Re: [PATCH v2] bpf: pseudo-c assembly dialect support
> gcc/ChangeLog:
>
> * config/bpf/bpf.opt: Added option -masm=.
> * config/bpf/bpf-opts.h: Likewize.
> * config/bpf/bpf.cc: Changed it to conform with new pseudoc
> dialect support.
> * config/bpf/bpf.h: Likewise.
> * config/bpf/bpf.md: Added pseudo-c templates.
> * doc/invoke.texi: (-masm=DIALECT) New eBPF option item.
I think the ChangeLog could be made more useful, and the syntax of the
last entry is not entirely right. I suggest something like:
* config/bpf/bpf.opt: Added option -masm=.
* config/bpf/bpf-opts.h (enum bpf_asm_dialect): New type.
* config/bpf/bpf.cc (bpf_print_register): New function.
(bpf_print_register): Support pseudo-c syntax for registers.
(bpf_print_operand_address): Likewise.
* config/bpf/bpf.h (ASM_SPEC): handle -msasm.
(ASSEMBLER_DIALECT): Define.
* config/bpf/bpf.md: Added pseudo-c templates.
* doc/invoke.texi (-masm=DIALECT): New eBPF option item.
Please make sure to run the contrib/gcc-changelog/git_check-commit.py
script.
> ---
> gcc/config/bpf/bpf-opts.h | 6 +++
> gcc/config/bpf/bpf.cc | 46 ---
> gcc/config/bpf/bpf.h | 5 +-
> gcc/config/bpf/bpf.md | 97 ---
> gcc/config/bpf/bpf.opt| 14 ++
> gcc/doc/invoke.texi | 21 -
> 6 files changed, 133 insertions(+), 56 deletions(-)
>
> diff --git a/gcc/config/bpf/bpf-opts.h b/gcc/config/bpf/bpf-opts.h
> index 8282351cf045..92db01ec4d54 100644
> --- a/gcc/config/bpf/bpf-opts.h
> +++ b/gcc/config/bpf/bpf-opts.h
> @@ -60,4 +60,10 @@ enum bpf_isa_version
>ISA_V3,
> };
>
> +enum bpf_asm_dialect
> +{
> + ASM_NORMAL,
> + ASM_PSEUDOC
> +};
> +
> #endif /* ! BPF_OPTS_H */
> diff --git a/gcc/config/bpf/bpf.cc b/gcc/config/bpf/bpf.cc
> index e0324e1e0e08..1d3936871d60 100644
> --- a/gcc/config/bpf/bpf.cc
> +++ b/gcc/config/bpf/bpf.cc
> @@ -873,16 +873,47 @@ bpf_output_call (rtx target)
>return "";
> }
>
> +/* Print register name according to assembly dialect.
> + In normal syntax registers are printed like %rN where N is the
> + register number.
> + In pseudoc syntax, the register names do not feature a '%' prefix.
> + Additionally, the code 'w' denotes that the register should be printed
> + as wN instead of rN, where N is the register number, but only when the
> + value stored in the operand OP is 32-bit wide. */
> +static void
> +bpf_print_register (FILE *file, rtx op, int code)
> +{
> + if(asm_dialect == ASM_NORMAL)
> +fprintf (file, "%s", reg_names[REGNO (op)]);
> + else
> +{
> + if (code == 'w' && GET_MODE (op) == SImode)
> + {
> + if (REGNO (op) == BPF_FP)
> + fprintf (file, "w10");
> + else
> + fprintf (file, "w%s", reg_names[REGNO (op)]+2);
> + }
> + else
> + {
> + if (REGNO (op) == BPF_FP)
> + fprintf (file, "r10");
> + else
> + fprintf (file, "%s", reg_names[REGNO (op)]+1);
> + }
> +}
> +}
> +
> /* Print an instruction operand. This function is called in the macro
> PRINT_OPERAND defined in bpf.h */
>
> void
> -bpf_print_operand (FILE *file, rtx op, int code ATTRIBUTE_UNUSED)
> +bpf_print_operand (FILE *file, rtx op, int code)
> {
>switch (GET_CODE (op))
> {
> case REG:
> - fprintf (file, "%s", reg_names[REGNO (op)]);
> + bpf_print_register (file, op, code);
>break;
> case MEM:
>output_address (GET_MODE (op), XEXP (op, 0));
> @@ -936,7 +967,9 @@ bpf_print_operand_address (FILE *file, rtx addr)
>switch (GET_CODE (addr))
> {
> case REG:
> - fprintf (file, "[%s+0]", reg_names[REGNO (addr)]);
> + fprintf (file, asm_dialect == ASM_NORMAL ? "[" : "(");
> + bpf_print_register (file, addr, 0);
> + fprintf (file, asm_dialect == ASM_NORMAL ? "+0]" : "+0)");
>break;
> case PLUS:
>{
> @@ -945,9 +978,11 @@ bpf_print_operand_address (FILE *file, rtx addr)
>
> if (GET_CODE (op0) == REG && GET_CODE (op1) == CONST_INT)
> {
> - fprintf (file, "[%s+", reg_names[REGNO (op0)]);
> + fprintf (file, asm_dialect == ASM_NORMAL ? "[" : "(");
> + bpf_print_register (file, op0, 0);
> + fprintf (file, "+");
> output_addr_const (file, op1);
> - fputs ("]", file);
> + fprintf (file, asm_dialect == ASM_NORMAL ? "]" : ")");
> }
> else
> fatal_insn ("invalid address in operand", addr);
> @@ -1816,7 +1851,6 @@ handle_attr_preserve (function *fn)
> }
> }
>
> -
> /* This pass finds accesses to structures marked with the BPF target
> attribute
> __attribute__((preserve_access_index)). For every such access, a CO-RE
> relocation record is generated, to be output in the .BTF.ext section. */
> diff --git a/gcc/config/bpf/bpf.h b/gcc/config/bpf/bpf.h
> index 344aca02d1bb..9561bf59b800 100644
> --- a/gcc/config/bpf/bpf.h
Re: [PATCH v2] bpf: pseudo-c assembly dialect support
Hi Jose,
Thanks for the review.
New patch is inline attached.
Regards,
Cupertino
Jose E. Marchesi writes:
> Hello Cuper.
>
> Thanks for the patch.
>
> We will need an update for the "eBPF Options" section in the GCC manual,
> documenting -masm=@var{dialect} and the supported values. Can you
> please add it and re-submit?
>
>
>> Hi everyone,
>>
>> Looking forward to all your reviews.
>>
>> Best regards,
>> Cupertino
>From fa227fefd84e6eaaf8edafed698e9960d7b115e6 Mon Sep 17 00:00:00 2001
From: Cupertino Miranda
Date: Mon, 17 Jul 2023 17:42:42 +0100
Subject: [PATCH v2] bpf: pseudo-c assembly dialect support
New pseudo-c BPF assembly dialect already supported by clang and widely
used in the linux kernel.
gcc/ChangeLog:
* config/bpf/bpf.opt: Added option -masm=.
* config/bpf/bpf-opts.h: Likewize.
* config/bpf/bpf.cc: Changed it to conform with new pseudoc
dialect support.
* config/bpf/bpf.h: Likewise.
* config/bpf/bpf.md: Added pseudo-c templates.
* doc/invoke.texi: (-masm=DIALECT) New eBPF option item.
---
gcc/config/bpf/bpf-opts.h | 6 +++
gcc/config/bpf/bpf.cc | 46 ---
gcc/config/bpf/bpf.h | 5 +-
gcc/config/bpf/bpf.md | 97 ---
gcc/config/bpf/bpf.opt| 14 ++
gcc/doc/invoke.texi | 21 -
6 files changed, 133 insertions(+), 56 deletions(-)
diff --git a/gcc/config/bpf/bpf-opts.h b/gcc/config/bpf/bpf-opts.h
index 8282351cf045..92db01ec4d54 100644
--- a/gcc/config/bpf/bpf-opts.h
+++ b/gcc/config/bpf/bpf-opts.h
@@ -60,4 +60,10 @@ enum bpf_isa_version
ISA_V3,
};
+enum bpf_asm_dialect
+{
+ ASM_NORMAL,
+ ASM_PSEUDOC
+};
+
#endif /* ! BPF_OPTS_H */
diff --git a/gcc/config/bpf/bpf.cc b/gcc/config/bpf/bpf.cc
index e0324e1e0e08..1d3936871d60 100644
--- a/gcc/config/bpf/bpf.cc
+++ b/gcc/config/bpf/bpf.cc
@@ -873,16 +873,47 @@ bpf_output_call (rtx target)
return "";
}
+/* Print register name according to assembly dialect.
+ In normal syntax registers are printed like %rN where N is the
+ register number.
+ In pseudoc syntax, the register names do not feature a '%' prefix.
+ Additionally, the code 'w' denotes that the register should be printed
+ as wN instead of rN, where N is the register number, but only when the
+ value stored in the operand OP is 32-bit wide. */
+static void
+bpf_print_register (FILE *file, rtx op, int code)
+{
+ if(asm_dialect == ASM_NORMAL)
+fprintf (file, "%s", reg_names[REGNO (op)]);
+ else
+{
+ if (code == 'w' && GET_MODE (op) == SImode)
+ {
+ if (REGNO (op) == BPF_FP)
+ fprintf (file, "w10");
+ else
+ fprintf (file, "w%s", reg_names[REGNO (op)]+2);
+ }
+ else
+ {
+ if (REGNO (op) == BPF_FP)
+ fprintf (file, "r10");
+ else
+ fprintf (file, "%s", reg_names[REGNO (op)]+1);
+ }
+}
+}
+
/* Print an instruction operand. This function is called in the macro
PRINT_OPERAND defined in bpf.h */
void
-bpf_print_operand (FILE *file, rtx op, int code ATTRIBUTE_UNUSED)
+bpf_print_operand (FILE *file, rtx op, int code)
{
switch (GET_CODE (op))
{
case REG:
- fprintf (file, "%s", reg_names[REGNO (op)]);
+ bpf_print_register (file, op, code);
break;
case MEM:
output_address (GET_MODE (op), XEXP (op, 0));
@@ -936,7 +967,9 @@ bpf_print_operand_address (FILE *file, rtx addr)
switch (GET_CODE (addr))
{
case REG:
- fprintf (file, "[%s+0]", reg_names[REGNO (addr)]);
+ fprintf (file, asm_dialect == ASM_NORMAL ? "[" : "(");
+ bpf_print_register (file, addr, 0);
+ fprintf (file, asm_dialect == ASM_NORMAL ? "+0]" : "+0)");
break;
case PLUS:
{
@@ -945,9 +978,11 @@ bpf_print_operand_address (FILE *file, rtx addr)
if (GET_CODE (op0) == REG && GET_CODE (op1) == CONST_INT)
{
- fprintf (file, "[%s+", reg_names[REGNO (op0)]);
+ fprintf (file, asm_dialect == ASM_NORMAL ? "[" : "(");
+ bpf_print_register (file, op0, 0);
+ fprintf (file, "+");
output_addr_const (file, op1);
- fputs ("]", file);
+ fprintf (file, asm_dialect == ASM_NORMAL ? "]" : ")");
}
else
fatal_insn ("invalid address in operand", addr);
@@ -1816,7 +1851,6 @@ handle_attr_preserve (function *fn)
}
}
-
/* This pass finds accesses to structures marked with the BPF target attribute
__attribute__((preserve_access_index)). For every such access, a CO-RE
relocation record is generated, to be output in the .BTF.ext section. */
diff --git a/gcc/config/bpf/bpf.h b/gcc/config/bpf/bpf.h
index 344aca02d1bb..9561bf59b800 100644
--- a/gcc/config/bpf/bpf.h
+++ b/gcc/config/bpf/bpf.h
@@ -22,7 +22,8 @@
/ Controlling the Compilation Driver. */
-#define ASM_SPEC "%{mbig-endian:-EB} %{!mbig-endian:-EL} %{mxbpf:-mxbpf}"
+#define ASM_SPEC "%{mbig-endian:-EB} %{!mbig-endian:-EL} %{mxbpf:-mxbpf} " \
+ "%{masm=pseudoc:-mdialect=pseudoc}"
#define LINK_SPEC "%{mbig-endian:-EB} %{!mbig-endian:-EL}"
#define LIB_SPEC ""
#define
