From 4a7e075c3fdb862d1a9632fc3500c6e5111013fc Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Fri, 22 Apr 2016 12:14:40 +0100 Subject: Tweak gdb.reverse/step-precsave.exp and gdb.reverse/step-reverse.exp I see the following test fail in arm-linux with -marm and -fomit-frame-pointer, step callee () at /home/yao/SourceCode/gnu/gdb/git/gdb/testsuite/gdb.reverse/step-reverse.c:27 27 } /* RETURN FROM CALLEE */ (gdb) step main () at /home/yao/SourceCode/gnu/gdb/git/gdb/testsuite/gdb.reverse/step-reverse.c:58 58 callee(); /* STEP INTO THIS CALL */ (gdb) FAIL: gdb.reverse/step-precsave.exp: reverse step into fn call As we can see, the "step" has already stepped into the function callee, but in the last line. The second "step" attempts to step to function body, but it goes out of callee, which isn't expected. The program is compiled with -marm and -fomit-frame-pointer, the function callee is prologue-less, because nothing needs to be saved on stack, (gdb) disassemble callee Dump of assembler code for function callee: 0x00010680 <+0>: movw r3, #2364 ; 0x93c 0x00010684 <+4>: movt r3, #2 0x00010688 <+8>: ldr r3, [r3] 0x0001068c <+12>: add r2, r3, #1 0x00010690 <+16>: movw r3, #2364 ; 0x93c 0x00010694 <+20>: movt r3, #2 0x00010698 <+24>: str r2, [r3] 0x0001069c <+28>: mov r3, #0 0x000106a0 <+32>: mov r0, r3 0x000106a4 <+36>: bx lr program stops at the 0x106a0 (passed the epilogue) after the first "step". When second "step" is executed, the stepping range is [0x10680-0x106a0], which starts from the first instruction of function callee (because it doesn't have prologue). infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=0, current thread [LWP 2461] at 0x1069c^M infrun: prepare_to_wait^M infrun: target_wait (-1.0.0, status) =^M infrun: 2461.2461.0 [LWP 2461],^M infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP^M infrun: TARGET_WAITKIND_STOPPED^M infrun: stop_pc = 0x10698^M infrun: stepping inside range [0x10680-0x106a0] When program goes out of the range, it stops at the caller of callee, and test fails. IOW, if function callee has prologue, the stepping range won't start from the first instruction of the function, and program stops at the prologue and test passes. IMO, GDB does nothing wrong, but test shouldn't expect the program stops in callee after the second "step". I decide to fix test rather than GDB. In this patch, I change to test to do one "step", and check the program is still in callee, then, do multiple "step" until program goes out of the callee. gdb/testsuite: 2016-04-22 Yao Qi * gdb.reverse/step-precsave.exp: Do one step and test program stops in "callee" and do multiple steps until program goes out of "callee". * gdb.reverse/step-reverse.exp: Likewise. --- gdb/testsuite/gdb.reverse/step-reverse.exp | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'gdb/testsuite/gdb.reverse/step-reverse.exp') diff --git a/gdb/testsuite/gdb.reverse/step-reverse.exp b/gdb/testsuite/gdb.reverse/step-reverse.exp index fbf41e8..6f1e8b6 100644 --- a/gdb/testsuite/gdb.reverse/step-reverse.exp +++ b/gdb/testsuite/gdb.reverse/step-reverse.exp @@ -213,21 +213,26 @@ gdb_test_multiple "stepi" "$test_message" { # step backward into function (thru return) -set test_message "reverse step into fn call" +gdb_test "step" "(RETURN FROM CALLEE|ARRIVED IN CALLEE).*" \ + "reverse step into fn call" + +# step backward out of called function (thru call) + +set test_message "reverse step out of called fn" gdb_test_multiple "step" "$test_message" { - -re "RETURN FROM CALLEE.*$gdb_prompt $" { + -re "STEP INTO THIS CALL.*.*$gdb_prompt $" { + pass "$test_message" + } + -re "ARRIVED IN CALLEE.*$gdb_prompt $" { send_gdb "step\n" exp_continue } - -re "ARRIVED IN CALLEE.*$gdb_prompt $" { - pass "$test_message" + -re "ENTER CALLEE.*$gdb_prompt $" { + send_gdb "step\n" + exp_continue } } -# step backward out of called function (thru call) - -gdb_test "step" ".*STEP INTO THIS CALL.*" "reverse step out of called fn" - # next backward over call gdb_test "next" ".*NEXT OVER THIS CALL.*" "reverse next over call" -- cgit v1.1