gas: change meaning of ; in the BPF assembler

The BPF assembler in clang uses semi-colon (;) to separate statements,
not to be begin line comments.  This patch adapts the GNU assembler
accordingly.

Testsuite and documentation updated accordingly.

2023-11-28  Jose E. Marchesi  <jose.marchesi@oracle.com>

	* config/tc-bpf.c: Semicolon does not start a comment, but
	separates multiple commands on a single line.
	* testsuite/gas/bpf/alu-pseudoc.s: Adapt test accordingly.
	* testsuite/gas/bpf/spacing-pseudoc.s: Likewise.
	* testsuite/gas/bpf/offset16-overflow.s: Likewise.
	* testsuite/gas/bpf/jump-relax-jump.s: Likewise.
	* testsuite/gas/bpf/jump-relax-ja.s: Likewise.
	* testsuite/gas/bpf/imm32-overflow.s: Likewise.
	* testsuite/gas/bpf/disp32-overflow.s: Likewise.
	* testsuite/gas/bpf/disp16-overflow-relax.s: Likewise.
	* testsuite/gas/bpf/disp16-overflow.s: Likewise.
	* doc/c-bpf.texi (BPF Special Characters): Update.

12 files changed, 57 insertions, 35 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 9414f7d..c5e781d 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,18 @@
+2023-11-28  Jose E. Marchesi  <jose.marchesi@oracle.com>
+
+	* config/tc-bpf.c: Semicolon does not start a comment, but
+	separates multiple commands on a single line.
+	* testsuite/gas/bpf/alu-pseudoc.s: Adapt test accordingly.
+	* testsuite/gas/bpf/spacing-pseudoc.s: Likewise.
+	* testsuite/gas/bpf/offset16-overflow.s: Likewise.
+	* testsuite/gas/bpf/jump-relax-jump.s: Likewise.
+	* testsuite/gas/bpf/jump-relax-ja.s: Likewise.
+	* testsuite/gas/bpf/imm32-overflow.s: Likewise.
+	* testsuite/gas/bpf/disp32-overflow.s: Likewise.
+	* testsuite/gas/bpf/disp16-overflow-relax.s: Likewise.
+	* testsuite/gas/bpf/disp16-overflow.s: Likewise.
+	* doc/c-bpf.texi (BPF Special Characters): Update.
+
 2023-11-23  YunQiang Su  <yunqiang.su@cipunited.com>
 
 	* testsuite/gas/mips/elf-rel.s: Use addiu in place of addi.
diff --git a/gas/config/tc-bpf.c b/gas/config/tc-bpf.c
index b6b1db4..0056754 100644
--- a/gas/config/tc-bpf.c
+++ b/gas/config/tc-bpf.c
@@ -56,9 +56,9 @@ struct bpf_insn
   expressionS *relaxed_exp;
 };
 
-const char comment_chars[]        = ";#";
+const char comment_chars[]        = "#";
 const char line_comment_chars[]   = "#";
-const char line_separator_chars[] = "`";
+const char line_separator_chars[] = ";`";
 const char EXP_CHARS[]            = "eE";
 const char FLT_CHARS[]            = "fFdD";
 
diff --git a/gas/doc/c-bpf.texi b/gas/doc/c-bpf.texi
index 25ae231..7ff07e9 100644
--- a/gas/doc/c-bpf.texi
+++ b/gas/doc/c-bpf.texi
@@ -68,11 +68,18 @@ the host endianness is used.
 
 @cindex line comment character, BPF
 @cindex BPF line comment character
-The presence of a @samp{;} or a @samp{#} on a line indicates the start
-of a comment that extends to the end of the current line.
+The presence of a @samp{#} on a line indicates the start of a comment
+that extends to the end of the current line.
+
+@cindex block comments, BPF
+@cindex BPF block comments
+The presence of the @samp{/*} sequence indicates the beginning of a
+block (multi-line) comment, whose contents span until the next
+@samp{*/} sequence.  It is not possible to nest block comments.
 
 @cindex statement separator, BPF
-Statements and assembly directives are separated by newlines.
+Statements and assembly directives are separated by newlines and
+@samp{;} characters.
 
 @node BPF Registers
 @section BPF Registers
diff --git a/gas/testsuite/gas/bpf/alu-pseudoc.s b/gas/testsuite/gas/bpf/alu-pseudoc.s
index 3d60d4f..04d2b76 100644
--- a/gas/testsuite/gas/bpf/alu-pseudoc.s
+++ b/gas/testsuite/gas/bpf/alu-pseudoc.s
@@ -61,5 +61,5 @@
         r1 = bswap16 r1
         r2 = bswap32 r2
         r3 = bswap64 r3
-        ;; The following is to be interpreted as a mov, not lddw.
+        /* The following is to be interpreted as a mov, not lddw. */
         r2 = 666ll
diff --git a/gas/testsuite/gas/bpf/disp16-overflow-relax.s b/gas/testsuite/gas/bpf/disp16-overflow-relax.s
index 05d505c..7ac969a 100644
--- a/gas/testsuite/gas/bpf/disp16-overflow-relax.s
+++ b/gas/testsuite/gas/bpf/disp16-overflow-relax.s
@@ -1,4 +1,4 @@
-        jeq %r1,%r2,2147483647  ; Overflows.
-        jlt %r3,%r4,2147483648  ; Overflows.
-        jge %r5,10,-2147483648  ; Overflows.
-        ja -2147483649          ; Overflows.
+        jeq %r1,%r2,2147483647  /* Overflows. */
+        jlt %r3,%r4,2147483648  /* Overflows. */
+        jge %r5,10,-2147483648  /* Overflows. */
+        ja -2147483649          /* Overflows. */
diff --git a/gas/testsuite/gas/bpf/disp16-overflow.s b/gas/testsuite/gas/bpf/disp16-overflow.s
index 4a8fd9f..c46590e 100644
--- a/gas/testsuite/gas/bpf/disp16-overflow.s
+++ b/gas/testsuite/gas/bpf/disp16-overflow.s
@@ -1,4 +1,4 @@
         ja 32767
-        jeq %r1,%r2,65536       ; Overflows
+        jeq %r1,%r2,65536       /* Overflows */
         jlt %r3,%r4,-32768
-        jge %r5,10,-32769       ; Overflows
+        jge %r5,10,-32769       /* Overflows */
diff --git a/gas/testsuite/gas/bpf/disp32-overflow.s b/gas/testsuite/gas/bpf/disp32-overflow.s
index 11128a2..eb8b445 100644
--- a/gas/testsuite/gas/bpf/disp32-overflow.s
+++ b/gas/testsuite/gas/bpf/disp32-overflow.s
@@ -1,4 +1,4 @@
         call -2147483648
-        call -2147483649        ; This overflows.
+        call -2147483649        /* This overflows.  */
         call 4294967295
-        call 4294967296         ; This overflows.
+        call 4294967296         /* This overflows.  */
diff --git a/gas/testsuite/gas/bpf/imm32-overflow.s b/gas/testsuite/gas/bpf/imm32-overflow.s
index b2ab43d..1aac58b 100644
--- a/gas/testsuite/gas/bpf/imm32-overflow.s
+++ b/gas/testsuite/gas/bpf/imm32-overflow.s
@@ -1,4 +1,4 @@
         add %r1, 2147483647
-        or %r2, 4294967296         ; This overflows.
+        or %r2, 4294967296         /* This overflows.  */
         xor %r3, 4294967295
-        sub %r4, 4294967296        ; This overflows.
+        sub %r4, 4294967296        /* This overflows.  */
diff --git a/gas/testsuite/gas/bpf/jump-relax-ja.s b/gas/testsuite/gas/bpf/jump-relax-ja.s
index 1faf679..f164176 100644
--- a/gas/testsuite/gas/bpf/jump-relax-ja.s
+++ b/gas/testsuite/gas/bpf/jump-relax-ja.s
@@ -1,16 +1,16 @@
-        ;; The following two instructions have constant targets that
-        ;; fix in the JA 16-bit signed displacement operand.  These
-        ;; are not relaxed.
+        /* The following two instructions have constant targets that
+           fix in the JA 16-bit signed displacement operand.  These
+           are not relaxed.  */
 1:      ja -32768
         ja 32767
-        ;; The following instruction refers to a defined symbol that
-        ;; is on reach, so it should not be relaxed.
+        /* The following instruction refers to a defined symbol that
+           is on reach, so it should not be relaxed.  */
         ja 1b
-        ;; The following instruction has an undefined symbol as a
-        ;; target.  It is not to be relaxed.
+        /* The following instruction has an undefined symbol as a
+           target.  It is not to be relaxed.  */
         ja undefined + 10
-        ;; The following instructions refer to a defined symbol that
-        ;; is not on reach.  They shall be relaxed to a JAL.
+        /* The following instructions refer to a defined symbol that
+           is not on reach.  They shall be relaxed to a JAL.  */
         ja tail
         tail = .text + 262160
         ja tail
diff --git a/gas/testsuite/gas/bpf/jump-relax-jump.s b/gas/testsuite/gas/bpf/jump-relax-jump.s
index 3ee7c87..5ea6110 100644
--- a/gas/testsuite/gas/bpf/jump-relax-jump.s
+++ b/gas/testsuite/gas/bpf/jump-relax-jump.s
@@ -1,12 +1,12 @@
-        ;; The following two instructions have constant targets that
-        ;; fix in the jump 16-bit signed displacement operand.
+        /* The following two instructions have constant targets that
+           fix in the jump 16-bit signed displacement operand.  */
 1:      jeq %r1, %r2, -32768
         jlt %r1, %r2, 32767
-        ;; The following instruction refers to a defined symbol that
-        ;; is on reach, so it should not be relaxed.
+        /* The following instruction refers to a defined symbol that
+           is on reach, so it should not be relaxed.  */
         jle %r1, %r2, 1b
-        ;; The following instructions refer to a defined symbol that
-        ;; is not on reach.  They shall be relaxed.
+        /* The following instructions refer to a defined symbol that
+           is not on reach.  They shall be relaxed.  */
         jeq %r1, %r2, tail
         tail = .text + 262160
         jgt %r1, %r2, tail
diff --git a/gas/testsuite/gas/bpf/offset16-overflow.s b/gas/testsuite/gas/bpf/offset16-overflow.s
index ebd8e05..2bcb63b 100644
--- a/gas/testsuite/gas/bpf/offset16-overflow.s
+++ b/gas/testsuite/gas/bpf/offset16-overflow.s
@@ -1,4 +1,4 @@
         ldxh %r2, [%r1 + 65535]
-        ldxw %r2, [%r1 + 65536]  ; This overflows
+        ldxw %r2, [%r1 + 65536]  /* This overflows.  */
         stxw [%r2 - 32768], %r1
-        stxdw [%r2 - 32769], %r1  ; This overflows
+        stxdw [%r2 - 32769], %r1  /* This overflows.  */
diff --git a/gas/testsuite/gas/bpf/spacing-pseudoc.s b/gas/testsuite/gas/bpf/spacing-pseudoc.s
index 3c19d9a..5aff93d 100644
--- a/gas/testsuite/gas/bpf/spacing-pseudoc.s
+++ b/gas/testsuite/gas/bpf/spacing-pseudoc.s
@@ -1,5 +1,5 @@
-        ;; This test checks that flexible spacing is supported in the
-        ;; pseudoc syntax.
+        /* This test checks that flexible spacing is supported in the
+           pseudoc syntax.  */
         r4 = 0xdeadbeefll
         r4 = 0xdeadbeef ll
         goto +1