[1/4,gdb/testsuite] Simplify gdb.base/unwind-on-each-insn.exp
Commit Message
In test-case gdb.base/unwind-on-each-insn.exp, we try to determine the last
insn in function foo.
This in it self is fragile, as demonstrated by commit 91836f41e20 ("Powerpc
fix for gdb.base/unwind-on-each-insn.exp").
But the purpose of finding the last insn is to stop stepping in foo when
arriving at that last insn.
There is however no guarantee that:
- the last insn is actually executed, nor
- that the last insn is executed last, nor
- that the last insn is executed once.
Fix this by simplying the test-case to continue stepping till stepping out of
foo.
Tested on x86_64-linux.
---
.../gdb.base/unwind-on-each-insn.exp | 62 ++++---------------
1 file changed, 11 insertions(+), 51 deletions(-)
Comments
On 1/19/23 11:46, Tom de Vries via Gdb-patches wrote:
> In test-case gdb.base/unwind-on-each-insn.exp, we try to determine the last
> insn in function foo.
>
> This in it self is fragile, as demonstrated by commit 91836f41e20 ("Powerpc
> fix for gdb.base/unwind-on-each-insn.exp").
>
> But the purpose of finding the last insn is to stop stepping in foo when
> arriving at that last insn.
>
> There is however no guarantee that:
> - the last insn is actually executed, nor
> - that the last insn is executed last, nor
> - that the last insn is executed once.
>
> Fix this by simplying the test-case to continue stepping till stepping out of
> foo.
>
I re-read the commit log, found it not clear enough, and decided to make
the difference between:
- last disassembled insn, and
- last insn executed before returning to main.
a bit more explicit.
Committed as attached.
Thanks,
- Tom
@@ -73,51 +73,6 @@ set main_fid [get_fid]
gdb_breakpoint "*foo"
gdb_continue_to_breakpoint "enter foo"
-# Figure out the range of addresses covered by this function.
-set last_addr_in_foo ""
-
-# The disassembly of foo on PowerPC looks like:
-# Dump of assembler code for function foo:
-# => 0x00000000100006dc <+0>: std r31,-8(r1)
-# 0x00000000100006e0 <+4>: stdu r1,-48(r1)
-# 0x00000000100006e4 <+8>: mr r31,r1
-# 0x00000000100006e8 <+12>: nop
-# 0x00000000100006ec <+16>: addi r1,r31,48
-# 0x00000000100006f0 <+20>: ld r31,-8(r1)
-# 0x00000000100006f4 <+24>: blr
-# 0x00000000100006f8 <+28>: .long 0x0
-# 0x00000000100006fc <+32>: .long 0x0
-# 0x0000000010000700 <+36>: .long 0x1000180
-# End of assembler dump.
-#
-# The last instruction in function foo is blr. Need to ignore the .long
-# entries following the blr instruction.
-
-gdb_test_multiple "disassemble foo" "" {
- -re "^disassemble foo\r\n" {
- exp_continue
- }
-
- -re "^Dump of assembler code for function foo:\r\n" {
- exp_continue
- }
-
- -re "^...($hex) \[<>+0-9:\s\t\]*\.long\[\s\t\]*\[^\r\n\]*\r\n" {
- exp_continue
- }
-
- -re "^...($hex) \[^\r\n\]+\r\n" {
- set last_addr_in_foo $expect_out(1,string)
- exp_continue
- }
-
- -wrap -re "^End of assembler dump\\." {
- gdb_assert { ![string equal $last_addr_in_foo ""] } \
- "found some addresses in foo"
- pass $gdb_test_name
- }
-}
-
# Record the current stack-pointer, and the frame base address.
lassign [get_sp_and_fba "in foo"] foo_sp foo_fba
set foo_fid [get_fid]
@@ -158,11 +113,6 @@ for { set i_count 1 } { true } { incr i_count } {
# Move back to the inner most frame.
gdb_test "frame 0" ".*"
- set pc [get_hexadecimal_valueof "\$pc" "*UNKNOWN*"]
- if { $pc == $last_addr_in_foo } {
- break
- }
-
if { $i_count > 100 } {
# We expect a handful of instructions, if we reach 100,
# something is going wrong. Avoid an infinite loop.
@@ -170,6 +120,16 @@ for { set i_count 1 } { true } { incr i_count } {
break
}
- gdb_test "stepi" ".*"
+ set in_foo 0
+ gdb_test_multiple "stepi" "" {
+ -re -wrap "$hex in foo \\(\\)" {
+ set in_foo 1
+ }
+ -re -wrap "" {}
+ }
+
+ if { ! $in_foo } {
+ break
+ }
}
}