1 files changed, 284 insertions, 25 deletions

diff --git a/gdb/loongarch-tdep.c b/gdb/loongarch-tdep.c
index 092127dd..9ee0eb3 100644
--- a/gdb/loongarch-tdep.c
+++ b/gdb/loongarch-tdep.c
@@ -26,6 +26,7 @@
 #include "gdbcore.h"
 #include "linux-record.h"
 #include "loongarch-tdep.h"
+#include "prologue-value.h"
 #include "record.h"
 #include "record-full.h"
 #include "reggroups.h"
@@ -34,6 +35,33 @@
 #include "trad-frame.h"
 #include "user-regs.h"
 
+/* LoongArch frame cache structure.  */
+struct loongarch_frame_cache
+{
+  /* The program counter at the start of the function.  It is used to
+     identify this frame as a prologue frame.  */
+  CORE_ADDR func;
+
+  /* The stack pointer at the time this frame was created; i.e. the
+     caller's stack pointer when this function was called.  It is used
+     to identify this frame.  */
+  CORE_ADDR prev_sp;
+
+  CORE_ADDR pc;
+
+  int available_p;
+
+  /* This register stores the frame base of the frame.  */
+  int framebase_reg;
+
+  /* The framebase_offset is the distance from frame base to the prev_sp,
+     so the value of framebase_reg is just prev_sp - framebase_offset. */
+  int framebase_offset;
+
+  /* Saved register offsets.  */
+  trad_frame_saved_reg *saved_regs;
+};
+
 /* Fetch the instruction at PC.  */
 
 static insn_t
@@ -74,7 +102,9 @@ loongarch_insn_is_cond_branch (insn_t insn)
       || (insn & 0xfc000000) == 0x68000000	/* bltu  */
       || (insn & 0xfc000000) == 0x6c000000	/* bgeu  */
       || (insn & 0xfc000000) == 0x40000000	/* beqz  */
-      || (insn & 0xfc000000) == 0x44000000)	/* bnez  */
+      || (insn & 0xfc000000) == 0x44000000	/* bnez  */
+      || (insn & 0xfc000300) == 0x48000000	/* bceqz  */
+      || (insn & 0xfc000300) == 0x48000100)	/* bcnez  */
     return true;
   return false;
 }
@@ -96,7 +126,9 @@ static bool
 loongarch_insn_is_ll (insn_t insn)
 {
   if ((insn & 0xff000000) == 0x20000000		/* ll.w  */
-      || (insn & 0xff000000) == 0x22000000)	/* ll.d  */
+      || (insn & 0xff000000) == 0x22000000	/* ll.d  */
+      || (insn & 0xfffffc00) == 0x38578000	/* llacq.w  */
+      || (insn & 0xfffffc00) == 0x38578800)	/* llacq.d  */
     return true;
   return false;
 }
@@ -107,7 +139,10 @@ static bool
 loongarch_insn_is_sc (insn_t insn)
 {
   if ((insn & 0xff000000) == 0x21000000		/* sc.w  */
-      || (insn & 0xff000000) == 0x23000000)	/* sc.d  */
+      || (insn & 0xff000000) == 0x23000000	/* sc.d  */
+      || (insn & 0xffff8000) == 0x38570000	/* sc.q  */
+      || (insn & 0xfffffc00) == 0x38578400	/* screl.w  */
+      || (insn & 0xfffffc00) == 0x38578c00)	/* screl.d  */
     return true;
   return false;
 }
@@ -118,13 +153,23 @@ loongarch_insn_is_sc (insn_t insn)
 static CORE_ADDR
 loongarch_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc,
 			 CORE_ADDR limit_pc, const frame_info_ptr &this_frame,
-			 struct trad_frame_cache *this_cache)
+			 struct loongarch_frame_cache *this_cache)
 {
   CORE_ADDR cur_pc = start_pc, prologue_end = 0;
   int32_t sp = LOONGARCH_SP_REGNUM;
   int32_t fp = LOONGARCH_FP_REGNUM;
+  int32_t ra = LOONGARCH_RA_REGNUM;
   int32_t reg_value[32] = {0};
   int32_t reg_used[32] = {1, 0};
+  int i;
+
+  /* Track 32 GPR, ORIG_A0, PC, BADV in prologue.  */
+  pv_t regs[LOONGARCH_USED_NUM_GREGSET];
+
+  for (i = 0; i < LOONGARCH_USED_NUM_GREGSET; i++)
+    regs[i] = pv_register (i, 0);
+
+  pv_area stack (LOONGARCH_SP_REGNUM, gdbarch_addr_bit (gdbarch));
 
   while (cur_pc < limit_pc)
     {
@@ -134,27 +179,40 @@ loongarch_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc,
       int32_t rj = loongarch_decode_imm ("5:5", insn, 0);
       int32_t rk = loongarch_decode_imm ("10:5", insn, 0);
       int32_t si12 = loongarch_decode_imm ("10:12", insn, 1);
+      int32_t si14 = loongarch_decode_imm ("10:14", insn, 1);
       int32_t si20 = loongarch_decode_imm ("5:20", insn, 1);
 
       if ((insn & 0xffc00000) == 0x02c00000	/* addi.d sp,sp,si12  */
 	  && rd == sp && rj == sp && si12 < 0)
 	{
 	  prologue_end = cur_pc + insn_len;
+	  regs[rd] = pv_add_constant (regs[rj], si12);
 	}
       else if ((insn & 0xffc00000) == 0x02c00000 /* addi.d fp,sp,si12  */
 	       && rd == fp && rj == sp && si12 > 0)
 	{
 	  prologue_end = cur_pc + insn_len;
+	  regs[rd] = pv_add_constant (regs[rj], si12);
 	}
       else if ((insn & 0xffc00000) == 0x29c00000 /* st.d rd,sp,si12  */
 	       && rj == sp)
 	{
 	  prologue_end = cur_pc + insn_len;
+	  /* ra, fp, s0~s8 are saved by callee with sp as a base */
+	  if ((rd >= fp && rd <= fp + 9) || rd == ra)
+	    {
+	      stack.store (pv_add_constant (regs[sp], si12), register_size (gdbarch, rd), regs[rd]);
+	    }
 	}
       else if ((insn & 0xff000000) == 0x27000000 /* stptr.d rd,sp,si14  */
 	       && rj == sp)
 	{
 	  prologue_end = cur_pc + insn_len;
+	  /* ra, fp, s0~s8 are saved by callee with sp as a base */
+	  if ((rd >= fp && rd <= fp + 9) || rd == ra)
+	    {
+	      stack.store (pv_add_constant (regs[sp], si14), register_size (gdbarch, rd), regs[rd]);
+	    }
 	}
       else if ((insn & 0xfe000000) == 0x14000000) /* lu12i.w rd,si20  */
 	{
@@ -189,6 +247,38 @@ loongarch_scan_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc,
   if (prologue_end == 0)
     prologue_end = cur_pc;
 
+  if (this_cache == NULL)
+    return prologue_end;
+
+  if (pv_is_register (regs[LOONGARCH_FP_REGNUM], LOONGARCH_SP_REGNUM))
+    {
+      /* Frame pointer is fp.  */
+      this_cache->framebase_reg = LOONGARCH_FP_REGNUM;
+      this_cache->framebase_offset = -regs[LOONGARCH_FP_REGNUM].k;
+    }
+  else if (pv_is_register (regs[LOONGARCH_SP_REGNUM], LOONGARCH_SP_REGNUM))
+    {
+      /* Try the stack pointer.  */
+      this_cache->framebase_reg = LOONGARCH_SP_REGNUM;
+      this_cache->framebase_offset = -regs[LOONGARCH_SP_REGNUM].k;
+    }
+  else
+    {
+      /* We're just out of luck.  We don't know where the frame is.  */
+      this_cache->framebase_reg = -1;
+      this_cache->framebase_offset = 0;
+    }
+
+  for (i = 0; i < LOONGARCH_USED_NUM_GREGSET; i++)
+    {
+      CORE_ADDR offset;
+
+      if (stack.find_reg (gdbarch, i, &offset))
+	{
+	  this_cache->saved_regs[i].set_addr (offset);
+	}
+    }
+
   return prologue_end;
 }
 
@@ -314,6 +404,20 @@ loongarch_next_pc (struct regcache *regcache, CORE_ADDR cur_pc)
       if (rj != 0)
 	next_pc = cur_pc + loongarch_decode_imm ("0:5|10:16<<2", insn, 1);
     }
+  else if ((insn & 0xfc000300) == 0x48000000)		/* bceqz cj, offs21  */
+    {
+      LONGEST cj = regcache_raw_get_signed (regcache,
+		     loongarch_decode_imm ("5:3", insn, 0) + LOONGARCH_FIRST_FCC_REGNUM);
+      if (cj == 0)
+	next_pc = cur_pc + loongarch_decode_imm ("0:5|10:16<<2", insn, 1);
+    }
+  else if ((insn & 0xfc000300) == 0x48000100)		/* bcnez cj, offs21  */
+    {
+      LONGEST cj = regcache_raw_get_signed (regcache,
+		     loongarch_decode_imm ("5:3", insn, 0) + LOONGARCH_FIRST_FCC_REGNUM);
+      if (cj != 0)
+	next_pc = cur_pc + loongarch_decode_imm ("0:5|10:16<<2", insn, 1);
+    }
   else if ((insn & 0xffff8000) == 0x002b0000)		/* syscall  */
     {
       if (tdep->syscall_next_pc != nullptr)
@@ -410,38 +514,157 @@ loongarch_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
   return align_down (addr, 16);
 }
 
+/* Analyze the function prologue for THIS_FRAME and populate the frame
+   cache CACHE.  */
+
+static void
+loongarch_analyze_prologue (const frame_info_ptr &this_frame,
+			    struct loongarch_frame_cache *cache)
+{
+  CORE_ADDR block_addr = get_frame_address_in_block (this_frame);
+  CORE_ADDR prologue_start = 0;
+  CORE_ADDR prologue_end = 0;
+  CORE_ADDR pc = get_frame_pc (this_frame);
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
+
+  cache->pc = pc;
+
+  /* Assume we do not find a frame.  */
+  cache->framebase_reg = -1;
+  cache->framebase_offset = 0;
+
+
+  if (find_pc_partial_function (block_addr, NULL, &prologue_start,
+				&prologue_end))
+    {
+      struct symtab_and_line sal = find_pc_line (prologue_start, 0);
+
+      if (sal.line == 0)
+	{
+	  /* No line info so use the current PC.  */
+	  prologue_end = pc;
+	}
+      else if (sal.end < prologue_end)
+	{
+	  if (sal.symtab != NULL && sal.symtab->language () == language_asm)
+	    {
+	      /* This sal.end usually cannot point to prologue_end correctly
+		 in asm file. */
+	      prologue_end = pc;
+	    }
+	  else
+	    {
+	      /* The next line begins after the prologue_end.  */
+	      prologue_end = sal.end;
+	    }
+	}
+
+    }
+  else
+    {
+      /* We're in the boondocks: we have no idea where the start of the
+	 function is.  */
+      return;
+    }
+
+  prologue_end = std::min (prologue_end, pc);
+  loongarch_scan_prologue (gdbarch, prologue_start, prologue_end, nullptr, cache);
+}
+
+/* Fill in *CACHE with information about the prologue of *THIS_FRAME.  */
+
+static void
+loongarch_frame_cache_1 (const frame_info_ptr &this_frame,
+			 struct loongarch_frame_cache *cache)
+{
+  CORE_ADDR unwound_fp;
+  int reg;
+
+  loongarch_analyze_prologue (this_frame, cache);
+
+  if (cache->framebase_reg == -1)
+    return;
+
+  unwound_fp = get_frame_register_unsigned (this_frame, cache->framebase_reg);
+  if (unwound_fp == 0)
+    return;
+
+  cache->prev_sp = unwound_fp;
+  cache->prev_sp += cache->framebase_offset;
+
+  /* Calculate actual addresses of saved registers using offsets
+     determined by loongarch_scan_prologue.  */
+  for (reg = 0; reg < gdbarch_num_regs (get_frame_arch (this_frame)); reg++)
+    if (cache->saved_regs[reg].is_addr ())
+      cache->saved_regs[reg].set_addr (cache->saved_regs[reg].addr ()
+				       + cache->prev_sp);
+
+  cache->func = get_frame_func (this_frame);
+
+  cache->available_p = 1;
+}
+
 /* Generate, or return the cached frame cache for frame unwinder.  */
 
-static struct trad_frame_cache *
+static struct loongarch_frame_cache *
 loongarch_frame_cache (const frame_info_ptr &this_frame, void **this_cache)
 {
-  struct trad_frame_cache *cache;
-  CORE_ADDR pc;
+  struct loongarch_frame_cache *cache;
 
-  if (*this_cache != nullptr)
-    return (struct trad_frame_cache *) *this_cache;
+  if (*this_cache != NULL)
+    return (struct loongarch_frame_cache *) *this_cache;
 
-  cache = trad_frame_cache_zalloc (this_frame);
+  cache = FRAME_OBSTACK_ZALLOC (struct loongarch_frame_cache);
+  cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
   *this_cache = cache;
 
-  trad_frame_set_reg_realreg (cache, LOONGARCH_PC_REGNUM, LOONGARCH_RA_REGNUM);
-
-  pc = get_frame_address_in_block (this_frame);
-  trad_frame_set_id (cache, frame_id_build_unavailable_stack (pc));
+  try
+    {
+      loongarch_frame_cache_1 (this_frame, cache);
+    }
+  catch (const gdb_exception_error &ex)
+    {
+      if (ex.error != NOT_AVAILABLE_ERROR)
+	throw;
+    }
 
   return cache;
 }
 
+/* Implement the "stop_reason" frame_unwind method.  */
+
+static enum unwind_stop_reason
+loongarch_frame_unwind_stop_reason (const frame_info_ptr &this_frame,
+				    void **this_cache)
+{
+  struct loongarch_frame_cache *cache
+    = loongarch_frame_cache (this_frame, this_cache);
+
+  if (!cache->available_p)
+    return UNWIND_UNAVAILABLE;
+
+  /* We've hit a wall, stop.  */
+  if (cache->prev_sp == 0)
+    return UNWIND_OUTERMOST;
+
+  return UNWIND_NO_REASON;
+}
+
 /* Implement the this_id callback for frame unwinder.  */
 
 static void
 loongarch_frame_this_id (const frame_info_ptr &this_frame, void **prologue_cache,
 			 struct frame_id *this_id)
 {
-  struct trad_frame_cache *info;
+  struct loongarch_frame_cache *cache
+    = loongarch_frame_cache (this_frame, prologue_cache);
 
-  info = loongarch_frame_cache (this_frame, prologue_cache);
-  trad_frame_get_id (info, this_id);
+  /* Our frame ID for a normal frame is the current function's starting
+     PC and the caller's SP when we were called.  */
+  if (!cache->available_p)
+    *this_id = frame_id_build_unavailable_stack (cache->func);
+  else
+    *this_id = frame_id_build (cache->prev_sp, cache->func);
 }
 
 /* Implement the prev_register callback for frame unwinder.  */
@@ -450,17 +673,55 @@ static struct value *
 loongarch_frame_prev_register (const frame_info_ptr &this_frame,
 			       void **prologue_cache, int regnum)
 {
-  struct trad_frame_cache *info;
+  struct loongarch_frame_cache *cache
+    = loongarch_frame_cache (this_frame, prologue_cache);
+
+  /* If we are asked to unwind the PC, then we need to return the RA
+     instead.  The prologue may save PC, but it will point into this
+     frame's prologue, not the previou frame's resume location.  */
+  if (regnum == LOONGARCH_PC_REGNUM)
+    {
+      CORE_ADDR ra;
+      ra = frame_unwind_register_unsigned (this_frame, LOONGARCH_RA_REGNUM);
+
+      return frame_unwind_got_constant (this_frame, regnum, ra);
+    }
+
+  /* SP is generally not saved to the stack, but this frame is
+     identified by the next frame's stack pointer at the time of the
+     call.  The value was already reconstructed into PREV_SP.  */
+  /*
+	addi.d          $sp, $sp, -32
+	st.d            $ra, $sp, 24
+	st.d            $fp, $sp, 16
+	addi.d          $fp, $sp, 32
+
+	+->+----------+
+	|  | saved ra |
+	|  | saved fp |
+	|  |          |
+	|  |          |
+	|  +----------+  <- Previous SP == FP
+	|  | saved ra |
+	+--| saved fp |
+	   |          |
+	   |          |
+	   +----------+   <- SP
+			*/
+
+  if (regnum == LOONGARCH_SP_REGNUM)
+    return frame_unwind_got_constant (this_frame, regnum, cache->prev_sp);
+
+  return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum);
 
-  info = loongarch_frame_cache (this_frame, prologue_cache);
-  return trad_frame_get_register (info, this_frame, regnum);
 }
 
+/* LoongArch prologue unwinder.  */
 static const struct frame_unwind_legacy loongarch_frame_unwind (
   "loongarch prologue",
   /*.type	   =*/NORMAL_FRAME,
   /*.unwinder_class=*/FRAME_UNWIND_ARCH,
-  /*.stop_reason   =*/default_frame_unwind_stop_reason,
+  /*.stop_reason   =*/loongarch_frame_unwind_stop_reason,
   /*.this_id	   =*/loongarch_frame_this_id,
   /*.prev_register =*/loongarch_frame_prev_register,
   /*.unwind_data   =*/nullptr,
@@ -1879,7 +2140,7 @@ loongarch_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   set_gdbarch_frame_align (gdbarch, loongarch_frame_align);
 
   /* Breakpoint manipulation.  */
-  set_gdbarch_software_single_step (gdbarch, loongarch_software_single_step);
+  set_gdbarch_get_next_pcs (gdbarch, loongarch_software_single_step);
   set_gdbarch_breakpoint_kind_from_pc (gdbarch, loongarch_breakpoint::kind_from_pc);
   set_gdbarch_sw_breakpoint_from_kind (gdbarch, loongarch_breakpoint::bp_from_kind);
   set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1);
@@ -2405,9 +2666,7 @@ loongarch_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
   return ret;
 }
 
-void _initialize_loongarch_tdep ();
-void
-_initialize_loongarch_tdep ()
+INIT_GDB_FILE (loongarch_tdep)
 {
   gdbarch_register (bfd_arch_loongarch, loongarch_gdbarch_init, nullptr);
 }