[PATCH 1/4] [gdb/testsuite] Simplify gdb.base/unwind-on-each-insn.exp

[Tom de Vries <tdevries@suse.de>]

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(-)

diff --git a/gdb/testsuite/gdb.base/unwind-on-each-insn.exp b/gdb/testsuite/gdb.base/unwind-on-each-insn.exp
index c8748d5ae14..5e822effaf1 100644
--- a/gdb/testsuite/gdb.base/unwind-on-each-insn.exp
+++ b/gdb/testsuite/gdb.base/unwind-on-each-insn.exp
@@ -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
+	}
     }
 }
-- 
2.35.3