path: root/0002-Finish-CLIC-support-resolving-patch-merge-error-and-.patch

From 96fded3b45d93f306e86d9529b8ae3ff7f012088 Mon Sep 17 00:00:00 2001
From: Jim Wilson <jimw@sifive.com>
Date: Thu, 28 Feb 2019 12:09:52 -0800
Subject: [PATCH 2/3] Finish CLIC support, resolving patch merge error and
 adding missing patch.

---
 gcc/config/riscv/riscv.c                      | 124 ++++++++++--------
 gcc/config/riscv/riscv.md                     |   3 +-
 .../riscv/interrupt-conflict-mode.c           |   2 +-
 gcc/testsuite/gcc.target/riscv/stack-swap-1.c |   3 +-
 4 files changed, 69 insertions(+), 63 deletions(-)

diff --git a/gcc/config/riscv/riscv.c b/gcc/config/riscv/riscv.c
index d90715cca23..0dcfec1974d 100644
--- a/gcc/config/riscv/riscv.c
+++ b/gcc/config/riscv/riscv.c
@@ -96,7 +96,7 @@ enum riscv_address_type {
 };
 
 /* Information about a function's frame layout.  */
-struct GTY(())  riscv_frame_info {
+struct GTY(()) riscv_frame_info {
   /* The size of the frame in bytes.  */
   HOST_WIDE_INT total_size;
 
@@ -127,7 +127,18 @@ enum riscv_privilege_levels {
   UNKNOWN_MODE, USER_MODE, SUPERVISOR_MODE, MACHINE_MODE
 };
 
-struct GTY(())  machine_function {
+struct GTY(()) riscv_interrupt_flags {
+  /* For an interrupt handler, indicates the privilege level.  */
+  enum riscv_privilege_levels interrupt_mode : 2;
+  /* True if current function is an SiFive CLIC preemptible interrupt
+     function.  */
+  bool sifive_clic_preemptible_p : 1;
+  /* True if current function is an SiFive CLIC stack swap interrupt
+     function.  */
+  bool sifive_clic_stack_swap_p : 1;
+};
+
+struct GTY(()) machine_function {
   /* The number of extra stack bytes taken up by register varargs.
      This area is allocated by the callee at the very top of the frame.  */
   int varargs_size;
@@ -137,14 +148,8 @@ struct GTY(())  machine_function {
 
   /* True if current function is an interrupt function.  */
   bool interrupt_handler_p;
-  /* For an interrupt handler, indicates the privilege level.  */
-  enum riscv_privilege_levels interrupt_mode;
-  /* True if current function is an SiFive CLIC preemptible interrupt
-     function.  */
-  bool sifive_clic_preemptible_p;
-  /* True if current function is an SiFive CLIC stack swap interrupt
-     function.  */
-  bool sifive_clic_stack_swap_p;
+  /* For an interrupt handler, hold various argument flag bits.  */
+  struct riscv_interrupt_flags interrupt_flags;
 
   /* True if attributes on current function have been checked.  */
   bool attributes_checked_p;
@@ -3233,11 +3238,8 @@ riscv_print_operand (FILE *file, rtx op, int letter)
 		case MCAUSE_REGNUM:
 		  reg_name = "mcause";
 		  break;
-		case MSCRATCHI_REGNUM:
-		  reg_name = "mscratchi";
-		  break;
-		case MSCRATCHO_REGNUM:
-		  reg_name = "mscratcho";
+		case MSCRATCHCSW_REGNUM:
+		  reg_name = "mscratchcsw";
 		  break;
 		}
 	      
@@ -3547,7 +3549,7 @@ riscv_compute_frame_info (void)
 
       /* In an SiFive CLIC preemptible interrupt function, we need extra space
 	 for the initial saves of S0 and S1.  */
-      if (cfun->machine->sifive_clic_preemptible_p)
+      if (cfun->machine->interrupt_flags.sifive_clic_preemptible_p)
 	x_save_size = RISCV_STACK_ALIGN ((num_x_saved + 2) * UNITS_PER_WORD);
 
       /* Only use save/restore routines if they don't alter the stack size.  */
@@ -3882,9 +3884,9 @@ riscv_expand_prologue (void)
     }
 
   /* Swap in the stack pointer from the mscratch register.  */
-  if (cfun->machine->sifive_clic_stack_swap_p)
+  if (cfun->machine->interrupt_flags.sifive_clic_stack_swap_p)
     emit_insn (gen_riscv_csr_read_write (stack_pointer_rtx,
-					 GEN_INT (MSCRATCHI_REGNUM),
+					 GEN_INT (MSCRATCHCSW_REGNUM),
 					 stack_pointer_rtx));
 
   /* Save the registers.  */
@@ -3898,7 +3900,7 @@ riscv_expand_prologue (void)
       RTX_FRAME_RELATED_P (emit_insn (insn)) = 1;
       size -= step1;
 
-      if (cfun->machine->sifive_clic_preemptible_p)
+      if (cfun->machine->interrupt_flags.sifive_clic_preemptible_p)
 	{
 	  /* Save S0 and S1.  */
 	  riscv_save_restore_reg (word_mode, S0_REGNUM,
@@ -3932,7 +3934,7 @@ riscv_expand_prologue (void)
   /* Set up the frame pointer, if we're using one.  */
   if (frame_pointer_needed)
     {
-      if (cfun->machine->sifive_clic_preemptible_p)
+      if (cfun->machine->interrupt_flags.sifive_clic_preemptible_p)
 	error ("SiFive CLIC preemptible %qs function cannot use a frame pointer",
 	       "interrupt");
 
@@ -4106,7 +4108,7 @@ riscv_expand_epilogue (int style)
 
   if (use_restore_libcall)
     frame->mask = 0; /* Temporarily fib that we need not save GPRs.  */
-  else if (cfun->machine->sifive_clic_preemptible_p)
+  else if (cfun->machine->interrupt_flags.sifive_clic_preemptible_p)
     interrupt_size = 2 * UNITS_PER_WORD;
 
   /* Restore the registers.  */
@@ -4120,7 +4122,7 @@ riscv_expand_epilogue (int style)
       gcc_assert (step2 >= frame->save_libcall_adjustment);
       step2 -= frame->save_libcall_adjustment;
     }
-  else if (cfun->machine->sifive_clic_preemptible_p
+  else if (cfun->machine->interrupt_flags.sifive_clic_preemptible_p
 	   && (frame->mask | frame->fmask) != 0)
     {
       /* Disable interrupts.  */
@@ -4135,7 +4137,7 @@ riscv_expand_epilogue (int style)
       emit_insn (gen_riscv_csr_write (GEN_INT (MCAUSE_REGNUM),
 				      gen_rtx_REG (word_mode, S0_REGNUM)));
 
-      /* Restore S0 and  S1.  */
+      /* Restore S0 and S1.  */
       riscv_save_restore_reg (word_mode, S1_REGNUM,
 			      step2 - (2 * UNITS_PER_WORD),
 			      riscv_restore_reg);
@@ -4162,10 +4164,10 @@ riscv_expand_epilogue (int style)
       REG_NOTES (insn) = dwarf;
     }
 
-  /* Swap out the stack opinter from the mscratch register.  */
-  if (cfun->machine->sifive_clic_stack_swap_p)
+  /* Swap out the stack pointer from the mscratch register.  */
+  if (cfun->machine->interrupt_flags.sifive_clic_stack_swap_p)
     emit_insn (gen_riscv_csr_read_write (stack_pointer_rtx,
-					 GEN_INT (MSCRATCHO_REGNUM),
+					 GEN_INT (MSCRATCHCSW_REGNUM),
 					 stack_pointer_rtx));
 
   if (use_restore_libcall)
@@ -4187,7 +4189,8 @@ riscv_expand_epilogue (int style)
   /* Return from interrupt.  */
   if (cfun->machine->interrupt_handler_p)
     {
-      enum riscv_privilege_levels mode = cfun->machine->interrupt_mode;
+      enum riscv_privilege_levels mode
+	= cfun->machine->interrupt_flags.interrupt_mode;
 
       gcc_assert (mode != UNKNOWN_MODE);
 
@@ -4853,35 +4856,41 @@ riscv_function_ok_for_sibcall (tree decl ATTRIBUTE_UNUSED,
   return true;
 }
 
-/* Get the interrupt type, return UNKNOWN_MODE if it's not
+/* Get the interrupt type, return UNKNOWN_MODE if it's not an
    interrupt function. */
-/* ??? HACK ??? */
-static void
+static struct riscv_interrupt_flags
 riscv_get_interrupt_type (tree decl)
 {
+  struct riscv_interrupt_flags interrupt_flags;
+  bool interrupt_mode_set;
+ 
   gcc_assert (decl != NULL_TREE);
 
   if ((TREE_CODE(decl) != FUNCTION_DECL)
       || (!riscv_interrupt_type_p (TREE_TYPE (decl))))
-    return UNKNOWN_MODE;
+    {
+      interrupt_flags.interrupt_mode = UNKNOWN_MODE;
+      return interrupt_flags;
+    }
 
   tree attr_args
     = TREE_VALUE (lookup_attribute ("interrupt",
 				    TYPE_ATTRIBUTES (TREE_TYPE (decl))));
 
-  bool interrupt_mode_set = FALSE;
- 
   /* Interrupt attributes are machine mode by default.  */
-  cfun->machine->interrupt_mode = MACHINE_MODE;
+  interrupt_flags.interrupt_mode = MACHINE_MODE;
+  interrupt_flags.sifive_clic_preemptible_p = FALSE;
+  interrupt_flags.sifive_clic_stack_swap_p = FALSE;
+  interrupt_mode_set = FALSE;
 
   while (attr_args)
     {
       const char *string = TREE_STRING_POINTER (TREE_VALUE (attr_args));
 
       if (!strcmp (string, "SiFive-CLIC-preemptible"))
-	cfun->machine->sifive_clic_preemptible_p = TRUE;
+	interrupt_flags.sifive_clic_preemptible_p = TRUE;
       else if (!strcmp (string, "SiFive-CLIC-stack-swap"))
-	cfun->machine->sifive_clic_stack_swap_p = TRUE;
+	interrupt_flags.sifive_clic_stack_swap_p = TRUE;
       else
 	{
 	  if (interrupt_mode_set)
@@ -4889,17 +4898,20 @@ riscv_get_interrupt_type (tree decl)
 	  interrupt_mode_set = TRUE;
 
 	  if (!strcmp (string, "user"))
-	    cfun->machine->interrupt_mode = USER_MODE;
+	    interrupt_flags.interrupt_mode = USER_MODE;
 	  else if (!strcmp (string, "supervisor"))
-	    cfun->machine->interrupt_mode = SUPERVISOR_MODE;
+	    interrupt_flags.interrupt_mode = SUPERVISOR_MODE;
 	  else if (!strcmp (string, "machine"))
-	    cfun->machine->interrupt_mode = MACHINE_MODE;
+	    interrupt_flags.interrupt_mode = MACHINE_MODE;
 	  else
+	    /* Unreachable.  Checked in riscv_handle_type_attribute.  */
 	    abort ();
 	}
 
       attr_args = TREE_CHAIN (attr_args);
     }
+
+  return interrupt_flags;
 }
 
 /* Implement `TARGET_SET_CURRENT_FUNCTION'.  */
@@ -4933,43 +4945,43 @@ riscv_set_current_function (tree decl)
       if (args && TREE_CODE (TREE_VALUE (args)) != VOID_TYPE)
 	error ("%qs function cannot have arguments", "interrupt");
 
-      riscv_get_interrupt_type (decl);
+      cfun->machine->interrupt_flags = riscv_get_interrupt_type (decl);
 
-      if (cfun->machine->interrupt_mode != MACHINE_MODE)
+      if (cfun->machine->interrupt_flags.interrupt_mode != MACHINE_MODE)
 	{
-	  if (cfun->machine->sifive_clic_preemptible_p)
+	  if (cfun->machine->interrupt_flags.sifive_clic_preemptible_p)
 	    error ("SiFive CLIC preemptible %qs function must be machine mode",
 		   "interrupt");
-	  else if (cfun->machine->sifive_clic_stack_swap_p)
+	  else if (cfun->machine->interrupt_flags.sifive_clic_stack_swap_p)
 	    error ("SiFive CLIC stack-swap %qs function must be machine mode",
 		   "interrupt");
 	}
 
-      gcc_assert (cfun->machine->interrupt_mode != UNKNOWN_MODE);
+      gcc_assert (cfun->machine->interrupt_flags.interrupt_mode
+		  != UNKNOWN_MODE);
     }
 
   /* Don't print the above diagnostics more than once.  */
   cfun->machine->attributes_checked_p = 1;
 }
 
-#if 0
-/* ??? HACK ??? */
-/* Implement TARGET_MERGE_DECL_ATTRIBUTES. */
+/* Implement TARGET_MERGE_DECL_ATTRIBUTES.  */
 static tree
 riscv_merge_decl_attributes (tree olddecl, tree newdecl)
 {
   tree combined_attrs;
 
-  enum riscv_privilege_levels old_interrupt_type
+  struct riscv_interrupt_flags old_interrupt_type
     = riscv_get_interrupt_type (olddecl);
-  enum riscv_privilege_levels new_interrupt_type
+  struct riscv_interrupt_flags new_interrupt_type
     = riscv_get_interrupt_type (newdecl);
 
-  /* Check old and new has same interrupt type. */
-  if ((old_interrupt_type != UNKNOWN_MODE)
-      && (new_interrupt_type != UNKNOWN_MODE)
-      && (old_interrupt_type != new_interrupt_type))
-    error ("%qs function cannot have different interrupt type", "interrupt");
+  /* Check old and new have same interrupt type.  */
+  if ((old_interrupt_type.interrupt_mode != UNKNOWN_MODE)
+      && (new_interrupt_type.interrupt_mode != UNKNOWN_MODE)
+      && (old_interrupt_type.interrupt_mode
+	  != new_interrupt_type.interrupt_mode))
+    error ("%qs function cannot have different interrupt type.", "interrupt");
 
   /* Create combined attributes.  */
   combined_attrs = merge_attributes (DECL_ATTRIBUTES (olddecl),
@@ -4977,7 +4989,6 @@ riscv_merge_decl_attributes (tree olddecl, tree newdecl)
 
   return combined_attrs;
 }
-#endif
 
 /* Implement TARGET_CANNOT_COPY_INSN_P.  */
 
@@ -5175,11 +5186,8 @@ riscv_constant_alignment (const_tree exp, HOST_WIDE_INT align)
 #undef TARGET_CONSTANT_ALIGNMENT
 #define TARGET_CONSTANT_ALIGNMENT riscv_constant_alignment
 
-#if 0
-/* ??? HACK ??? */
 #undef TARGET_MERGE_DECL_ATTRIBUTES
 #define TARGET_MERGE_DECL_ATTRIBUTES riscv_merge_decl_attributes
-#endif
 
 #undef TARGET_ATTRIBUTE_TABLE
 #define TARGET_ATTRIBUTE_TABLE riscv_attribute_table
diff --git a/gcc/config/riscv/riscv.md b/gcc/config/riscv/riscv.md
index 3b7d4f92c1c..a27e921d5a9 100644
--- a/gcc/config/riscv/riscv.md
+++ b/gcc/config/riscv/riscv.md
@@ -94,8 +94,7 @@
    (MSTATUS_REGNUM		0x300)
    (MEPC_REGNUM			0x341)
    (MCAUSE_REGNUM		0x342)
-   (MSCRATCHI_REGNUM		0x348)
-   (MSCRATCHO_REGNUM		0x349)
+   (MSCRATCHCSW_REGNUM		0x348)
 
    (MSTATUS_MIE_BIT		8)
 ])
diff --git a/gcc/testsuite/gcc.target/riscv/interrupt-conflict-mode.c b/gcc/testsuite/gcc.target/riscv/interrupt-conflict-mode.c
index e9f145265c0..793397feaf4 100644
--- a/gcc/testsuite/gcc.target/riscv/interrupt-conflict-mode.c
+++ b/gcc/testsuite/gcc.target/riscv/interrupt-conflict-mode.c
@@ -6,5 +6,5 @@ foo(void);
 
 void __attribute__ ((interrupt ("machine")))
 foo (void)
-{ /* { dg-error "function cannot have different interrupt type" } */
+{ /* { dg-error "function cannot have different interrupt type." } */
 }
diff --git a/gcc/testsuite/gcc.target/riscv/stack-swap-1.c b/gcc/testsuite/gcc.target/riscv/stack-swap-1.c
index 2e26432cd89..bbc89b58e18 100644
--- a/gcc/testsuite/gcc.target/riscv/stack-swap-1.c
+++ b/gcc/testsuite/gcc.target/riscv/stack-swap-1.c
@@ -14,5 +14,4 @@ foo2 (void)
   COUNTER++;
 #endif
 }
-/* { dg-final { scan-assembler "mscratchi" } } */
-/* { dg-final { scan-assembler "mscratcho" } } */
+/* { dg-final { scan-assembler-times "mscratchcsw" 2 } } */
-- 
2.21.0