From: Christophe Lyon <christophe.lyon@linaro.org>
Date: Wed, 14 Apr 2021 14:22:34 +0000 (+0000)
Subject: ARM/FDPIC: Add support for GDB call command
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=82934b09cd4edee8ab0c005c3b4b25bee7c51910;p=thirdparty%2Fbinutils-gdb.git

ARM/FDPIC: Add support for GDB call command

2021-04-14  Mickael Guene  <mickael.guene@st.com>
	Christophe Lyon  <christophe.lyon@st.com>

	* gdb/arm-tdep.c (arm_push_dummy_call): Handle FDPIC case.
	* gdb/arm-tdep.h (fdpic_find_global_pointer): Declare.
	* gdb/solib-fdpic.c (fdpic_find_global_pointer): New.
---

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 4b2130a4ead..9e8b382f66d 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -44,6 +44,7 @@
 #include "target-descriptions.h"
 #include "user-regs.h"
 #include "observer.h"
+#include "infcall.h"
 
 #include "arm-tdep.h"
 #include "gdb/sim-arm.h"
@@ -3749,6 +3750,14 @@ arm_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
       si = pop_stack_item (si);
     }
 
+  if (gdbarch_tdep (gdbarch)->is_fdpic)
+  {
+    CORE_ADDR func_addr = find_function_addr (function, NULL);
+
+    regcache_cooked_write_unsigned (regcache, 9,
+				    fdpic_find_global_pointer (func_addr));
+  }
+
   /* Finally, update teh SP register.  */
   regcache_cooked_write_unsigned (regcache, ARM_SP_REGNUM, sp);
 
diff --git a/gdb/arm-tdep.h b/gdb/arm-tdep.h
index d32e6561eb8..8be97652f15 100644
--- a/gdb/arm-tdep.h
+++ b/gdb/arm-tdep.h
@@ -359,5 +359,6 @@ extern struct target_desc *tdesc_arm_with_neon;
 /* FDPIC structure and api.  */
 extern struct target_so_ops fdpic_so_ops;
 extern CORE_ADDR fdpic_fetch_objfile_link_map (struct objfile *objfile);
+extern CORE_ADDR fdpic_find_global_pointer (CORE_ADDR addr);
 
 #endif /* arm-tdep.h */
diff --git a/gdb/solib-fdpic.c b/gdb/solib-fdpic.c
index a0b7db94c73..497742d00e8 100644
--- a/gdb/solib-fdpic.c
+++ b/gdb/solib-fdpic.c
@@ -598,6 +598,36 @@ enable_break2 (void)
   return 0;
 }
 
+/* Exported functions.  */
+/* Find the global pointer for the given function address ADDR.  */
+CORE_ADDR
+fdpic_find_global_pointer (CORE_ADDR addr)
+{
+  struct so_list *so;
+
+  so = master_so_list ();
+  while (so)
+    {
+      int seg;
+      struct elf32_fdpic_loadmap *map;
+
+      map = so->lm_info->map;
+
+      for (seg = 0; seg < map->nsegs; seg++)
+	{
+	  if (map->segs[seg].addr <= addr
+	      && addr < map->segs[seg].addr + map->segs[seg].p_memsz)
+	    return so->lm_info->got_value;
+	}
+
+      so = so->next;
+    }
+
+  /* Didn't find it in any of the shared objects.
+     So assume it's in the main executable.  */
+  return main_got ();
+}
+
 /* Shared object operations.  */
 static int
 fdpic_in_dynsym_resolve_code (CORE_ADDR pc)