gdb: add target_ops::supports_displaced_step

[deliverable/binutils-gdb.git] / gdb / trad-frame.c

diff --git a/gdb/trad-frame.c b/gdb/trad-frame.c
index 86498e00f3dcf63e1892bcd75fe1e5986c140701..a6a84790a99208f2d20939c25b186267e07307a8 100644 (file)
--- a/gdb/trad-frame.c
+++ b/gdb/trad-frame.c
@@ -1,6 +1,6 @@
 /* Traditional frame unwind support, for GDB the GNU Debugger.
 
-   Copyright (C) 2003-2004, 2007-2012 Free Software Foundation, Inc.
+   Copyright (C) 2003-2020 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -22,7 +22,9 @@
 #include "trad-frame.h"
 #include "regcache.h"
 #include "frame-unwind.h"
+#include "target.h"
 #include "value.h"
+#include "gdbarch.h"
 
 struct trad_frame_cache
 {
@@ -43,6 +45,31 @@ trad_frame_cache_zalloc (struct frame_info *this_frame)
   return this_trad_cache;
 }
 
+/* See trad-frame.h.  */
+
+void
+trad_frame_reset_saved_regs (struct gdbarch *gdbarch,
+                            struct trad_frame_saved_reg *regs)
+{
+  int numregs = gdbarch_num_cooked_regs (gdbarch);
+  for (int regnum = 0; regnum < numregs; regnum++)
+    {
+      regs[regnum].realreg = regnum;
+      regs[regnum].addr = -1;
+    }
+}
+
+struct trad_frame_saved_reg *
+trad_frame_alloc_saved_regs (struct gdbarch *gdbarch)
+{
+  int numregs = gdbarch_num_cooked_regs (gdbarch);
+  struct trad_frame_saved_reg *this_saved_regs
+    = FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg);
+
+  trad_frame_reset_saved_regs (gdbarch, this_saved_regs);
+  return this_saved_regs;
+}
+
 /* A traditional frame is unwound by analysing the function prologue
    and using the information gathered to track registers.  For
    non-optimized frames, the technique is reliable (just need to check
@@ -51,18 +78,9 @@ trad_frame_cache_zalloc (struct frame_info *this_frame)
 struct trad_frame_saved_reg *
 trad_frame_alloc_saved_regs (struct frame_info *this_frame)
 {
-  int regnum;
   struct gdbarch *gdbarch = get_frame_arch (this_frame);
-  int numregs = gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
-  struct trad_frame_saved_reg *this_saved_regs
-    = FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg);
 
-  for (regnum = 0; regnum < numregs; regnum++)
-    {
-      this_saved_regs[regnum].realreg = regnum;
-      this_saved_regs[regnum].addr = -1;
-    }      
-  return this_saved_regs;
+  return trad_frame_alloc_saved_regs (gdbarch);
 }
 
 enum { TF_REG_VALUE = -1, TF_REG_UNKNOWN = -2 };
@@ -98,6 +116,26 @@ trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
   this_saved_regs[regnum].addr = val;
 }
 
+/* See trad-frame.h.  */
+
+void
+trad_frame_set_realreg (struct trad_frame_saved_reg this_saved_regs[],
+                       int regnum, int realreg)
+{
+  this_saved_regs[regnum].realreg = realreg;
+  this_saved_regs[regnum].addr = -1;
+}
+
+/* See trad-frame.h.  */
+
+void
+trad_frame_set_addr (struct trad_frame_saved_reg this_saved_regs[],
+                    int regnum, CORE_ADDR addr)
+{
+  this_saved_regs[regnum].realreg = regnum;
+  this_saved_regs[regnum].addr = addr;
+}
+
 void
 trad_frame_set_reg_value (struct trad_frame_cache *this_trad_cache,
                          int regnum, LONGEST val)
@@ -111,15 +149,70 @@ void
 trad_frame_set_reg_realreg (struct trad_frame_cache *this_trad_cache,
                            int regnum, int realreg)
 {
-  this_trad_cache->prev_regs[regnum].realreg = realreg;
-  this_trad_cache->prev_regs[regnum].addr = -1;
+  trad_frame_set_realreg (this_trad_cache->prev_regs, regnum, realreg);
 }
 
 void
 trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache,
                         int regnum, CORE_ADDR addr)
 {
-  this_trad_cache->prev_regs[regnum].addr = addr;
+  trad_frame_set_addr (this_trad_cache->prev_regs, regnum, addr);
+}
+
+void
+trad_frame_set_reg_regmap (struct trad_frame_cache *this_trad_cache,
+                          const struct regcache_map_entry *regmap,
+                          CORE_ADDR addr, size_t size)
+{
+  struct gdbarch *gdbarch = get_frame_arch (this_trad_cache->this_frame);
+  int offs = 0, count;
+
+  for (; (count = regmap->count) != 0; regmap++)
+    {
+      int regno = regmap->regno;
+      int slot_size = regmap->size;
+
+      if (slot_size == 0 && regno != REGCACHE_MAP_SKIP)
+       slot_size = register_size (gdbarch, regno);
+
+      if (offs + slot_size > size)
+       break;
+
+      if (regno == REGCACHE_MAP_SKIP)
+       offs += count * slot_size;
+      else
+       for (; count--; regno++, offs += slot_size)
+         {
+           /* Mimic the semantics of regcache::transfer_regset if a
+              register slot's size does not match the size of a
+              register.
+
+              If a register slot is larger than a register, assume
+              the register's value is stored in the first N bytes of
+              the slot and ignore the remaining bytes.
+
+              If the register slot is smaller than the register,
+              assume that the slot contains the low N bytes of the
+              register's value.  Since trad_frame assumes that
+              registers stored by address are sized according to the
+              register, read the low N bytes and zero-extend them to
+              generate a register value.  */
+           if (slot_size >= register_size (gdbarch, regno))
+             trad_frame_set_reg_addr (this_trad_cache, regno, addr + offs);
+           else
+             {
+               enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+               gdb_byte buf[slot_size];
+
+               if (target_read_memory (addr + offs, buf, sizeof buf) == 0)
+                 {
+                   LONGEST val
+                     = extract_unsigned_integer (buf, sizeof buf, byte_order);
+                   trad_frame_set_reg_value (this_trad_cache, regno, val);
+                 }
+             }
+         }
+    }
 }
 
 void