gdbarch software_single_step returns VEC (CORE_ADDR) *

This patch changes gdbarch method software_single_step to return a
vector of addresses on which GDB should insert breakpoints, and don't
insert breakpoints.  Instead, the caller of
gdbarch_software_single_step inserts breakpoints if the returned
vector is not NULL.

gdb:

2016-11-08  Yao Qi  <yao.qi@linaro.org>

	* aarch64-tdep.c (aarch64_software_single_step): Return
	VEC (CORE_ADDR) *.  Return NULL instead of 0.  Don't call
	insert_single_step_breakpoint.
	* alpha-tdep.c (alpha_deal_with_atomic_sequence): Likewise.
	(alpha_software_single_step): Likewise.
	* alpha-tdep.h (alpha_software_single_step): Update declaration.
	* arm-linux-tdep.c (arm_linux_software_single_step): Return
	VEC (CORE_ADDR) *.  Return NULL instead of 0.
	* arm-tdep.c (arm_software_single_step): Return NULL instead of	0.
	* arm-tdep.h (arm_software_single_step): Update declaration.
	* breakpoint.c (insert_single_step_breakpoints): New function.
	* breakpoint.h (insert_single_step_breakpoints): Declare.
	* cris-tdep.c (cris_software_single_step): Return
	VEC (CORE_ADDR) *.  Don't call insert_single_step_breakpoint.
	* gdbarch.sh (software_single_step): Change it to return
	VEC (CORE_ADDR) *.
	* gdbarch.c, gdbarch.h: Regenerated.
	* infrun.c (maybe_software_singlestep): Adjust.
	* mips-tdep.c (mips_deal_with_atomic_sequence): Return
	VEC (CORE_ADDR) *.  Don't call insert_single_step_breakpoint.
	(micromips_deal_with_atomic_sequence): Likewise.
	(deal_with_atomic_sequence): Likewise.
	(mips_software_single_step): Likewise.
	* mips-tdep.h (mips_software_single_step): Update declaration.
	* moxie-tdep.c (moxie_software_single_step): Likewise.
	* nios2-tdep.c (nios2_software_single_step): Likewise.
	* ppc-tdep.h (ppc_deal_with_atomic_sequence): Update
	declaration.
	* record-full.c (record_full_resume): Adjust.
	(record_full_wait_1): Likewise.
	* rs6000-aix-tdep.c (rs6000_software_single_step): Return
	VEC (CORE_ADDR) *.  Don't call insert_single_step_breakpoint.
	* rs6000-tdep.c	(ppc_deal_with_atomic_sequence): Return
	VEC (CORE_ADDR) *.  Don't call insert_single_step_breakpoint.
	* s390-linux-tdep.c (s390_software_single_step): Likewise.
	* sparc-tdep.c (sparc_software_single_step): Likewise.
	* spu-tdep.c (spu_software_single_step): Likewise.
	* tic6x-tdep.c (tic6x_software_single_step): Likewise.

1 files changed, 13 insertions, 15 deletions

diff --git a/gdb/alpha-tdep.c b/gdb/alpha-tdep.c
index 4b5c32d..a0485ef 100644
--- a/gdb/alpha-tdep.c
+++ b/gdb/alpha-tdep.c
@@ -765,11 +765,10 @@ static const int stq_c_opcode = 0x2f;
    is found, attempt to step through it.  A breakpoint is placed at the end of 
    the sequence.  */
 
-static int 
+static VEC (CORE_ADDR) *
 alpha_deal_with_atomic_sequence (struct frame_info *frame)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
-  struct address_space *aspace = get_frame_address_space (frame);
   CORE_ADDR pc = get_frame_pc (frame);
   CORE_ADDR breaks[2] = {-1, -1};
   CORE_ADDR loc = pc;
@@ -780,11 +779,12 @@ alpha_deal_with_atomic_sequence (struct frame_info *frame)
   int last_breakpoint = 0; /* Defaults to 0 (no breakpoints placed).  */  
   const int atomic_sequence_length = 16; /* Instruction sequence length.  */
   int bc_insn_count = 0; /* Conditional branch instruction count.  */
+  VEC (CORE_ADDR) *next_pcs = NULL;
 
   /* Assume all atomic sequences start with a LDL_L/LDQ_L instruction.  */
   if (INSN_OPCODE (insn) != ldl_l_opcode
       && INSN_OPCODE (insn) != ldq_l_opcode)
-    return 0;
+    return NULL;
 
   /* Assume that no atomic sequence is longer than "atomic_sequence_length" 
      instructions.  */
@@ -803,8 +803,8 @@ alpha_deal_with_atomic_sequence (struct frame_info *frame)
 	  immediate = (immediate ^ 0x400000) - 0x400000;
 
 	  if (bc_insn_count >= 1)
-	    return 0; /* More than one branch found, fallback 
-			 to the standard single-step code.  */
+	    return NULL; /* More than one branch found, fallback 
+			    to the standard single-step code.  */
 
 	  breaks[1] = loc + ALPHA_INSN_SIZE + immediate;
 
@@ -820,7 +820,7 @@ alpha_deal_with_atomic_sequence (struct frame_info *frame)
   /* Assume that the atomic sequence ends with a STL_C/STQ_C instruction.  */
   if (INSN_OPCODE (insn) != stl_c_opcode
       && INSN_OPCODE (insn) != stq_c_opcode)
-    return 0;
+    return NULL;
 
   closing_insn = loc;
   loc += ALPHA_INSN_SIZE;
@@ -835,11 +835,10 @@ alpha_deal_with_atomic_sequence (struct frame_info *frame)
 	  || (breaks[1] >= pc && breaks[1] <= closing_insn)))
     last_breakpoint = 0;
 
-  /* Effectively inserts the breakpoints.  */
   for (index = 0; index <= last_breakpoint; index++)
-    insert_single_step_breakpoint (gdbarch, aspace, breaks[index]);
+    VEC_safe_push (CORE_ADDR, next_pcs, breaks[index]);
 
-  return 1;
+  return next_pcs;
 }
 
 
@@ -1718,18 +1717,17 @@ alpha_next_pc (struct frame_info *frame, CORE_ADDR pc)
   return (pc + ALPHA_INSN_SIZE);
 }
 
-int
+VEC (CORE_ADDR) *
 alpha_software_single_step (struct frame_info *frame)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
-  struct address_space *aspace = get_frame_address_space (frame);
-  CORE_ADDR pc, next_pc;
+  CORE_ADDR pc;
+  VEC (CORE_ADDR) *next_pcs = NULL;
 
   pc = get_frame_pc (frame);
-  next_pc = alpha_next_pc (frame, pc);
 
-  insert_single_step_breakpoint (gdbarch, aspace, next_pc);
-  return 1;
+  VEC_safe_push (CORE_ADDR, next_pcs, alpha_next_pc (frame, pc));
+  return next_pcs;
 }