Re: [PATCH 3/5 v4] Fix argument to compiled_cond, and add cases for compiled-condition.

[Yao Qi <qiyaoltc@gmail.com>]

Wei-cheng Wang <cole945@gmail.com> writes:

> * Fix generating emit-reg op by passing register buffer to compiled_cond.
> * Add a new function for testing compiled-cond by checking whether
>   based on a given CONDEXP, a list of expected values should be collected.
>
> ---
>
> gdb/gdbserver/ChangeLog
>
> 2015-06-27  Wei-cheng Wang  <cole945@gmail.com>
>
> 	* tracepoint.c (eval_result_type): Change prototype.
> 	(condition_true_at_tracepoint): Fix argument to compiled_cond.
>
> gdb/testsuite/ChangeLog
>
> 2015-06-27  Wei-cheng Wang  <cole945@gmail.com>
>
> 	* gdb.trace/ftrace.exp: (test_ftrace_condition) New function
> 	for testing bytecode compilation.

It was approved by Pedro, and I test this patch again on x86_64-linux,
no regressions.  Wei-cheng Wang has already had copyright assignment.  I'll
push this patch in as below.

-- 
Yao (齐尧)

From 93f470eba920b53d6bc1d46f855aec4398c1b8b7 Mon Sep 17 00:00:00 2001
From: Wei-cheng Wang <cole945@gmail.com>
Date: Wed, 16 Sep 2015 16:20:51 +0100
Subject: [PATCH] Fix argument to compiled_cond, and add cases for
 compiled-condition.

This patch fixes the argument passed to compiled_cond.  It should be
regs buffer instead of tracepoint_hit_ctx.  Test case is added as
well for testing compiled-cond.

gdb/gdbserver/ChangeLog

2015-09-16  Wei-cheng Wang  <cole945@gmail.com>

	* tracepoint.c (eval_result_type): Change prototype.
	(condition_true_at_tracepoint): Fix argument to compiled_cond.

gdb/testsuite/ChangeLog

2015-09-16  Wei-cheng Wang  <cole945@gmail.com>

	* gdb.trace/ftrace.exp: (test_ftrace_condition) New function
	for testing bytecode compilation.

diff --git a/gdb/gdbserver/tracepoint.c b/gdb/gdbserver/tracepoint.c
index fd010ae..5e34eba 100644
--- a/gdb/gdbserver/tracepoint.c
+++ b/gdb/gdbserver/tracepoint.c
@@ -695,7 +695,7 @@ enum tracepoint_type
 
 struct tracepoint_hit_ctx;
 
-typedef enum eval_result_type (*condfn) (struct tracepoint_hit_ctx *,
+typedef enum eval_result_type (*condfn) (unsigned char *,
 					 ULONGEST *);
 
 /* The definition of a tracepoint.  */
@@ -4907,7 +4907,10 @@ condition_true_at_tracepoint (struct tracepoint_hit_ctx *ctx,
      used.  */
 #ifdef IN_PROCESS_AGENT
   if (tpoint->compiled_cond)
-    err = ((condfn) (uintptr_t) (tpoint->compiled_cond)) (ctx, &value);
+    {
+      struct fast_tracepoint_ctx *fctx = (struct fast_tracepoint_ctx *) ctx;
+      err = ((condfn) (uintptr_t) (tpoint->compiled_cond)) (fctx->regs, &value);
+    }
   else
 #endif
     {
diff --git a/gdb/testsuite/gdb.trace/ftrace.exp b/gdb/testsuite/gdb.trace/ftrace.exp
index f2d8002..a8eb515 100644
--- a/gdb/testsuite/gdb.trace/ftrace.exp
+++ b/gdb/testsuite/gdb.trace/ftrace.exp
@@ -178,6 +178,42 @@ proc test_fast_tracepoints {} {
     }
 }
 
+# Test compiled-condition
+# CONDEXP is the condition expression to be compiled.
+# VAR is the variable to be collected for testing.
+# LIST is a list of expected values of VAR should be collected
+# based on the CONDEXP.
+proc test_ftrace_condition { condexp var list } \
+{ with_test_prefix "ond $condexp" \
+{
+    global executable
+    global hex
+
+    clean_restart ${executable}
+    if ![runto_main] {
+	fail "Can't run to main to check for trace support"
+	return -1
+    }
+
+    gdb_test "break end" ".*" ""
+    gdb_test "tvariable \$tsv = 0"
+    gdb_test "ftrace set_point if $condexp" "Fast tracepoint .*"
+    gdb_trace_setactions "set action for tracepoint .*" "" \
+	"collect $var" "^$"
+
+    gdb_test_no_output "tstart" ""
+    gdb_test "continue" "Continuing\\.\[ \r\n\]+Breakpoint.*" ""
+    gdb_test_no_output "tstop" ""
+
+    set i 0
+    foreach expval $list {
+	gdb_test "tfind" "Found trace frame $i, tracepoint .*" "tfind frame $i"
+	gdb_test "print $var" "\\$\[0-9\]+ = $expval\[\r\n\]" "expect $expval"
+	set i [expr $i + 1]
+    }
+    gdb_test "tfind" "Target failed to find requested trace frame\."
+}}
+
 gdb_reinitialize_dir $srcdir/$subdir
 
 if { [gdb_test "info sharedlibrary" ".*${libipa}.*" "IPA loaded"] != 0 } {
@@ -186,3 +222,31 @@ if { [gdb_test "info sharedlibrary" ".*${libipa}.*" "IPA loaded"] != 0 } {
 }
 
 test_fast_tracepoints
+
+# Test conditional goto and simple expression.
+test_ftrace_condition "globvar > 7" "globvar" { 8 9 10 }
+test_ftrace_condition "globvar < 4" "globvar" { 1 2 3 }
+test_ftrace_condition "globvar >= 7" "globvar" { 7 8 9 10 }
+test_ftrace_condition "globvar <= 4" "globvar" { 1 2 3 4 }
+test_ftrace_condition "globvar == 5" "globvar" { 5 }
+test_ftrace_condition "globvar != 5" "globvar" { 1 2 3 4 6 7 8 9 10 }
+test_ftrace_condition "globvar > 3 && globvar < 7" "globvar" { 4 5 6 }
+test_ftrace_condition "globvar < 3 || globvar > 7" "globvar" { 1 2 8 9 10 }
+test_ftrace_condition "(globvar << 2) + 1 == 29" "globvar" { 7 }
+test_ftrace_condition "(globvar >> 2) == 2" "globvar" { 8 9 10 }
+
+# Test emit_call by accessing trace state variables.
+test_ftrace_condition "(\$tsv = \$tsv + 2) > 10" "globvar" { 6 7 8 9 10 }
+
+# This expression is used for testing emit_reg.
+if [is_amd64_regs_target] {
+    set arg0exp "\$rdi"
+} elseif [is_x86_like_target] {
+    set arg0exp "*(int *) (\$ebp + 8)"
+} else {
+    set arg0exp ""
+}
+
+if { "$arg0exp" != "" } {
+    test_ftrace_condition "($arg0exp > 500)" "globvar" { 6 7 8 9 10 }
+}