From 5a39451f34be9b6ca98b3460bf40d879d6ee61a5 Mon Sep 17 00:00:00 2001
From: Charles Baylis <charles.baylis@linaro.org>
Date: Thu, 24 Mar 2016 20:43:25 +0000
Subject: [PATCH] PR69770 -mlong-calls does not affect calls to __gnu_mcount_nc
 generated by -pg

gcc/ChangeLog:

2016-03-24  Charles Baylis  <charles.baylis@linaro.org>

        * config/arm/arm-protos.h (arm_emit_long_call_profile): New function.
        * config/arm/arm.c (arm_emit_long_call_profile_insn): New function.
        (arm_expand_prologue): Likewise.
        (thumb1_expand_prologue): Likewise.
        (arm_output_long_call_to_profile_func): Likewise.
        (arm_emit_long_call_profile): Likewise.
        * config/arm/arm.h: (ASM_OUTPUT_REG_PUSH) Update comment.
        * config/arm/arm.md (arm_long_call_profile): New pattern.
        * config/arm/bpabi.h (ARM_FUNCTION_PROFILER_SUPPORTS_LONG_CALLS): New
	define.
        * config/arm/thumb1.md (thumb1_long_call_profile): New pattern.
        * config/arm/unspecs.md (unspecv): Add VUNSPEC_LONG_CALL_PROFILE.

gcc/testsuite/ChangeLog:

2016-03-24  Charles Baylis  <charles.baylis@linaro.org>

        * gcc.target/arm/pr69770.c: New test.

Change-Id: I9b8de01fea083f17f729c3801f83174bedb3b0c6

diff --git a/gcc/config/arm/arm-protos.h b/gcc/config/arm/arm-protos.h
index 0083673..324c9f4 100644
--- a/gcc/config/arm/arm-protos.h
+++ b/gcc/config/arm/arm-protos.h
@@ -343,6 +343,7 @@ extern void arm_register_target_pragmas (void);
 extern void arm_cpu_cpp_builtins (struct cpp_reader *);
 
 extern bool arm_is_constant_pool_ref (rtx);
+void arm_emit_long_call_profile ();
 
 /* Flags used to identify the presence of processor capabilities.  */
 
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index c868490..040b255 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -21426,6 +21426,22 @@ output_probe_stack_range (rtx reg1, rtx reg2)
   return "";
 }
 
+static void
+arm_emit_long_call_profile_insn ()
+{
+  rtx sym_ref = gen_rtx_SYMBOL_REF (Pmode, "__gnu_mcount_nc");
+  /* if movt/movw are not available, use a constant pool */
+  if (!arm_arch_thumb2)
+  {
+    sym_ref = force_const_mem(Pmode, sym_ref);
+  }
+  rtvec vec = gen_rtvec (1, sym_ref);
+  rtx tmp =
+    gen_rtx_UNSPEC_VOLATILE (VOIDmode, vec, VUNSPEC_LONG_CALL_PROFILE);
+  emit_insn (tmp);
+}
+
+
 /* Generate the prologue instructions for entry into an ARM or Thumb-2
    function.  */
 void
@@ -21789,6 +21805,10 @@ arm_expand_prologue (void)
       arm_load_pic_register (mask);
     }
 
+  if (crtl->profile && TARGET_LONG_CALLS
+      && ARM_FUNCTION_PROFILER_SUPPORTS_LONG_CALLS)
+    arm_emit_long_call_profile_insn ();
+
   /* If we are profiling, make sure no instructions are scheduled before
      the call to mcount.  Similarly if the user has requested no
      scheduling in the prolog.  Similarly if we want non-call exceptions
@@ -24985,6 +25005,10 @@ thumb1_expand_prologue (void)
   if (frame_pointer_needed)
     thumb_set_frame_pointer (offsets);
 
+  if (crtl->profile && TARGET_LONG_CALLS
+      && ARM_FUNCTION_PROFILER_SUPPORTS_LONG_CALLS)
+    arm_emit_long_call_profile_insn ();
+
   /* If we are profiling, make sure no instructions are scheduled before
      the call to mcount.  Similarly if the user has requested no
      scheduling in the prolog.  Similarly if we want non-call exceptions
@@ -30289,4 +30313,70 @@ arm_sched_fusion_priority (rtx_insn *insn, int max_pri,
   return;
 }
 
+static void
+arm_output_long_call_to_profile_func (rtx * operands, bool push_scratch)
+{
+  /* operands[0] is the address of the __gnu_mcount_nc function
+     operands[1] is the scratch register we use to load that address */
+  if (push_scratch)
+    output_asm_insn ("push\t{%1}", operands);
+  output_asm_insn ("push\t{lr}", operands);
+  if (GET_CODE (operands[0]) == SYMBOL_REF)
+    {
+      output_asm_insn ("movw\t%1, #:lower16:%c0", operands);
+      output_asm_insn ("movt\t%1, #:upper16:%c0", operands);
+    }
+  else
+    {
+      output_asm_insn ("ldr\t%1, %0", operands);
+    }
+  if (!arm_arch5)
+    {
+      output_asm_insn ("mov\tlr, pc", operands);
+      output_asm_insn ("mov\tpc, %1", operands);
+    }
+  else
+    output_asm_insn ("blx\t%1", operands);
+  if (push_scratch)
+    output_asm_insn ("pop\t{%1}", operands);
+}
+
+void
+arm_emit_long_call_profile()
+{
+  rtx alcp = NULL;
+  rtx operands[2];
+  bool push_scratch;
+  /* find the arm_long_call_profile */
+  for (rtx_insn * insn = get_insns (); insn; insn = NEXT_INSN (insn))
+    {
+      if (NOTE_P (insn) && NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
+	break;
+      if (INSN_CODE (insn) == CODE_FOR_arm_long_call_profile
+	  || INSN_CODE (insn) == CODE_FOR_thumb1_long_call_profile)
+	{
+	  alcp = PATTERN (insn);
+	  break;
+	}
+    }
+  gcc_assert (alcp);
+
+  operands[0] = XEXP (XEXP (alcp, 0), 0);
+  if (TARGET_32BIT)
+    {
+      operands[1] = gen_rtx_REG (SImode, IP_REGNUM);
+      push_scratch = false;
+    }
+  else
+    {
+      /* for nested functions, we can set push_scratch to false, since
+	 final.c:profile_function.c and ASM_OUTPUT_REG_PUSH preserve it as
+         part of the sequence to preserve ip across the call to the 
+         profiling function. */
+      operands[1] = gen_rtx_REG (SImode, R0_REGNUM + 7);
+      push_scratch = !IS_NESTED (arm_current_func_type ());
+    }
+  arm_output_long_call_to_profile_func (operands, push_scratch);
+}
+
 #include "gt-arm.h"
diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h
index 6352140..44f1c64 100644
--- a/gcc/config/arm/arm.h
+++ b/gcc/config/arm/arm.h
@@ -2044,7 +2044,9 @@ extern int making_const_table;
    that ASM_OUTPUT_REG_PUSH will be matched with ASM_OUTPUT_REG_POP, and
    that r7 isn't used by the function profiler, so we can use it as a
    scratch reg.  WARNING: This isn't safe in the general case!  It may be
-   sensitive to future changes in final.c:profile_function.  */
+   sensitive to future changes in final.c:profile_function. This is also
+   relied on in arm_emit_long_call_profile() which assumes r7 can be
+   used as a scratch register to load the address of the function profiler.  */
 #define ASM_OUTPUT_REG_PUSH(STREAM, REGNO)		\
   do							\
     {							\
diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md
index 47171b9..beb44d5 100644
--- a/gcc/config/arm/arm.md
+++ b/gcc/config/arm/arm.md
@@ -11424,6 +11424,15 @@
   DONE;
 })
 
+(define_insn "arm_long_call_profile"
+  [(unspec_volatile [(match_operand:SI 0 "general_operand" "ji,m")
+                    ] VUNSPEC_LONG_CALL_PROFILE)]
+  "TARGET_32BIT"
+  "%@ arm_long_call_profile"
+  [(set_attr "arm_pool_range" "*,4096")
+   (set_attr "arm_neg_pool_range" "*,4084")]
+)
+
 ;; Vector bits common to IWMMXT and Neon
 (include "vec-common.md")
 ;; Load the Intel Wireless Multimedia Extension patterns
diff --git a/gcc/config/arm/bpabi.h b/gcc/config/arm/bpabi.h
index 5d6c4ed..7acf66b 100644
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -174,11 +174,18 @@
 
 #undef  NO_PROFILE_COUNTERS
 #define NO_PROFILE_COUNTERS 1
+#undef  ARM_FUNCTION_PROFILER_SUPPORTS_LONG_CALLS
+#define ARM_FUNCTION_PROFILER_SUPPORTS_LONG_CALLS 1
 #undef  ARM_FUNCTION_PROFILER
 #define ARM_FUNCTION_PROFILER(STREAM, LABELNO)  			\
 {									\
-  fprintf (STREAM, "\tpush\t{lr}\n");					\
-  fprintf (STREAM, "\tbl\t__gnu_mcount_nc\n");				\
+  if (TARGET_LONG_CALLS)						\
+  { 									\
+    arm_emit_long_call_profile();					\
+  } else {								\
+    fprintf (STREAM, "\tpush\t{lr}\n");					\
+    fprintf (STREAM, "\tbl\t__gnu_mcount_nc\n");			\
+  }									\
 }
 
 #undef SUBTARGET_FRAME_POINTER_REQUIRED
diff --git a/gcc/config/arm/thumb1.md b/gcc/config/arm/thumb1.md
index 072ed4d..9b1de5f 100644
--- a/gcc/config/arm/thumb1.md
+++ b/gcc/config/arm/thumb1.md
@@ -1798,7 +1798,7 @@
   [(unspec_volatile [(match_operand:SI 0 "s_register_operand" "l")]
 		    VUNSPEC_EH_RETURN)
    (clobber (match_scratch:SI 1 "=&l"))]
-  "TARGET_THUMB1"
+  "TARGET_THUMB1 && 0"
   "#"
   "&& reload_completed"
   [(const_int 0)]
@@ -1809,4 +1809,13 @@
   }"
   [(set_attr "type" "mov_reg")]
 )
+
+(define_insn "thumb1_long_call_profile"
+  [(unspec_volatile [(match_operand:SI 0 "general_operand" "j,m")
+                    ] VUNSPEC_LONG_CALL_PROFILE)]
+  "TARGET_THUMB1"
+  "%@ thumb1_long_call_profile"
+  [(set_attr "pool_range" "1018")]
+)
+
 
diff --git a/gcc/config/arm/unspecs.md b/gcc/config/arm/unspecs.md
index 5744c62..d7ddc3a 100644
--- a/gcc/config/arm/unspecs.md
+++ b/gcc/config/arm/unspecs.md
@@ -148,6 +148,7 @@
   VUNSPEC_GET_FPSCR	; Represent fetch of FPSCR content.
   VUNSPEC_SET_FPSCR	; Represent assign of FPSCR content.
   VUNSPEC_PROBE_STACK_RANGE ; Represent stack range probing.
+  VUNSPEC_LONG_CALL_PROFILE ; Represent a long call to profile function
 ])
 
 ;; Enumerators for NEON unspecs.
diff --git a/gcc/testsuite/gcc.target/arm/pr69770.c b/gcc/testsuite/gcc.target/arm/pr69770.c
new file mode 100644
index 0000000..61e5c6d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/pr69770.c
@@ -0,0 +1,9 @@
+/* { dg-do compile } */
+/* { dg-options "-pg -mlong-calls" } */
+
+extern void g(void);
+
+int f() { g(); return 0; }
+
+/* { dg-final { scan-assembler-not "bl\[ \t\]+__gnu_mcount_nc" } } */
+/* { dg-final { scan-assembler "__gnu_mcount_nc" } } */
-- 
1.9.1

