[PATCH 175/203] Convert dtrace probes to use operations

Tom Tromey
2021-01-01T21:49:34Z

This changes dtrace to use the new operation type.

gdb/ChangeLog
2021-01-01 Tom Tromey <tom@tromey.com>

* gdbarch.sh (dtrace_parse_probe_argument): Change return type.
* gdbarch.h: Rebuild.
* gdbarch.c: Rebuild.
* dtrace-probe.c (dtrace_probe::build_arg_exprs): Update.
* amd64-linux-tdep.c (amd64_dtrace_parse_probe_argument): Change
return type.
(amd64_dtrace_parse_probe_argument): Update.
---
gdb/ChangeLog | 10 ++++++++++
gdb/amd64-linux-tdep.c | 39 ++++++++++++++-------------------------
gdb/dtrace-probe.c | 13 ++++++-------
gdb/gdbarch.c | 6 +++---
gdb/gdbarch.h | 4 ++--
gdb/gdbarch.sh | 2 +-
6 files changed, 36 insertions(+), 38 deletions(-)

diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
index f65ac4e4357..709c839cefa 100644
--- a/gdb/amd64-linux-tdep.c
+++ b/gdb/amd64-linux-tdep.c
@@ -41,6 +41,7 @@
#include "glibc-tdep.h"
#include "arch/amd64.h"
#include "target-descriptions.h"
+#include "expop.h"

/* The syscall's XML filename for i386. */
#define XML_SYSCALL_FILENAME_AMD64 "syscalls/amd64-linux.xml"
@@ -1733,17 +1734,16 @@ amd64_dtrace_disable_probe (struct gdbarch *gdbarch, CORE_ADDR addr)
/* Implementation of `gdbarch_dtrace_parse_probe_argument', as defined
in gdbarch.h. */

-static void
+static expr::operation_up
amd64_dtrace_parse_probe_argument (struct gdbarch *gdbarch,
- struct expr_builder *builder,
int narg)
{
- struct stoken str;
-
/* DTrace probe arguments can be found on the ABI-defined places for
regular arguments at the current PC. The probe abstraction
currently supports up to 12 arguments for probes. */

+ using namespace expr;
+
if (narg < 6)
{
static const int arg_reg_map[6] =
@@ -1757,12 +1757,7 @@ amd64_dtrace_parse_probe_argument (struct gdbarch *gdbarch,
};
int regno = arg_reg_map[narg];
const char *regname = user_reg_map_regnum_to_name (gdbarch, regno);
-
- write_exp_elt_opcode (builder, OP_REGISTER);
- str.ptr = regname;
- str.length = strlen (regname);
- write_exp_string (builder, str);
- write_exp_elt_opcode (builder, OP_REGISTER);
+ return make_operation<register_operation> (regname);
}
else
{
@@ -1770,27 +1765,21 @@ amd64_dtrace_parse_probe_argument (struct gdbarch *gdbarch,
const char *regname = user_reg_map_regnum_to_name (gdbarch, AMD64_RSP_REGNUM);

/* Displacement. */
- write_exp_elt_opcode (builder, OP_LONG);
- write_exp_elt_type (builder, builtin_type (gdbarch)->builtin_long);
- write_exp_elt_longcst (builder, narg - 6);
- write_exp_elt_opcode (builder, OP_LONG);
+ struct type *long_type = builtin_type (gdbarch)->builtin_long;
+ operation_up disp = make_operation<long_const_operation> (long_type,
+ narg - 6);

/* Register: SP. */
- write_exp_elt_opcode (builder, OP_REGISTER);
- str.ptr = regname;
- str.length = strlen (regname);
- write_exp_string (builder, str);
- write_exp_elt_opcode (builder, OP_REGISTER);
+ operation_up reg = make_operation<register_operation> (regname);

- write_exp_elt_opcode (builder, BINOP_ADD);
+ operation_up add = make_operation<add_operation> (std::move (disp),
+ std::move (reg));

/* Cast to long. */
- write_exp_elt_opcode (builder, UNOP_CAST);
- write_exp_elt_type (builder,
- lookup_pointer_type (builtin_type (gdbarch)->builtin_long));
- write_exp_elt_opcode (builder, UNOP_CAST);
+ operation_up cast = make_operation<unop_cast_operation> (std::move (add),
+ long_type);

- write_exp_elt_opcode (builder, UNOP_IND);
+ return make_operation<unop_ind_operation> (std::move (cast));
}
}

diff --git a/gdb/dtrace-probe.c b/gdb/dtrace-probe.c
index f4b6becbf61..3fa02ddaebe 100644
--- a/gdb/dtrace-probe.c
+++ b/gdb/dtrace-probe.c
@@ -32,6 +32,7 @@
#include "language.h"
#include "parser-defs.h"
#include "inferior.h"
+#include "expop.h"

/* The type of the ELF sections where we will find the DOF programs
with information about probes. */
@@ -629,20 +630,18 @@ dtrace_probe::build_arg_exprs (struct gdbarch *gdbarch)

/* The argument value, which is ABI dependent and casted to
`long int'. */
- gdbarch_dtrace_parse_probe_argument (gdbarch, &builder, argc);
+ expr::operation_up op = gdbarch_dtrace_parse_probe_argument (gdbarch,
+ argc);

/* Casting to the expected type, but only if the type was
recognized at probe load time. Otherwise the argument will
be evaluated as the long integer passed to the probe. */
if (arg.type != NULL)
- {
- write_exp_elt_opcode (&builder, UNOP_CAST);
- write_exp_elt_type (&builder, arg.type);
- write_exp_elt_opcode (&builder, UNOP_CAST);
- }
+ op = expr::make_operation<expr::unop_cast_operation> (std::move (op),
+ arg.type);

+ builder.set_operation (std::move (op));
arg.expr = builder.release ();
- prefixify_expression (arg.expr.get ());
++argc;
}
}
diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c
index 4bdf4068504..af95aa01cbd 100644
--- a/gdb/gdbarch.c
+++ b/gdb/gdbarch.c
@@ -4637,14 +4637,14 @@ gdbarch_dtrace_parse_probe_argument_p (struct gdbarch *gdbarch)
return gdbarch->dtrace_parse_probe_argument != NULL;
}

-void
-gdbarch_dtrace_parse_probe_argument (struct gdbarch *gdbarch, struct expr_builder *builder, int narg)
+expr::operation_up
+gdbarch_dtrace_parse_probe_argument (struct gdbarch *gdbarch, int narg)
{
gdb_assert (gdbarch != NULL);
gdb_assert (gdbarch->dtrace_parse_probe_argument != NULL);
if (gdbarch_debug >= 2)
fprintf_unfiltered (gdb_stdlog, "gdbarch_dtrace_parse_probe_argument called\n");
- gdbarch->dtrace_parse_probe_argument (gdbarch, builder, narg);
+ return gdbarch->dtrace_parse_probe_argument (gdbarch, narg);
}

void
diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h
index 2fef567c06f..3b9d8da4f61 100644
--- a/gdb/gdbarch.h
+++ b/gdb/gdbarch.h
@@ -1386,8 +1386,8 @@ extern void set_gdbarch_stap_adjust_register (struct gdbarch *gdbarch, gdbarch_s

extern bool gdbarch_dtrace_parse_probe_argument_p (struct gdbarch *gdbarch);

-typedef void (gdbarch_dtrace_parse_probe_argument_ftype) (struct gdbarch *gdbarch, struct expr_builder *builder, int narg);
-extern void gdbarch_dtrace_parse_probe_argument (struct gdbarch *gdbarch, struct expr_builder *builder, int narg);
+typedef expr::operation_up (gdbarch_dtrace_parse_probe_argument_ftype) (struct gdbarch *gdbarch, int narg);
+extern expr::operation_up gdbarch_dtrace_parse_probe_argument (struct gdbarch *gdbarch, int narg);
extern void set_gdbarch_dtrace_parse_probe_argument (struct gdbarch *gdbarch, gdbarch_dtrace_parse_probe_argument_ftype *dtrace_parse_probe_argument);

/* True if the given ADDR does not contain the instruction sequence
diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh
index e7c96159241..d68d3b7a425 100755
--- a/gdb/gdbarch.sh
+++ b/gdb/gdbarch.sh
@@ -1025,7 +1025,7 @@ M;std::string;stap_adjust_register;struct stap_parse_info *p, const std::string

# The expression to compute the NARTGth+1 argument to a DTrace USDT probe.
# NARG must be >= 0.
-M;void;dtrace_parse_probe_argument;struct expr_builder *builder, int narg;builder, narg
+M;expr::operation_up;dtrace_parse_probe_argument;int narg;narg

# True if the given ADDR does not contain the instruction sequence
# corresponding to a disabled DTrace is-enabled probe.
--
2.26.2