gcc-source: Add MicroBlaze DWARF exception support

This resolves some issues with unwind support needed for pthread.

Signed-off-by: Nathan Rossi <nathan@nathanrossi.com>

2 files changed, 168 insertions, 0 deletions

diff --git a/recipes-microblaze/gcc/files/Enable-DWARF-exception-handling-support.patch b/recipes-microblaze/gcc/files/Enable-DWARF-exception-handling-support.patch
new file mode 100644
index 00000000..4a16d2f7
--- /dev/null
+++ b/recipes-microblaze/gcc/files/Enable-DWARF-exception-handling-support.patch
@@ -0,0 +1,167 @@
+From 7a9ef06991e293be4d5ef2be1d9716a31f90447e Mon Sep 17 00:00:00 2001
+From: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
+Date: Mon, 18 Jun 2012 20:18:13 +0200
+Subject: [PATCH] Enable DWARF exception handling support.
+
+Changelog
+
+2013-03-18  Edgar E. Iglesias <edgar.iglesias@xilinx.com>
+            David Holsgrove <david.holsgrove@xilinx.com>
+
+ * common/config/microblaze/microblaze-common.c: Remove
+   TARGET_EXCEPT_UNWIND_INFO definition.
+ * config/microblaze/microblaze-protos.h: Add
+   microblaze_eh_return prototype.
+ * gcc/config/microblaze/microblaze.c: (microblaze_must_save_register,
+   microblaze_expand_epilogue, microblaze_return_addr): Handle
+   calls_eh_return
+   (microblaze_eh_return): New function.
+ * gcc/config/microblaze/microblaze.h: Define RETURN_ADDR_OFFSET,
+   EH_RETURN_DATA_REGNO, MB_EH_STACKADJ_REGNUM, EH_RETURN_STACKADJ_RTX,
+   ASM_PREFERRED_EH_DATA_FORMAT
+ * gcc/config/microblaze/microblaze.md: Define eh_return pattern.
+
+Signed-off-by: David Holsgrove <david.holsgrove@xilinx.com>
+Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
+---
+ gcc/common/config/microblaze/microblaze-common.c |  3 ---
+ gcc/config/microblaze/microblaze-protos.h        |  1 +
+ gcc/config/microblaze/microblaze.c               | 29 ++++++++++++++++++++----
+ gcc/config/microblaze/microblaze.h               | 15 ++++++++++++
+ gcc/config/microblaze/microblaze.md              | 11 +++++++++
+ 5 files changed, 52 insertions(+), 7 deletions(-)
+
+diff --git a/gcc/common/config/microblaze/microblaze-common.c b/gcc/common/config/microblaze/microblaze-common.c
+index f369bc58d1..0e1bdc4f58 100644
+--- a/gcc/common/config/microblaze/microblaze-common.c
++++ b/gcc/common/config/microblaze/microblaze-common.c
+@@ -37,7 +37,4 @@ static const struct default_options microblaze_option_optimization_table[] =
+ #undef  TARGET_OPTION_OPTIMIZATION_TABLE
+ #define TARGET_OPTION_OPTIMIZATION_TABLE microblaze_option_optimization_table
+ 
+-#undef TARGET_EXCEPT_UNWIND_INFO
+-#define TARGET_EXCEPT_UNWIND_INFO  sjlj_except_unwind_info
+-
+ struct gcc_targetm_common targetm_common = TARGETM_COMMON_INITIALIZER;
+diff --git a/gcc/config/microblaze/microblaze-protos.h b/gcc/config/microblaze/microblaze-protos.h
+index 1cfaf08c1c..cc3b4619c4 100644
+--- a/gcc/config/microblaze/microblaze-protos.h
++++ b/gcc/config/microblaze/microblaze-protos.h
+@@ -57,6 +57,7 @@ extern bool microblaze_tls_referenced_p (rtx);
+ extern int symbol_mentioned_p (rtx);
+ extern int label_mentioned_p (rtx);
+ extern bool microblaze_cannot_force_const_mem (machine_mode, rtx);
++extern void microblaze_eh_return (rtx op0);
+ #endif  /* RTX_CODE */
+ 
+ /* Declare functions in microblaze-c.c.  */
+diff --git a/gcc/config/microblaze/microblaze.c b/gcc/config/microblaze/microblaze.c
+index baff67a89c..71f1495bae 100644
+--- a/gcc/config/microblaze/microblaze.c
++++ b/gcc/config/microblaze/microblaze.c
+@@ -1924,6 +1924,11 @@ microblaze_must_save_register (int regno)
+   if (frame_pointer_needed && (regno == HARD_FRAME_POINTER_REGNUM))
+     return 1;
+ 
++  if (crtl->calls_eh_return
++      && regno == MB_ABI_SUB_RETURN_ADDR_REGNUM) {
++    return 1;
++  }
++
+   if (!crtl->is_leaf)
+     {
+       if (regno == MB_ABI_SUB_RETURN_ADDR_REGNUM)
+@@ -1951,6 +1956,13 @@ microblaze_must_save_register (int regno)
+        return 1;
+     }
+ 
++  if (crtl->calls_eh_return
++      && (regno == EH_RETURN_DATA_REGNO (0)
++          || regno == EH_RETURN_DATA_REGNO (1)))
++    {
++      return 1;
++    }
++
+   return 0;
+ }
+ 
+@@ -3027,6 +3039,12 @@ microblaze_expand_epilogue (void)
+       emit_insn (gen_addsi3 (stack_pointer_rtx, stack_pointer_rtx, fsiz_rtx));
+     }
+ 
++  if (crtl->calls_eh_return)
++    emit_insn (gen_addsi3 (stack_pointer_rtx,
++                           stack_pointer_rtx,
++                           gen_rtx_REG (SImode,
++                                            MB_EH_STACKADJ_REGNUM)));
++
+   emit_jump_insn (gen_return_internal (gen_rtx_REG (Pmode, GP_REG_FIRST +
+                                                    MB_ABI_SUB_RETURN_ADDR_REGNUM)));
+ }
+@@ -3324,10 +3342,13 @@ microblaze_return_addr (int count, rtx frame ATTRIBUTE_UNUSED)
+   if (count != 0)
+     return NULL_RTX;
+ 
+-  return gen_rtx_PLUS (Pmode,
+-                      get_hard_reg_initial_val (Pmode,
+-                                                MB_ABI_SUB_RETURN_ADDR_REGNUM),
+-                      GEN_INT (8));
++  return get_hard_reg_initial_val (Pmode,
++                                   MB_ABI_SUB_RETURN_ADDR_REGNUM);
++}
++
++void microblaze_eh_return (rtx op0)
++{
++  emit_insn (gen_movsi(gen_rtx_MEM(Pmode, stack_pointer_rtx), op0));
+ }
+ 
+ /* Queue an .ident string in the queue of top-level asm statements.
+diff --git a/gcc/config/microblaze/microblaze.h b/gcc/config/microblaze/microblaze.h
+index e115c42839..4b0662024b 100644
+--- a/gcc/config/microblaze/microblaze.h
++++ b/gcc/config/microblaze/microblaze.h
+@@ -184,6 +184,21 @@ extern enum pipeline_type microblaze_pipe;
+ #define INCOMING_RETURN_ADDR_RTX                       \
+   gen_rtx_REG (VOIDmode, GP_REG_FIRST + MB_ABI_SUB_RETURN_ADDR_REGNUM)
+ 
++/* Specifies the offset from INCOMING_RETURN_ADDR_RTX and the actual return PC.  */
++#define RETURN_ADDR_OFFSET (8)
++
++/* Describe how we implement __builtin_eh_return.  */
++#define EH_RETURN_DATA_REGNO(N) (((N) < 2) ? MB_ABI_FIRST_ARG_REGNUM + (N) : INVALID_REGNUM)
++
++#define MB_EH_STACKADJ_REGNUM  MB_ABI_INT_RETURN_VAL2_REGNUM
++#define EH_RETURN_STACKADJ_RTX  gen_rtx_REG (Pmode, MB_EH_STACKADJ_REGNUM)
++
++/* Select a format to encode pointers in exception handling data.  CODE
++   is 0 for data, 1 for code labels, 2 for function pointers.  GLOBAL is
++   true if the symbol may be affected by dynamic relocations.  */
++#define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL) \
++  ((flag_pic || GLOBAL) ? DW_EH_PE_aligned : DW_EH_PE_absptr)
++
+ /* Use DWARF 2 debugging information by default.  */
+ #define DWARF2_DEBUGGING_INFO
+ #define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG
+diff --git a/gcc/config/microblaze/microblaze.md b/gcc/config/microblaze/microblaze.md
+index 85776237c1..b388d25741 100644
+--- a/gcc/config/microblaze/microblaze.md
++++ b/gcc/config/microblaze/microblaze.md
+@@ -2324,4 +2324,15 @@
+   (set_attr "mode"      "SI")
+   (set_attr "length"    "4")])
+ 
++; This is used in compiling the unwind routines.
++(define_expand "eh_return"
++  [(use (match_operand 0 "general_operand" ""))]
++  ""
++  "
++{
++  microblaze_eh_return(operands[0]);
++  DONE;
++}")
++
+ (include "sync.md")
++
+-- 
+2.9.3
+
diff --git a/recipes-microblaze/gcc/gcc-source_6.%.bbappend b/recipes-microblaze/gcc/gcc-source_6.%.bbappend
index 76b4f60c..b3e8c071 100644
--- a/recipes-microblaze/gcc/gcc-source_6.%.bbappend
+++ b/recipes-microblaze/gcc/gcc-source_6.%.bbappend
@@ -4,5 +4,6 @@ FILESEXTRAPATHS_append := "${THISDIR}/files:"
 SRC_URI_append = " \
                 file://microblaze.md-Improve-adddi3-and-subdi3-insn-definit.patch \
                 file://gcc-config-microblaze-Make-r21-fixed-due-to-Linux-AB.patch \
+                file://Enable-DWARF-exception-handling-support.patch \
                 "