RISC-V: Bugfix function target attribute pollution

This patch depends on below ICE fix.

https://gcc.gnu.org/pipermail/gcc-patches/2024-March/647915.html

The function target attribute should be on a per-function basis.
For example, we have 3 function as below:

void test_1 () {}

void __attribute__((target("arch=+v"))) test_2 () {}

void __attribute__((target("arch=+zfh"))) test_3 () {}

void test_4 () {}

The scope of the target attribute should not extend the function body.
Aka, test_3 cannot have the 'v' extension, as well as the test_4
cannot have both the 'v' and 'zfh' extension.

Unfortunately, for now the test_4 is able to leverage the 'v' and
the 'zfh' extension which is incorrect.  This patch would like to
fix the sticking attribute by introduce the commandline subset_list.
When parse_arch, we always clone from the cmdline_subset_list instead
of the current_subset_list.

Meanwhile, we correct the print information about arch like below.

.option arch, rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zicsr2p0_zifencei2p0_zbb1p0

The riscv_declare_function_name hook is always after the hook
riscv_process_target_attr.  Thus, we introduce one hash_map to record
the 1:1 mapping from fndel to its' subset_list in advance.  And later
the riscv_declare_function_name is able to get the right information
about the arch.

Below test are passed for this patch
* The riscv fully regression test.

	PR target/114352

gcc/ChangeLog:

	* common/config/riscv/riscv-common.cc (struct riscv_func_target_info):
	New struct for func decl and target name.
	(struct riscv_func_target_hasher): New hasher for hash table mapping
	from the fn_decl to fn_target_name.
	(riscv_func_decl_hash): New func to compute the hash for fn_decl.
	(riscv_func_target_hasher::hash): New func to impl hash interface.
	(riscv_func_target_hasher::equal): New func to impl equal interface.
	(riscv_cmdline_subset_list): New static var for cmdline subset list.
	(riscv_func_target_table_lazy_init): New func to lazy init the func
	target hash table.
	(riscv_func_target_get): New func to get target name from hash table.
	(riscv_func_target_put): New func to put target name into hash table.
	(riscv_func_target_remove_and_destory): New func to remove target
	info from the hash table and destory it.
	(riscv_parse_arch_string): Set the static var cmdline_subset_list.
	* config/riscv/riscv-subset.h (riscv_cmdline_subset_list): New static
	var for cmdline subset list.
	(riscv_func_target_get): New func decl.
	(riscv_func_target_put): Ditto.
	(riscv_func_target_remove_and_destory): Ditto.
	* config/riscv/riscv-target-attr.cc (riscv_target_attr_parser::parse_arch):
	Take cmdline_subset_list instead of current_subset_list when clone.
	(riscv_process_target_attr): Record the func target info to hash table.
	(riscv_option_valid_attribute_p): Add new arg tree fndel.
	* config/riscv/riscv.cc (riscv_declare_function_name): Consume the
	func target info and print the arch message.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/base/pr114352-3.c: New test.

Signed-off-by: Pan Li <pan2.li@intel.com>

gcc/common/config/riscv/riscv-common.cc

@@ -426,11 +426,108 @@ bool riscv_subset_list::parse_failed = false;
 
 static riscv_subset_list *current_subset_list = NULL;
 
+static riscv_subset_list *cmdline_subset_list = NULL;
+
+struct riscv_func_target_info
+{
+  tree fn_decl;
+  std::string fn_target_name;
+
+  riscv_func_target_info (const tree &decl, const std::string &target_name)
+    : fn_decl (decl), fn_target_name (target_name)
+  {
+  }
+};
+
+struct riscv_func_target_hasher : nofree_ptr_hash<struct riscv_func_target_info>
+{
+  typedef tree compare_type;
+
+  static hashval_t hash (value_type);
+  static bool equal (value_type, const compare_type &);
+};
+
+static hash_table<riscv_func_target_hasher> *func_target_table = NULL;
+
+static inline hashval_t riscv_func_decl_hash (tree fn_decl)
+{
+  inchash::hash h;
+
+  h.add_ptr (fn_decl);
+
+  return h.end ();
+}
+
+inline hashval_t
+riscv_func_target_hasher::hash (value_type value)
+{
+  return riscv_func_decl_hash (value->fn_decl);
+}
+
+inline bool
+riscv_func_target_hasher::equal (value_type value, const compare_type &key)
+{
+  return value->fn_decl == key;
+}
+
 const riscv_subset_list *riscv_current_subset_list ()
 {
   return current_subset_list;
 }
 
+const riscv_subset_list * riscv_cmdline_subset_list ()
+{
+  return cmdline_subset_list;
+}
+
+static inline void riscv_func_target_table_lazy_init ()
+{
+  if (func_target_table != NULL)
+    return;
+
+  func_target_table = new hash_table<riscv_func_target_hasher> (1023);
+}
+
+std::string * riscv_func_target_get (tree fn_decl)
+{
+  riscv_func_target_table_lazy_init ();
+
+  hashval_t hash = riscv_func_decl_hash (fn_decl);
+  struct riscv_func_target_info *info
+    = func_target_table->find_with_hash (fn_decl, hash);
+
+  return info == NULL ? NULL : &info->fn_target_name;
+}
+
+void riscv_func_target_put (tree fn_decl, std::string fn_target_name)
+{
+  riscv_func_target_table_lazy_init ();
+
+  hashval_t hash = riscv_func_decl_hash (fn_decl);
+  struct riscv_func_target_info **target_info_slot
+    = func_target_table->find_slot_with_hash (fn_decl, hash, INSERT);
+
+  gcc_assert (!*target_info_slot);
+
+  struct riscv_func_target_info *info
+    = new riscv_func_target_info (fn_decl, fn_target_name);
+
+  *target_info_slot = info;
+}
+
+void riscv_func_target_remove_and_destory (tree fn_decl)
+{
+  hashval_t hash = riscv_func_decl_hash (fn_decl);
+  struct riscv_func_target_info *info
+    = func_target_table->find_with_hash (fn_decl, hash);
+
+  if (info)
+    {
+      func_target_table->remove_elt_with_hash (fn_decl, hash);
+      delete info;
+    }
+}
+
 /* struct for recording multi-lib info.  */
 struct riscv_multi_lib_info_t {
   std::string path;
@@ -1731,10 +1828,14 @@ riscv_parse_arch_string (const char *isa,
 	}
     }
 
-  if (current_subset_list)
+  /* Avoid double delete if current_subset_list equals cmdline_subset_list.  */
+  if (current_subset_list && current_subset_list != cmdline_subset_list)
     delete current_subset_list;
 
-  current_subset_list = subset_list;
+  if (cmdline_subset_list)
+    delete cmdline_subset_list;
+
+  current_subset_list = cmdline_subset_list = subset_list;
 }
 
 /* Return the riscv_cpu_info entry for CPU, NULL if not found.  */

gcc/config/riscv/riscv-subset.h

@@ -110,6 +110,10 @@ public:
 };
 
 extern const riscv_subset_list *riscv_current_subset_list (void);
+extern const riscv_subset_list *riscv_cmdline_subset_list (void);
+extern std::string * riscv_func_target_get (tree);
+extern void riscv_func_target_put (tree, std::string);
+extern void riscv_func_target_remove_and_destory (tree);
 extern void
 riscv_set_arch_by_subset_list (riscv_subset_list *, struct gcc_options *);
 

gcc/config/riscv/riscv-target-attr.cc

@@ -54,6 +54,10 @@ public:
     m_loc = loc;
   }
 
+  riscv_subset_list* get_riscv_subset_list () {
+    return m_subset_list;
+  }
+
   void update_settings (struct gcc_options *opts) const;
 private:
   const char *m_raw_attr_str;
@@ -109,7 +113,7 @@ riscv_target_attr_parser::parse_arch (const char *str)
       char *str_to_check = buf.get ();
       strcpy (str_to_check, str);
       const char *token = strtok_r (str_to_check, ",", &str_to_check);
-      m_subset_list = riscv_current_subset_list ()->clone ();
+      m_subset_list = riscv_cmdline_subset_list ()->clone ();
       m_subset_list->set_loc (m_loc);
       while (token)
 	{
@@ -297,7 +301,8 @@ num_occurences_in_str (char c, char *str)
    and update the global target options space.  */
 
 static bool
-riscv_process_target_attr (tree args, location_t loc, struct gcc_options *opts)
+riscv_process_target_attr (tree fndecl, tree args, location_t loc,
+			   struct gcc_options *opts)
 {
   if (TREE_CODE (args) == TREE_LIST)
     {
@@ -306,7 +311,7 @@ riscv_process_target_attr (tree args, location_t loc, struct gcc_options *opts)
 	  tree head = TREE_VALUE (args);
 	  if (head)
 	    {
-	      if (!riscv_process_target_attr (head, loc, opts))
+	      if (!riscv_process_target_attr (fndecl, head, loc, opts))
 		return false;
 	    }
 	  args = TREE_CHAIN (args);
@@ -359,6 +364,11 @@ riscv_process_target_attr (tree args, location_t loc, struct gcc_options *opts)
   /* Apply settings from target attribute.  */
   attr_parser.update_settings (opts);
 
+  /* Add the string of the target attribute to the fndecl hash table.  */
+  riscv_subset_list *subset_list = attr_parser.get_riscv_subset_list ();
+  if (subset_list)
+    riscv_func_target_put (fndecl, subset_list->to_string (true));
+
   return true;
 }
 
@@ -376,7 +386,7 @@ riscv_option_valid_attribute_p (tree fndecl, tree, tree args, int)
   /* Save the current target options to restore at the end.  */
   cl_target_option_save (&cur_target, &global_options, &global_options_set);
 
-  ret = riscv_process_target_attr (args, loc, &global_options);
+  ret = riscv_process_target_attr (fndecl, args, loc, &global_options);
 
   if (ret)
     {

gcc/config/riscv/riscv.cc

@@ -8691,8 +8691,13 @@ riscv_declare_function_name (FILE *stream, const char *name, tree fndecl)
   if (DECL_FUNCTION_SPECIFIC_TARGET (fndecl))
     {
       fprintf (stream, "\t.option push\n");
-      std::string isa = riscv_current_subset_list ()->to_string (true);
+
+      std::string *target_name = riscv_func_target_get (fndecl);
+      std::string isa = target_name != NULL
+	? *target_name
+	: riscv_cmdline_subset_list ()->to_string (true);
       fprintf (stream, "\t.option arch, %s\n", isa.c_str ());
+      riscv_func_target_remove_and_destory (fndecl);
 
       struct cl_target_option *local_cl_target =
 	TREE_TARGET_OPTION (DECL_FUNCTION_SPECIFIC_TARGET (fndecl));

gcc/testsuite/gcc.target/riscv/rvv/base/pr114352-3.c

@@ -0,0 +1,113 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc -mabi=lp64 -O3 -fno-schedule-insns -fno-schedule-insns2" } */
+/* { dg-final { check-function-bodies "**" "" } } */
+
+/*
+** test_1:
+** sext\.w\s+[atx][0-9]+,\s*[atx][0-9]+
+** ...
+*/
+void
+test_1 (int *a, int *b, int *out, unsigned count)
+{
+  unsigned i;
+
+  count = count > 128 ? 128 : count;
+
+  for (i = 0; i < count; i++)
+    out[i] = a[i] + b[i];
+}
+
+/*
+** test_2:
+** ...
+** vadd\.vv\s+v[0-9]+,\s*v[0-9]+,\s*v[0-9]+
+** ...
+*/
+void
+__attribute__((target("arch=+v")))
+test_2 (int *a, int *b, int *out, unsigned count)
+{
+  unsigned i;
+
+  count = count > 128 ? 128 : count;
+
+  for (i = 0; i < count; i++)
+    out[i] = a[i] + b[i];
+}
+
+/*
+** test_3:
+** ...
+** minu\s+[atx][0-9]+,\s*[atx][0-9]+,\s*[atx][0-9]+
+** ...
+*/
+void
+__attribute__((target("arch=+zbb")))
+test_3 (int *a, int *b, int *out, unsigned count)
+{
+  unsigned i;
+
+  count = count > 128 ? 128 : count;
+
+  for (i = 0; i < count; i++)
+    out[i] = a[i] + b[i];
+}
+
+/*
+** test_4:
+** sext\.w\s+[atx][0-9]+,\s*[atx][0-9]+
+** ...
+*/
+void
+test_4 (int *a, int *b, int *out, unsigned count)
+{
+  unsigned i;
+
+  count = count > 128 ? 128 : count;
+
+  for (i = 0; i < count; i++)
+    out[i] = a[i] + b[i];
+}
+
+/*
+** test_5:
+** ...
+** fadd\.h\s+fa[0-9]+,\s*fa[0-9]+,\s*fa[0-9]+
+** ...
+*/
+void
+__attribute__((target("arch=+zfh")))
+test_5 (_Float16 *a, _Float16 *b, _Float16 *out, unsigned count)
+{
+  unsigned i;
+
+  count = count > 128 ? 128 : count;
+
+  for (i = 0; i < count; i++)
+    out[i] = a[i] + b[i];
+}
+
+/*
+** test_6:
+** ...
+** call\s+__extendhfsf2
+** ...
+** call\s+__truncsfhf2
+** ...
+*/
+void
+test_6 (_Float16 *a, _Float16 *b, _Float16 *out, unsigned count)
+{
+  unsigned i;
+
+  count = count > 128 ? 128 : count;
+
+  for (i = 0; i < count; i++)
+    out[i] = a[i] + b[i];
+}
+
+/* { dg-final { scan-assembler ".attribute arch, \"rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zicsr2p0_zifencei2p0\"" } } */
+/* { dg-final { scan-assembler ".option arch, rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_v1p0_zicsr2p0_zifencei2p0_zve32f1p0_zve32x1p0_zve64d1p0_zve64f1p0_zve64x1p0_zvl128b1p0_zvl32b1p0_zvl64b1p0" } } */
+/* { dg-final { scan-assembler ".option arch, rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zicsr2p0_zifencei2p0_zbb1p0" } } */
+/* { dg-final { scan-assembler ".option arch, rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_zicsr2p0_zifencei2p0_zfh1p0_zfhmin1p0" } } */