[2/2] fix for gdb.reverse/finish-precsave.exp and gdb.reverse/finish-reverse.exp

Message ID c7a53afaa08d5755d41c1a254e09293ae75437b3.camel@us.ibm.com
State New
Headers
Series fix for gdb.reverse/finish-precsave.exp and gdb.reverse/finish-reverse.exp |

Commit Message

Carl Love Jan. 11, 2023, 6:27 p.m. UTC
  GDB maintainers:

This patch fixes the issues with the reverse-finish command on
PowerPC.  The reverse-finish command now correctly stops at the first
instruction in the source code line of the caller.  

The patch adds tests for calling a function via the GEP to the new test
gdb.reverse/finish-reverse-next.exp.

Please let me know if you have any comments on the patch.  Thanks.

                    Carl 

--------------------------------------------------------------
PowerPC: fix for gdb.reverse/finish-precsave.exp and gdb.reverse/finish-reverse.exp

PowerPC uses two entry points called the local entry point (LEP) and the
global entry point (GEP).  Normally the LEP is used when calling a
function.  However, if the table of contents (TOC) value in
register 3 is not valid the GEP is called to setup the TOC before execution
continues at the LEP.  When executing in reverse, the function
finish_backward sets the break point at the alternate entry point (GEP).
However if the forward execution enters via the normal entry point (LEP),
the reverse execution never sees the break point at the GEP of the
function.  Reverse execution continues until the next break point is
encountered or the end of the recorded log is reached causing gdb to stop
at the wrong place.

This patch adds a new address to struct execution_control_state to hold the
address of the alternate function start address, known as the GEP on
PowerPC.  The finish_backwards function is updated.  If the stopping point
is between the two entry points (the LEP and GEP on PowerPC) , the stepping
range is set to execute back to the alternate entry point (GEP on PowerPC).
Otherwise, a breakpoint is inserted at the normal entry point (LEP on
PowerPC).

Function process_event_stop_test checks uses a stepping range to stop
execution in the caller at the first instruction of the source code line.
Note, on systems that only support one entry point, the address of the two
entry points are the same.

Test finish-reverse-next.exp is updated to include tests for the
reverse-finish command when the function is entered via the normal entry
point (i.e. the LEP) and the alternate entry point (i.e. the GEP).

The patch has been tested on X86 and PowerPC with no regressions.
---
 gdb/infcmd.c                                  |  41 ++++---
 gdb/infrun.c                                  |  21 +++-
 .../gdb.reverse/finish-reverse-next.c         |  41 ++++++-
 .../gdb.reverse/finish-reverse-next.exp       | 107 +++++++++++++++---
 4 files changed, 175 insertions(+), 35 deletions(-)
  

Comments

Guinevere Larsen Jan. 13, 2023, 3:55 p.m. UTC | #1
On 11/01/2023 19:27, Carl Love via Gdb-patches wrote:
> GDB maintainers:
>
> This patch fixes the issues with the reverse-finish command on
> PowerPC.  The reverse-finish command now correctly stops at the first
> instruction in the source code line of the caller.
>
> The patch adds tests for calling a function via the GEP to the new test
> gdb.reverse/finish-reverse-next.exp.
>
> Please let me know if you have any comments on the patch.  Thanks.
I'm not all that familiar with PowerPC ABI and I dont have a computer 
handy to test that the patch fixes the problem, but the logic seems 
sound. Just a few nits inlined.
>
>                      Carl
>
> --------------------------------------------------------------
> PowerPC: fix for gdb.reverse/finish-precsave.exp and gdb.reverse/finish-reverse.exp
>
> PowerPC uses two entry points called the local entry point (LEP) and the
> global entry point (GEP).  Normally the LEP is used when calling a
> function.  However, if the table of contents (TOC) value in
> register 3 is not valid the GEP is called to setup the TOC before execution
> continues at the LEP.  When executing in reverse, the function
> finish_backward sets the break point at the alternate entry point (GEP).
> However if the forward execution enters via the normal entry point (LEP),
> the reverse execution never sees the break point at the GEP of the
> function.  Reverse execution continues until the next break point is
> encountered or the end of the recorded log is reached causing gdb to stop
> at the wrong place.
>
> This patch adds a new address to struct execution_control_state to hold the
> address of the alternate function start address, known as the GEP on
> PowerPC.  The finish_backwards function is updated.  If the stopping point
> is between the two entry points (the LEP and GEP on PowerPC) , the stepping
> range is set to execute back to the alternate entry point (GEP on PowerPC).
> Otherwise, a breakpoint is inserted at the normal entry point (LEP on
> PowerPC).
>
> Function process_event_stop_test checks uses a stepping range to stop
> execution in the caller at the first instruction of the source code line.
> Note, on systems that only support one entry point, the address of the two
> entry points are the same.
>
> Test finish-reverse-next.exp is updated to include tests for the
> reverse-finish command when the function is entered via the normal entry
> point (i.e. the LEP) and the alternate entry point (i.e. the GEP).
>
> The patch has been tested on X86 and PowerPC with no regressions.
> ---
>   gdb/infcmd.c                                  |  41 ++++---
>   gdb/infrun.c                                  |  21 +++-
>   .../gdb.reverse/finish-reverse-next.c         |  41 ++++++-
>   .../gdb.reverse/finish-reverse-next.exp       | 107 +++++++++++++++---
>   4 files changed, 175 insertions(+), 35 deletions(-)
>
> diff --git a/gdb/infcmd.c b/gdb/infcmd.c
> index 9c42efeae8d..8c30af448ce 100644
> --- a/gdb/infcmd.c
> +++ b/gdb/infcmd.c
> @@ -1722,22 +1722,28 @@ finish_backward (struct finish_command_fsm *sm)
>     sal = find_pc_line (func_addr, 0);
>   
>     frame_info_ptr frame = get_selected_frame (nullptr);
> +  struct gdbarch *gdbarch = get_frame_arch (frame);
> +  CORE_ADDR alt_entry_point = sal.pc;
> +  CORE_ADDR entry_point = alt_entry_point;
>   
> -  if (sal.pc != pc)
> +  if (gdbarch_skip_entrypoint_p (gdbarch))
>       {
> -      struct gdbarch *gdbarch = get_frame_arch (frame);
> +      /* Some architectures, like PowerPC use local and global entry
> +	 points.  There is only one Entry Point (GEP = LEP) for other
> +	 architectures.  The GEP is an alternate entry point that is used
> +	 setup the table of contents (TOC) in register r2 before execution
> +	 continues at the LEP.  The LEP is the normal entry point.
I don't think an explanation on why there are 2 entry points is 
necessary.  just mentioning that both exist is enough IMHO.
> +	 The value of entry_point was initialized to the alternate entry
> +	 point (GEP).  It will be adjusted if the normal entry point
> +	 (LEP) was used.  */
> +       entry_point = gdbarch_skip_entrypoint (gdbarch, entry_point);
>   
> -      /* Set a step-resume at the function's entry point.  Once that's
> -	 hit, we'll do one more step backwards.  */
> -      symtab_and_line sr_sal;
> -      sr_sal.pc = sal.pc;
> -      sr_sal.pspace = get_frame_program_space (frame);
> -      insert_step_resume_breakpoint_at_sal (gdbarch,
> -					    sr_sal, null_frame_id);
>       }
> -  else
> +
> +  if (alt_entry_point <= pc && pc <= entry_point)
>       {
> -      /* We are exactly at the function entry point.  Note that this
> +      /* We are exactly at the function entry point, or between the entry
> +	 point on platforms that have two (like PowerPC).  Note that this
>   	 can only happen at frame #0.
>   
>   	 When setting a step range, need to call set_step_info
> @@ -1746,8 +1752,17 @@ finish_backward (struct finish_command_fsm *sm)
>   
>         /* Return using a step range so we will keep stepping back
>   	 to the first instruction in the source code line.  */
> -      tp->control.step_range_start = sal.pc;
> -      tp->control.step_range_end = sal.pc;
> +      tp->control.step_range_start = alt_entry_point;
> +      tp->control.step_range_end = alt_entry_point;
I'm hesitant in this part. What if there is one instruction between the 
GEP and the LEP and the inferior happens to be stopped there? Could this 
happen? Like I said, I'm not familiar with the PPC abi, so excuse me if 
the answer is obvious, but it seems to me that the step_range_end could 
be set to the entry_point and we'd avoid this possibility.
> +    }
> +  else
> +    {
> +      symtab_and_line sr_sal;
> +      /* Set a step-resume at the function's entry point.  */
> +      sr_sal.pc = entry_point;
> +      sr_sal.pspace = get_frame_program_space (frame);
> +      insert_step_resume_breakpoint_at_sal (gdbarch,
> +					    sr_sal, null_frame_id);
>       }
>     proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
>   }
> diff --git a/gdb/infrun.c b/gdb/infrun.c
> index 8ed538ea9ec..89423556ec0 100644
> --- a/gdb/infrun.c
> +++ b/gdb/infrun.c
> @@ -1868,6 +1868,7 @@ struct execution_control_state
>   
>     struct target_waitstatus ws;
>     int stop_func_filled_in = 0;
> +  CORE_ADDR stop_func_alt_start = 0;
>     CORE_ADDR stop_func_start = 0;
>     CORE_ADDR stop_func_end = 0;
>     const char *stop_func_name = nullptr;
> @@ -4663,6 +4664,14 @@ fill_in_stop_func (struct gdbarch *gdbarch,
>   				    &block);
>         ecs->stop_func_name = gsi == nullptr ? nullptr : gsi->print_name ();
>   
> +      /* PowerPC functions have a Local Entry Point and a Global Entry
> +	 Point.  There is only one Entry Point (GEP = LEP) for other
> +	 architectures.  The GEP is an alternate entry point that is used
> +	 setup the table of contents (TOC) in register r2 before execution
> +	 continues at the LEP.  Save the alternate entry point address for
Ditto here about explaining LEP and GEP. Just saying that GEP is the 
alternate is probably enough.
> +	 use later.  */
> +      ecs->stop_func_alt_start = ecs->stop_func_start;
> +
>         /* The call to find_pc_partial_function, above, will set
>   	 stop_func_start and stop_func_end to the start and end
>   	 of the range containing the stop pc.  If this range
> @@ -4679,6 +4688,9 @@ fill_in_stop_func (struct gdbarch *gdbarch,
>   	    += gdbarch_deprecated_function_start_offset (gdbarch);
>   
>   	  if (gdbarch_skip_entrypoint_p (gdbarch))
> +	    /* The PowerPC architecture uses two entry points.  Stop at the
> +	       regular entry point (LEP on PowerPC) initially.  Will setup a
> +	       breakpoint for the alternate entry point (GEP) later.  */
>   	    ecs->stop_func_start
>   	      = gdbarch_skip_entrypoint (gdbarch, ecs->stop_func_start);
>   	}
> @@ -6738,8 +6750,7 @@ process_event_stop_test (struct execution_control_state *ecs)
>         delete_step_resume_breakpoint (ecs->event_thread);
>         fill_in_stop_func (gdbarch, ecs);
>   
> -      if (execution_direction == EXEC_REVERSE
> -	  && ecs->event_thread->stop_pc () == ecs->stop_func_start)
> +      if (execution_direction == EXEC_REVERSE)
Why is this change not in the previous patch?
>   	{
>   	  struct thread_info *tp = ecs->event_thread;
>   	  stop_pc_sal = find_pc_line (ecs->event_thread->stop_pc (), 0);
> @@ -6755,7 +6766,7 @@ process_event_stop_test (struct execution_control_state *ecs)
>   
>   	     Return using a step range so we will keep stepping back to the
>   	     first instruction in the source code line.  */
> -	  tp->control.step_range_start = ecs->stop_func_start;
> +	  tp->control.step_range_start = ecs->stop_func_alt_start;
>   	  tp->control.step_range_end = ecs->stop_func_start;
>   	  keep_going (ecs);
>   	  return;
> @@ -6892,8 +6903,10 @@ process_event_stop_test (struct execution_control_state *ecs)
>   	 (unless it's the function entry point, in which case
>   	 keep going back to the call point).  */
>         CORE_ADDR stop_pc = ecs->event_thread->stop_pc ();
> +
>         if (stop_pc == ecs->event_thread->control.step_range_start
> -	  && stop_pc != ecs->stop_func_start
> +	  && (stop_pc < ecs->stop_func_alt_start
> +	      || stop_pc > ecs->stop_func_start)
>   	  && execution_direction == EXEC_REVERSE)
>   	end_stepping_range (ecs);
>         else
> diff --git a/gdb/testsuite/gdb.reverse/finish-reverse-next.c b/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> index 42e41b5a2e0..55f81d2bc01 100644
> --- a/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> +++ b/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> @@ -1,4 +1,4 @@
> -/* This testcase is part of GDB, the GNU debugger.
> +j/* This testcase is part of GDB, the GNU debugger.
>   
>      Copyright 2012-2022 Free Software Foundation, Inc.
>   
> @@ -24,11 +24,37 @@
>      This test verifies the fix for gdb bugzilla:
>   
>      https://sourceware.org/bugzilla/show_bug.cgi?id=29927
> -*/
> +
> +   PowerPC supports two entry points to a function.  The normal entry point
> +   is called the local entry point (LEP).  The alternat entry point is called
> +   the global entry point (GEP).  The GEP is only used if the table of
> +   contents (TOC) value stored in register r2 needs to be setup prior to
> +   execution starting at the LEP.  A function call via a function pointer
> +   will entry via the GEP.  A normal function call will enter via the LEP.
> +
> +   This test has been expanded to include tests to verify the reverse-finish
> +   command works properly if the function is called via the GEP.  The original
> +   test only verified the reverse-finish command for a normal call that used
> +   the LEP.  */
>   
>   int
>   function1 (int a, int b)   // FUNCTION1
>   {
> +  /* The assembly code for this function when compiled for PowerPC is as
> +     follows:
> +
> +     0000000010000758 <function1>:
> +     10000758:	02 10 40 3c 	lis     r2,4098        <- GEP
> +     1000075c:	00 7f 42 38 	addi    r2,r2,32512
> +     10000760:	a6 02 08 7c 	mflr    r0             <- LEP
> +     10000764:	10 00 01 f8 	std     r0,16(r1)
> +     ....
> +
> +     When the function is called on PowerPC with function1 (a, b) the call
> +     enters at the Local Entry Point (LEP).  When the function is called via
> +     a function pointer, the Global Entry Point (GEP) for function1 is used.
> +     The GEP sets up register 2 before reaching the LEP.
> +  */
>     int ret = 0;
>   
>     ret = a + b;
> @@ -39,10 +65,19 @@ int
>   main(int argc, char* argv[])
>   {
>     int a, b;
> +  int (*funp) (int, int) = &function1;
> +
> +  /* Call function via Local Entry Point (LEP).  */
>   
>     a = 1;
>     b = 5;
>   
> -  function1 (a, b);   // CALL FUNCTION
> +  function1 (a, b);   // CALL VIA LEP
> +
> +  /* Call function via Global Entry Point (GEP).  */
> +  a = 10;
> +  b = 50;
> +
> +  funp (a, b);        // CALL VIA GEP
>     return 0;
>   }
> diff --git a/gdb/testsuite/gdb.reverse/finish-reverse-next.exp b/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
> index 7880de10ffc..fbc024b48b9 100644
> --- a/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
> +++ b/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
> @@ -31,6 +31,18 @@
>   # This test verifies the fix for gdb bugzilla:
>   #   https://sourceware.org/bugzilla/show_bug.cgi?id=29927
>   
> +# PowerPC supports two entry points to a function.  The normal entry point
> +# is called the local entry point (LEP).  The alternat entry point is called
> +# the global entry point (GEP).  The GEP is only used if the table of
> +# contents (TOC) value stored in register r2 needs to be setup prior to
> +# execution starting at the LEP.  A function call via a function pointer
> +# will entry via the GEP.  A normal function call will enter via the LEP.
> +#
> +# This test has been expanded to include tests to verify the reverse-finish
> +# command works properly if the function is called via the GEP.  The original
> +# test only verified the reverse-finish command for a normal call that used
> +# the LEP.
> +
>   if ![supports_reverse] {
>       return
>   }
> @@ -50,32 +62,32 @@ if [supports_process_record] {
>   }
>   
>   
> -### TEST 1: reverse finish from the entry point instruction in
> -### function1.
> +### TEST 1: reverse finish from the entry point instruction (LEP) in
> +### function1 when called using the normal entry point (LEP).
>   
>   # Set breakpoint at call to function1 in main.
> -set FUNCTION_test  [gdb_get_line_number "CALL FUNCTION" $srcfile]
> -gdb_test "break $srcfile:$FUNCTION_test" "Breakpoint $decimal at .*" \
> -    "set breakpoint on function1 call to stepi into function"
> +set LEP_test  [gdb_get_line_number "CALL VIA LEP" $srcfile]
> +gdb_test "break $srcfile:$LEP_test" "Breakpoint $decimal at .*" \
> +    "set breakpoint on function1 LEP call to stepi into function"
>   
>   # Continue to break point at function1 call in main.
>   gdb_test "continue" "Breakpoint $decimal,.*function1 \\(a, b\\).*" \
>       "stopped at function1 entry point instruction to stepi into function"
>   
>   # stepi until we see "{" indicating we entered function1
> -cmd_until "stepi" "CALL FUNCTION" "{" "stepi into function1 call"
> +cmd_until "stepi" "CALL VIA LEP" "{" "stepi into function1 call"
>   
>   delete_breakpoints
>   
> -gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL FUNCTION.*" \
> -    "reverse-finish function1 "
> +gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL VIA LEP.*" \
> +    "reverse-finish function1 LEP call from LEP "
>   
>   # Check to make sure we stopped at the first instruction in the source code
>   # line.  It should only take one reverse next command to get to the previous
>   # source line.   If GDB stops at the last instruction in the source code line
>   # it will take two reverse next instructions to get to the previous source
>   # line.
> -gdb_test "reverse-next" ".*b = 5;.*" "reverse next at b = 5, call from function"
> +gdb_test "reverse-next" ".*b = 5;.*" "reverse next at b = 5, call from LEP"
>   
>   # Clear the recorded log.
>   gdb_test "record stop"  "Process record is stopped.*" \
> @@ -83,26 +95,91 @@ gdb_test "record stop"  "Process record is stopped.*" \
>   gdb_test_no_output "record" "turn on process record for test2"
>   
>   
> -### TEST 2: reverse finish from the body of function1.
> +### TEST 2: reverse finish from the body of function1 when called using the
> +### normal entry point (LEP).
>   
>   # Set breakpoint at call to function1 in main.
> -gdb_test "break $srcfile:$FUNCTION_test" "Breakpoint $decimal at .*" \
> -    "set breakpoint on function1 call to step into body of function"
> +gdb_test "break $srcfile:$LEP_test" "Breakpoint $decimal at .*" \
> +    "set breakpoint on function1 LEP call to step into body of function"
>   
>   # Continue to break point at function1 call in main.
>   gdb_test "continue" "Breakpoint $decimal,.*function1 \\(a, b\\).*" \
> -    "stopped at function1 entry point instruction to step to body of function"
> +    "stopped at function1 entry point instruction to step body of function"
>   
>   delete_breakpoints
>   
>   # do a step instruction to get to the body of the function
>   gdb_test "step" ".*int ret = 0;.*" "step test 1"
>   
> -gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL FUNCTION.*" \
> -    "reverse-finish function1 call from function body"
> +gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL VIA LEP.*" \
> +    "reverse-finish function1 LEP call from function body"
>   
>   # Check to make sure we stopped at the first instruction in the source code
>   # line.  It should only take one reverse next command to get to the previous
>   # source line.
>   gdb_test "reverse-next" ".*b = 5;.*" \
>       "reverse next at b = 5, from function body"
> +
> +# Turn off record to clear logs and turn on again
> +gdb_test "record stop"  "Process record is stopped.*" \
> +    "turn off process record for test2"
> +gdb_test_no_output "record" "turn on process record for test3"
> +
> +
> +### TEST 3: reverse finish from the alternate entry point instruction (GEP) in
> +### function1 when called using the alternate entry point (GEP).
> +
> +# Set breakpoint at call to funp in main.
> +set GEP_test  [gdb_get_line_number "CALL VIA GEP" $srcfile]
> +gdb_test "break $srcfile:$GEP_test" "Breakpoint $decimal at .*" \
> +    "set breakpoint on function1 GEP call to stepi into function"
> +
> +# Continue to break point at funp call in main.
> +gdb_test "continue" "Breakpoint $decimal.*funp \\(a, b\\).*" \
> +    "stopped at funp entry point instruction"
> +
> +# stepi until we see "{" indicating we entered function.
> +cmd_until "stepi" "CALL VIA GEP" "{" "stepi into funp call"
> +
> +delete_breakpoints
> +
> +gdb_test "reverse-finish" ".*funp \\(a, b\\);.*" \
> +    "function1 GEP call call from GEP"
> +
> +# Check to make sure we stopped at the first instruction in the source code
> +# line.  It should only take one reverse next command to get to the previous
> +# source line.  If GDB stops at the last instruction in the source code line
> +# it will take two reverse next instructions to get to the previous source
> +# line.
> +gdb_test "reverse-next" ".*b = 50;.*" "reverse next at b = 50, call from GEP"
> +
> +# Turn off record to clear logs and turn on again
> +gdb_test "record stop"  "Process record is stopped.*" \
> +    "turn off process record for test3"
> +gdb_test_no_output "record" "turn on process record for test4"
> +
> +
> +### TEST 4: reverse finish from the body of function 1 when calling using the
> +### alternate entrypoint (GEP).
> +gdb_test "break $srcfile:$GEP_test" "Breakpoint $decimal at .*" \
> +    "set breakpoint on funp GEP call to step into body of function"
> +
> +# Continue to break point at funp call.
> +gdb_test "continue" "Breakpoint $decimal,.*funp \\(a, b\\).*" \
> +    "stopped at funp call"
> +
> +# Step into body of funp, called via GEP.
> +gdb_test "step" ".*int ret = 0;.*" "step test 2"
> +
> +delete_breakpoints
> +
> +gdb_test "reverse-finish" ".*funp \\(a, b\\);.*" \
> +    "reverse-finish function1 GEP call, from function body  "
> +
> +# Check to make sure we stopped at the first instruction in the source code
> +# line.  It should only take one reverse next command to get to the previous
> +# source line.  If GDB stops at the last instruction in the source code line
> +# it will take two reverse next instructions to get to the previous source
> +# line.
> +gdb_test "reverse-next" ".*b = 50;.*" \
> +    "reverse next at b = 50 from function body"
  
Carl Love Jan. 14, 2023, 6:08 p.m. UTC | #2
On Fri, 2023-01-13 at 16:55 +0100, Bruno Larsen wrote:
> On 11/01/2023 19:27, Carl Love via Gdb-patches wrote:
> > GDB maintainers:
> > 
> > This patch fixes the issues with the reverse-finish command on
> > PowerPC.  The reverse-finish command now correctly stops at the
> > first
> > instruction in the source code line of the caller.
> > 
> > The patch adds tests for calling a function via the GEP to the new
> > test
> > gdb.reverse/finish-reverse-next.exp.
> > 
> > Please let me know if you have any comments on the patch.  Thanks.
> I'm not all that familiar with PowerPC ABI and I dont have a
> computer 
> handy to test that the patch fixes the problem, but the logic seems 
> sound. Just a few nits inlined.
> >                      Carl
> > 
> > --------------------------------------------------------------
> > PowerPC: fix for gdb.reverse/finish-precsave.exp and
> > gdb.reverse/finish-reverse.exp
> > 
> > PowerPC uses two entry points called the local entry point (LEP)
> > and the
> > global entry point (GEP).  Normally the LEP is used when calling a
> > function.  However, if the table of contents (TOC) value in
> > register 3 is not valid the GEP is called to setup the TOC before
> > execution
> > continues at the LEP.  When executing in reverse, the function
> > finish_backward sets the break point at the alternate entry point
> > (GEP).
> > However if the forward execution enters via the normal entry point
> > (LEP),
> > the reverse execution never sees the break point at the GEP of the
> > function.  Reverse execution continues until the next break point
> > is
> > encountered or the end of the recorded log is reached causing gdb
> > to stop
> > at the wrong place.
> > 
> > This patch adds a new address to struct execution_control_state to
> > hold the
> > address of the alternate function start address, known as the GEP
> > on
> > PowerPC.  The finish_backwards function is updated.  If the
> > stopping point
> > is between the two entry points (the LEP and GEP on PowerPC) , the
> > stepping
> > range is set to execute back to the alternate entry point (GEP on
> > PowerPC).
> > Otherwise, a breakpoint is inserted at the normal entry point (LEP
> > on
> > PowerPC).
> > 
> > Function process_event_stop_test checks uses a stepping range to
> > stop
> > execution in the caller at the first instruction of the source code
> > line.
> > Note, on systems that only support one entry point, the address of
> > the two
> > entry points are the same.
> > 
> > Test finish-reverse-next.exp is updated to include tests for the
> > reverse-finish command when the function is entered via the normal
> > entry
> > point (i.e. the LEP) and the alternate entry point (i.e. the GEP).
> > 
> > The patch has been tested on X86 and PowerPC with no regressions.
> > ---
> >   gdb/infcmd.c                                  |  41 ++++---
> >   gdb/infrun.c                                  |  21 +++-
> >   .../gdb.reverse/finish-reverse-next.c         |  41 ++++++-
> >   .../gdb.reverse/finish-reverse-next.exp       | 107
> > +++++++++++++++---
> >   4 files changed, 175 insertions(+), 35 deletions(-)
> > 
> > diff --git a/gdb/infcmd.c b/gdb/infcmd.c
> > index 9c42efeae8d..8c30af448ce 100644
> > --- a/gdb/infcmd.c
> > +++ b/gdb/infcmd.c
> > @@ -1722,22 +1722,28 @@ finish_backward (struct finish_command_fsm
> > *sm)
> >     sal = find_pc_line (func_addr, 0);
> >   
> >     frame_info_ptr frame = get_selected_frame (nullptr);
> > +  struct gdbarch *gdbarch = get_frame_arch (frame);
> > +  CORE_ADDR alt_entry_point = sal.pc;
> > +  CORE_ADDR entry_point = alt_entry_point;
> >   
> > -  if (sal.pc != pc)
> > +  if (gdbarch_skip_entrypoint_p (gdbarch))
> >       {
> > -      struct gdbarch *gdbarch = get_frame_arch (frame);
> > +      /* Some architectures, like PowerPC use local and global
> > entry
> > +	 points.  There is only one Entry Point (GEP = LEP) for other
> > +	 architectures.  The GEP is an alternate entry point that is
> > used
> > +	 setup the table of contents (TOC) in register r2 before
> > execution
> > +	 continues at the LEP.  The LEP is the normal entry point.
> I don't think an explanation on why there are 2 entry points is 
> necessary.  just mentioning that both exist is enough IMHO.

OK, took out the additional detail in the comment.

> > +	 The value of entry_point was initialized to the alternate
> > entry
> > +	 point (GEP).  It will be adjusted if the normal entry point
> > +	 (LEP) was used.  */
> > +       entry_point = gdbarch_skip_entrypoint (gdbarch,
> > entry_point);
> >   
> > -      /* Set a step-resume at the function's entry point.  Once
> > that's
> > -	 hit, we'll do one more step backwards.  */
> > -      symtab_and_line sr_sal;
> > -      sr_sal.pc = sal.pc;
> > -      sr_sal.pspace = get_frame_program_space (frame);
> > -      insert_step_resume_breakpoint_at_sal (gdbarch,
> > -					    sr_sal, null_frame_id);
> >       }
> > -  else
> > +
> > +  if (alt_entry_point <= pc && pc <= entry_point)
> >       {
> > -      /* We are exactly at the function entry point.  Note that
> > this
> > +      /* We are exactly at the function entry point, or between
> > the entry
> > +	 point on platforms that have two (like PowerPC).  Note that
> > this
> >   	 can only happen at frame #0.
> >   
> >   	 When setting a step range, need to call set_step_info
> > @@ -1746,8 +1752,17 @@ finish_backward (struct finish_command_fsm
> > *sm)
> >   
> >         /* Return using a step range so we will keep stepping back
> >   	 to the first instruction in the source code line.  */
> > -      tp->control.step_range_start = sal.pc;
> > -      tp->control.step_range_end = sal.pc;
> > +      tp->control.step_range_start = alt_entry_point;
> > +      tp->control.step_range_end = alt_entry_point;
> I'm hesitant in this part. What if there is one instruction between
> the 
> GEP and the LEP and the inferior happens to be stopped there? Could
> this 
> happen? 

Yes, if the user did a step instruction from the caller and stopped on
the second instruction in the function.  Note, there is actually one
instruction between the GEP instruction and the LEP instruction. 

> Like I said, I'm not familiar with the PPC abi, so excuse me if 
> the answer is obvious, but it seems to me that the step_range_end
> could 
> be set to the entry_point and we'd avoid this possibility.

Yes, that might be a little safer.  Changed to set step_range_end to
entry_point. the LEP which occurs two instructions after the GEP.

> > +    }
> > +  else
> > +    {
> > +      symtab_and_line sr_sal;
> > +      /* Set a step-resume at the function's entry point.  */
> > +      sr_sal.pc = entry_point;
> > +      sr_sal.pspace = get_frame_program_space (frame);
> > +      insert_step_resume_breakpoint_at_sal (gdbarch,
> > +					    sr_sal, null_frame_id);
> >       }
> >     proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
> >   }
> > diff --git a/gdb/infrun.c b/gdb/infrun.c
> > index 8ed538ea9ec..89423556ec0 100644
> > --- a/gdb/infrun.c
> > +++ b/gdb/infrun.c
> > @@ -1868,6 +1868,7 @@ struct execution_control_state
> >   
> >     struct target_waitstatus ws;
> >     int stop_func_filled_in = 0;
> > +  CORE_ADDR stop_func_alt_start = 0;
> >     CORE_ADDR stop_func_start = 0;
> >     CORE_ADDR stop_func_end = 0;
> >     const char *stop_func_name = nullptr;
> > @@ -4663,6 +4664,14 @@ fill_in_stop_func (struct gdbarch *gdbarch,
> >   				    &block);
> >         ecs->stop_func_name = gsi == nullptr ? nullptr : gsi-
> > >print_name ();
> >   
> > +      /* PowerPC functions have a Local Entry Point and a Global
> > Entry
> > +	 Point.  There is only one Entry Point (GEP = LEP) for other
> > +	 architectures.  The GEP is an alternate entry point that is
> > used
> > +	 setup the table of contents (TOC) in register r2 before
> > execution
> > +	 continues at the LEP.  Save the alternate entry point address
> > for
> Ditto here about explaining LEP and GEP. Just saying that GEP is the 
> alternate is probably enough.

OK, removed the additional explanation from both places in the GDB
code.  I did leave the extra descripion in the test case where I gave
the sample assembly code.  My feeling is having that extra information
is useful in the test case to explain what the specific test scenarios
are doing and why is helpful.  Having the extra detail repeated three
times in the gdb source code and test case is probably a bit much.   

> > +	 use later.  */
> > +      ecs->stop_func_alt_start = ecs->stop_func_start;
> > +
> >         /* The call to find_pc_partial_function, above, will set
> >   	 stop_func_start and stop_func_end to the start and end
> >   	 of the range containing the stop pc.  If this range
> > @@ -4679,6 +4688,9 @@ fill_in_stop_func (struct gdbarch *gdbarch,
> >   	    += gdbarch_deprecated_function_start_offset (gdbarch);
> >   
> >   	  if (gdbarch_skip_entrypoint_p (gdbarch))
> > +	    /* The PowerPC architecture uses two entry points.  Stop at
> > the
> > +	       regular entry point (LEP on PowerPC) initially.  Will
> > setup a
> > +	       breakpoint for the alternate entry point (GEP)
> > later.  */
> >   	    ecs->stop_func_start
> >   	      = gdbarch_skip_entrypoint (gdbarch, ecs-
> > >stop_func_start);
> >   	}
> > @@ -6738,8 +6750,7 @@ process_event_stop_test (struct
> > execution_control_state *ecs)
> >         delete_step_resume_breakpoint (ecs->event_thread);
> >         fill_in_stop_func (gdbarch, ecs);
> >   
> > -      if (execution_direction == EXEC_REVERSE
> > -	  && ecs->event_thread->stop_pc () == ecs->stop_func_start)
> > +      if (execution_direction == EXEC_REVERSE)
> Why is this change not in the previous patch?

Looks like it didn't get moved when I was reversing the order of the
patches. 

Moved the change to the previous patch.

> >   	{
> >   	  struct thread_info *tp = ecs->event_thread;
> >   	  stop_pc_sal = find_pc_line (ecs->event_thread->stop_pc (),
> > 0);
> > @@ -6755,7 +6766,7 @@ process_event_stop_test (struct
> > execution_control_state *ecs)
> >   
> >   	     Return using a step range so we will keep stepping back to
> > the
> >   	     first instruction in the source code line.  */
> > -	  tp->control.step_range_start = ecs->stop_func_start;
> > +	  tp->control.step_range_start = ecs->stop_func_alt_start;
> >   	  tp->control.step_range_end = ecs->stop_func_start;
> >   	  keep_going (ecs);
> >   	  return;
> > @@ -6892,8 +6903,10 @@ process_event_stop_test (struct
> > execution_control_state *ecs)
> >   	 (unless it's the function entry point, in which case
> >   	 keep going back to the call point).  */
> >         CORE_ADDR stop_pc = ecs->event_thread->stop_pc ();
> > +
> >         if (stop_pc == ecs->event_thread->control.step_range_start
> > -	  && stop_pc != ecs->stop_func_start
> > +	  && (stop_pc < ecs->stop_func_alt_start
> > +	      || stop_pc > ecs->stop_func_start)
> >   	  && execution_direction == EXEC_REVERSE)
> >   	end_stepping_range (ecs);
> >         else
> > diff --git a/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> > b/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> > index 42e41b5a2e0..55f81d2bc01 100644
> > --- a/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> > +++ b/gdb/testsuite/gdb.reverse/finish-reverse-next.c
> > @@ -1,4 +1,4 @@
> > 

<snip>

> > diff --git a/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
> > b/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
> > index 7880de10ffc..fbc024b48b9 100644
> > --- a/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
> > +++ b/gdb/testsuite/gdb.reverse/finish-reverse-next.exp

<snip>

The comments for patch 1/2 about using gdb_breakpoint and
gdb_continue_to_breakpoint were also applied to the two new tests.

> > +
> > +### TEST 3: reverse finish from the alternate entry point
> > instruction (GEP) in
> > +### function1 when called using the alternate entry point (GEP).
> > +
> > +# Set breakpoint at call to funp in main.
> > +set GEP_test  [gdb_get_line_number "CALL VIA GEP" $srcfile]
> > +gdb_test "break $srcfile:$GEP_test" "Breakpoint $decimal at .*" \
> > +    "set breakpoint on function1 GEP call to stepi into function"
> > +
> > +# Continue to break point at funp call in main.
> > +gdb_test "continue" "Breakpoint $decimal.*funp \\(a, b\\).*" \
> > +    "stopped at funp entry point instruction"
> > +
> > +# stepi until we see "{" indicating we entered function.
> > +cmd_until "stepi" "CALL VIA GEP" "{" "stepi into funp call"
> > +
> > +delete_breakpoints
> > +
> > +gdb_test "reverse-finish" ".*funp \\(a, b\\);.*" \
> > +    "function1 GEP call call from GEP"
> > +
> > +# Check to make sure we stopped at the first instruction in the
> > source code
> > +# line.  It should only take one reverse next command to get to
> > the previous
> > +# source line.  If GDB stops at the last instruction in the source
> > code line
> > +# it will take two reverse next instructions to get to the
> > previous source
> > +# line.
> > +gdb_test "reverse-next" ".*b = 50;.*" "reverse next at b = 50,
> > call from GEP"
> > +
> > +# Turn off record to clear logs and turn on again
> > +gdb_test "record stop"  "Process record is stopped.*" \
> > +    "turn off process record for test3"
> > +gdb_test_no_output "record" "turn on process record for test4"
> > +
> > +
> > +### TEST 4: reverse finish from the body of function 1 when
> > calling using the
> > +### alternate entrypoint (GEP).
> > +gdb_test "break $srcfile:$GEP_test" "Breakpoint $decimal at .*" \
> > +    "set breakpoint on funp GEP call to step into body of
> > function"
> > +
> > +# Continue to break point at funp call.
> > +gdb_test "continue" "Breakpoint $decimal,.*funp \\(a, b\\).*" \
> > +    "stopped at funp call"
> > +
> > +# Step into body of funp, called via GEP.
> > +gdb_test "step" ".*int ret = 0;.*" "step test 2"
> > +
> > +delete_breakpoints
> > +
> > +gdb_test "reverse-finish" ".*funp \\(a, b\\);.*" \
> > +    "reverse-finish function1 GEP call, from function body  "
> > +
> > +# Check to make sure we stopped at the first instruction in the
> > source code
> > +# line.  It should only take one reverse next command to get to
> > the previous
> > +# source line.  If GDB stops at the last instruction in the source
> > code line
> > +# it will take two reverse next instructions to get to the
> > previous source
> > +# line.
> > +gdb_test "reverse-next" ".*b = 50;.*" \
> > +    "reverse next at b = 50 from function body"
> 
>
  

Patch

diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 9c42efeae8d..8c30af448ce 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -1722,22 +1722,28 @@  finish_backward (struct finish_command_fsm *sm)
   sal = find_pc_line (func_addr, 0);
 
   frame_info_ptr frame = get_selected_frame (nullptr);
+  struct gdbarch *gdbarch = get_frame_arch (frame);
+  CORE_ADDR alt_entry_point = sal.pc;
+  CORE_ADDR entry_point = alt_entry_point;
 
-  if (sal.pc != pc)
+  if (gdbarch_skip_entrypoint_p (gdbarch))
     {
-      struct gdbarch *gdbarch = get_frame_arch (frame);
+      /* Some architectures, like PowerPC use local and global entry
+	 points.  There is only one Entry Point (GEP = LEP) for other
+	 architectures.  The GEP is an alternate entry point that is used
+	 setup the table of contents (TOC) in register r2 before execution
+	 continues at the LEP.  The LEP is the normal entry point.
+	 The value of entry_point was initialized to the alternate entry
+	 point (GEP).  It will be adjusted if the normal entry point
+	 (LEP) was used.  */
+       entry_point = gdbarch_skip_entrypoint (gdbarch, entry_point);
 
-      /* Set a step-resume at the function's entry point.  Once that's
-	 hit, we'll do one more step backwards.  */
-      symtab_and_line sr_sal;
-      sr_sal.pc = sal.pc;
-      sr_sal.pspace = get_frame_program_space (frame);
-      insert_step_resume_breakpoint_at_sal (gdbarch,
-					    sr_sal, null_frame_id);
     }
-  else
+
+  if (alt_entry_point <= pc && pc <= entry_point)
     {
-      /* We are exactly at the function entry point.  Note that this
+      /* We are exactly at the function entry point, or between the entry
+	 point on platforms that have two (like PowerPC).  Note that this
 	 can only happen at frame #0.
 
 	 When setting a step range, need to call set_step_info
@@ -1746,8 +1752,17 @@  finish_backward (struct finish_command_fsm *sm)
 
       /* Return using a step range so we will keep stepping back
 	 to the first instruction in the source code line.  */
-      tp->control.step_range_start = sal.pc;
-      tp->control.step_range_end = sal.pc;
+      tp->control.step_range_start = alt_entry_point;
+      tp->control.step_range_end = alt_entry_point;
+    }
+  else
+    {
+      symtab_and_line sr_sal;
+      /* Set a step-resume at the function's entry point.  */
+      sr_sal.pc = entry_point;
+      sr_sal.pspace = get_frame_program_space (frame);
+      insert_step_resume_breakpoint_at_sal (gdbarch,
+					    sr_sal, null_frame_id);
     }
   proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
 }
diff --git a/gdb/infrun.c b/gdb/infrun.c
index 8ed538ea9ec..89423556ec0 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -1868,6 +1868,7 @@  struct execution_control_state
 
   struct target_waitstatus ws;
   int stop_func_filled_in = 0;
+  CORE_ADDR stop_func_alt_start = 0;
   CORE_ADDR stop_func_start = 0;
   CORE_ADDR stop_func_end = 0;
   const char *stop_func_name = nullptr;
@@ -4663,6 +4664,14 @@  fill_in_stop_func (struct gdbarch *gdbarch,
 				    &block);
       ecs->stop_func_name = gsi == nullptr ? nullptr : gsi->print_name ();
 
+      /* PowerPC functions have a Local Entry Point and a Global Entry
+	 Point.  There is only one Entry Point (GEP = LEP) for other
+	 architectures.  The GEP is an alternate entry point that is used
+	 setup the table of contents (TOC) in register r2 before execution
+	 continues at the LEP.  Save the alternate entry point address for
+	 use later.  */
+      ecs->stop_func_alt_start = ecs->stop_func_start;
+
       /* The call to find_pc_partial_function, above, will set
 	 stop_func_start and stop_func_end to the start and end
 	 of the range containing the stop pc.  If this range
@@ -4679,6 +4688,9 @@  fill_in_stop_func (struct gdbarch *gdbarch,
 	    += gdbarch_deprecated_function_start_offset (gdbarch);
 
 	  if (gdbarch_skip_entrypoint_p (gdbarch))
+	    /* The PowerPC architecture uses two entry points.  Stop at the
+	       regular entry point (LEP on PowerPC) initially.  Will setup a
+	       breakpoint for the alternate entry point (GEP) later.  */
 	    ecs->stop_func_start
 	      = gdbarch_skip_entrypoint (gdbarch, ecs->stop_func_start);
 	}
@@ -6738,8 +6750,7 @@  process_event_stop_test (struct execution_control_state *ecs)
       delete_step_resume_breakpoint (ecs->event_thread);
       fill_in_stop_func (gdbarch, ecs);
 
-      if (execution_direction == EXEC_REVERSE
-	  && ecs->event_thread->stop_pc () == ecs->stop_func_start)
+      if (execution_direction == EXEC_REVERSE)
 	{
 	  struct thread_info *tp = ecs->event_thread;
 	  stop_pc_sal = find_pc_line (ecs->event_thread->stop_pc (), 0);
@@ -6755,7 +6766,7 @@  process_event_stop_test (struct execution_control_state *ecs)
 
 	     Return using a step range so we will keep stepping back to the
 	     first instruction in the source code line.  */
-	  tp->control.step_range_start = ecs->stop_func_start;
+	  tp->control.step_range_start = ecs->stop_func_alt_start;
 	  tp->control.step_range_end = ecs->stop_func_start;
 	  keep_going (ecs);
 	  return;
@@ -6892,8 +6903,10 @@  process_event_stop_test (struct execution_control_state *ecs)
 	 (unless it's the function entry point, in which case
 	 keep going back to the call point).  */
       CORE_ADDR stop_pc = ecs->event_thread->stop_pc ();
+
       if (stop_pc == ecs->event_thread->control.step_range_start
-	  && stop_pc != ecs->stop_func_start
+	  && (stop_pc < ecs->stop_func_alt_start
+	      || stop_pc > ecs->stop_func_start)
 	  && execution_direction == EXEC_REVERSE)
 	end_stepping_range (ecs);
       else
diff --git a/gdb/testsuite/gdb.reverse/finish-reverse-next.c b/gdb/testsuite/gdb.reverse/finish-reverse-next.c
index 42e41b5a2e0..55f81d2bc01 100644
--- a/gdb/testsuite/gdb.reverse/finish-reverse-next.c
+++ b/gdb/testsuite/gdb.reverse/finish-reverse-next.c
@@ -1,4 +1,4 @@ 
-/* This testcase is part of GDB, the GNU debugger.
+j/* This testcase is part of GDB, the GNU debugger.
 
    Copyright 2012-2022 Free Software Foundation, Inc.
 
@@ -24,11 +24,37 @@ 
    This test verifies the fix for gdb bugzilla:
 
    https://sourceware.org/bugzilla/show_bug.cgi?id=29927
-*/
+
+   PowerPC supports two entry points to a function.  The normal entry point
+   is called the local entry point (LEP).  The alternat entry point is called
+   the global entry point (GEP).  The GEP is only used if the table of
+   contents (TOC) value stored in register r2 needs to be setup prior to
+   execution starting at the LEP.  A function call via a function pointer
+   will entry via the GEP.  A normal function call will enter via the LEP.
+
+   This test has been expanded to include tests to verify the reverse-finish
+   command works properly if the function is called via the GEP.  The original
+   test only verified the reverse-finish command for a normal call that used
+   the LEP.  */
 
 int
 function1 (int a, int b)   // FUNCTION1
 {
+  /* The assembly code for this function when compiled for PowerPC is as
+     follows:
+
+     0000000010000758 <function1>:
+     10000758:	02 10 40 3c 	lis     r2,4098        <- GEP
+     1000075c:	00 7f 42 38 	addi    r2,r2,32512
+     10000760:	a6 02 08 7c 	mflr    r0             <- LEP
+     10000764:	10 00 01 f8 	std     r0,16(r1)
+     ....
+
+     When the function is called on PowerPC with function1 (a, b) the call
+     enters at the Local Entry Point (LEP).  When the function is called via
+     a function pointer, the Global Entry Point (GEP) for function1 is used.
+     The GEP sets up register 2 before reaching the LEP.
+  */
   int ret = 0;
 
   ret = a + b;
@@ -39,10 +65,19 @@  int
 main(int argc, char* argv[])
 {
   int a, b;
+  int (*funp) (int, int) = &function1;
+
+  /* Call function via Local Entry Point (LEP).  */
 
   a = 1;
   b = 5;
 
-  function1 (a, b);   // CALL FUNCTION
+  function1 (a, b);   // CALL VIA LEP
+
+  /* Call function via Global Entry Point (GEP).  */
+  a = 10;
+  b = 50;
+
+  funp (a, b);        // CALL VIA GEP
   return 0;
 }
diff --git a/gdb/testsuite/gdb.reverse/finish-reverse-next.exp b/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
index 7880de10ffc..fbc024b48b9 100644
--- a/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
+++ b/gdb/testsuite/gdb.reverse/finish-reverse-next.exp
@@ -31,6 +31,18 @@ 
 # This test verifies the fix for gdb bugzilla:
 #   https://sourceware.org/bugzilla/show_bug.cgi?id=29927
 
+# PowerPC supports two entry points to a function.  The normal entry point
+# is called the local entry point (LEP).  The alternat entry point is called
+# the global entry point (GEP).  The GEP is only used if the table of
+# contents (TOC) value stored in register r2 needs to be setup prior to
+# execution starting at the LEP.  A function call via a function pointer
+# will entry via the GEP.  A normal function call will enter via the LEP.
+#
+# This test has been expanded to include tests to verify the reverse-finish
+# command works properly if the function is called via the GEP.  The original
+# test only verified the reverse-finish command for a normal call that used
+# the LEP.
+
 if ![supports_reverse] {
     return
 }
@@ -50,32 +62,32 @@  if [supports_process_record] {
 }
 
 
-### TEST 1: reverse finish from the entry point instruction in
-### function1.
+### TEST 1: reverse finish from the entry point instruction (LEP) in
+### function1 when called using the normal entry point (LEP).
 
 # Set breakpoint at call to function1 in main.
-set FUNCTION_test  [gdb_get_line_number "CALL FUNCTION" $srcfile]
-gdb_test "break $srcfile:$FUNCTION_test" "Breakpoint $decimal at .*" \
-    "set breakpoint on function1 call to stepi into function"
+set LEP_test  [gdb_get_line_number "CALL VIA LEP" $srcfile]
+gdb_test "break $srcfile:$LEP_test" "Breakpoint $decimal at .*" \
+    "set breakpoint on function1 LEP call to stepi into function"
 
 # Continue to break point at function1 call in main.
 gdb_test "continue" "Breakpoint $decimal,.*function1 \\(a, b\\).*" \
     "stopped at function1 entry point instruction to stepi into function"
 
 # stepi until we see "{" indicating we entered function1
-cmd_until "stepi" "CALL FUNCTION" "{" "stepi into function1 call"
+cmd_until "stepi" "CALL VIA LEP" "{" "stepi into function1 call"
 
 delete_breakpoints
 
-gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL FUNCTION.*" \
-    "reverse-finish function1 "
+gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL VIA LEP.*" \
+    "reverse-finish function1 LEP call from LEP "
 
 # Check to make sure we stopped at the first instruction in the source code
 # line.  It should only take one reverse next command to get to the previous
 # source line.   If GDB stops at the last instruction in the source code line
 # it will take two reverse next instructions to get to the previous source
 # line.
-gdb_test "reverse-next" ".*b = 5;.*" "reverse next at b = 5, call from function"
+gdb_test "reverse-next" ".*b = 5;.*" "reverse next at b = 5, call from LEP"
 
 # Clear the recorded log.
 gdb_test "record stop"  "Process record is stopped.*" \
@@ -83,26 +95,91 @@  gdb_test "record stop"  "Process record is stopped.*" \
 gdb_test_no_output "record" "turn on process record for test2"
 
 
-### TEST 2: reverse finish from the body of function1.
+### TEST 2: reverse finish from the body of function1 when called using the
+### normal entry point (LEP).
 
 # Set breakpoint at call to function1 in main.
-gdb_test "break $srcfile:$FUNCTION_test" "Breakpoint $decimal at .*" \
-    "set breakpoint on function1 call to step into body of function"
+gdb_test "break $srcfile:$LEP_test" "Breakpoint $decimal at .*" \
+    "set breakpoint on function1 LEP call to step into body of function"
 
 # Continue to break point at function1 call in main.
 gdb_test "continue" "Breakpoint $decimal,.*function1 \\(a, b\\).*" \
-    "stopped at function1 entry point instruction to step to body of function"
+    "stopped at function1 entry point instruction to step body of function"
 
 delete_breakpoints
 
 # do a step instruction to get to the body of the function
 gdb_test "step" ".*int ret = 0;.*" "step test 1"
 
-gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL FUNCTION.*" \
-    "reverse-finish function1 call from function body"
+gdb_test "reverse-finish" ".*function1 \\(a, b\\);   // CALL VIA LEP.*" \
+    "reverse-finish function1 LEP call from function body"
 
 # Check to make sure we stopped at the first instruction in the source code
 # line.  It should only take one reverse next command to get to the previous
 # source line.
 gdb_test "reverse-next" ".*b = 5;.*" \
     "reverse next at b = 5, from function body"
+
+# Turn off record to clear logs and turn on again
+gdb_test "record stop"  "Process record is stopped.*" \
+    "turn off process record for test2"
+gdb_test_no_output "record" "turn on process record for test3"
+
+
+### TEST 3: reverse finish from the alternate entry point instruction (GEP) in
+### function1 when called using the alternate entry point (GEP).
+
+# Set breakpoint at call to funp in main.
+set GEP_test  [gdb_get_line_number "CALL VIA GEP" $srcfile]
+gdb_test "break $srcfile:$GEP_test" "Breakpoint $decimal at .*" \
+    "set breakpoint on function1 GEP call to stepi into function"
+
+# Continue to break point at funp call in main.
+gdb_test "continue" "Breakpoint $decimal.*funp \\(a, b\\).*" \
+    "stopped at funp entry point instruction"
+
+# stepi until we see "{" indicating we entered function.
+cmd_until "stepi" "CALL VIA GEP" "{" "stepi into funp call"
+
+delete_breakpoints
+
+gdb_test "reverse-finish" ".*funp \\(a, b\\);.*" \
+    "function1 GEP call call from GEP"
+
+# Check to make sure we stopped at the first instruction in the source code
+# line.  It should only take one reverse next command to get to the previous
+# source line.  If GDB stops at the last instruction in the source code line
+# it will take two reverse next instructions to get to the previous source
+# line.
+gdb_test "reverse-next" ".*b = 50;.*" "reverse next at b = 50, call from GEP"
+
+# Turn off record to clear logs and turn on again
+gdb_test "record stop"  "Process record is stopped.*" \
+    "turn off process record for test3"
+gdb_test_no_output "record" "turn on process record for test4"
+
+
+### TEST 4: reverse finish from the body of function 1 when calling using the
+### alternate entrypoint (GEP).
+gdb_test "break $srcfile:$GEP_test" "Breakpoint $decimal at .*" \
+    "set breakpoint on funp GEP call to step into body of function"
+
+# Continue to break point at funp call.
+gdb_test "continue" "Breakpoint $decimal,.*funp \\(a, b\\).*" \
+    "stopped at funp call"
+
+# Step into body of funp, called via GEP.
+gdb_test "step" ".*int ret = 0;.*" "step test 2"
+
+delete_breakpoints
+
+gdb_test "reverse-finish" ".*funp \\(a, b\\);.*" \
+    "reverse-finish function1 GEP call, from function body  "
+
+# Check to make sure we stopped at the first instruction in the source code
+# line.  It should only take one reverse next command to get to the previous
+# source line.  If GDB stops at the last instruction in the source code line
+# it will take two reverse next instructions to get to the previous source
+# line.
+gdb_test "reverse-next" ".*b = 50;.*" \
+    "reverse next at b = 50 from function body"