov = AMOVW
}
+ var q *obj.Prog
+ var q1 *obj.Prog
autosize := int32(0)
var p1 *obj.Prog
var p2 *obj.Prog
