Merge #1471

1471: Remove target hooks changes r=philberty a=philberty

This reverts the unnecessary changes we have made to GCC
so that merging from upstream should be simplified. This is
also making writing the patches for GCC simpler.

Co-authored-by: Philip Herron <philip.herron@embecosm.com>
Co-authored-by: Thomas Schwinge <thomas@codesourcery.com>

6 files changed, 3 insertions, 401 deletions

diff --git a/gcc/rust/rust-lang.cc b/gcc/rust/rust-lang.cc
index ed822cc..c9af790 100644
--- a/gcc/rust/rust-lang.cc
+++ b/gcc/rust/rust-lang.cc
@@ -104,6 +104,8 @@ struct GTY (()) language_function
 void
 rust_add_target_info (const char *key, const char *value)
 {
+  sorry ("TODO");
+
   Rust::Session::get_instance ().options.target_data.insert_key_value_pair (
     key, value);
 }
diff --git a/gcc/rust/rust-session-manager.cc b/gcc/rust/rust-session-manager.cc
index 7d599b1..6d7f1a8 100644
--- a/gcc/rust/rust-session-manager.cc
+++ b/gcc/rust/rust-session-manager.cc
@@ -41,8 +41,8 @@
 
 #include "diagnostic.h"
 #include "input.h"
-#include "rust-target.h"
 #include "selftest.h"
+#include "target.h"
 
 extern bool
 saw_errors (void);
@@ -131,256 +131,15 @@ validate_crate_name (const std::string &crate_name, Error &error)
   return true;
 }
 
-// Implicitly enable a target_feature (and recursively enable dependencies).
-void
-Session::implicitly_enable_feature (std::string feature_name)
-{
-  // TODO: is this really required since features added would be complete via
-  // target spec?
-
-  if (!options.target_data.has_key_value_pair ("target_feature", feature_name))
-    {
-      // if feature has dependencies, enable them
-      if (feature_name == "aes")
-	{
-	  implicitly_enable_feature ("sse2");
-	}
-      else if (feature_name == "avx")
-	{
-	  implicitly_enable_feature ("sse4.2");
-	}
-      else if (feature_name == "avx2")
-	{
-	  implicitly_enable_feature ("avx");
-	}
-      else if (feature_name == "fma")
-	{
-	  implicitly_enable_feature ("avx");
-	}
-      else if (feature_name == "pclmulqdq")
-	{
-	  implicitly_enable_feature ("sse2");
-	}
-      else if (feature_name == "sha")
-	{
-	  implicitly_enable_feature ("sse2");
-	}
-      else if (feature_name == "sse2")
-	{
-	  implicitly_enable_feature ("sse");
-	}
-      else if (feature_name == "sse3")
-	{
-	  implicitly_enable_feature ("sse2");
-	}
-      else if (feature_name == "sse4.1")
-	{
-	  implicitly_enable_feature ("sse3");
-	}
-      else if (feature_name == "sse4.2")
-	{
-	  implicitly_enable_feature ("sse4.1");
-	}
-      else if (feature_name == "ssse3")
-	{
-	  implicitly_enable_feature ("sse3");
-	}
-
-      options.target_data.insert_key_value_pair ("target_feature",
-						 std::move (feature_name));
-    }
-}
-
-// Meant to enable all target features. As this will be done by target hook,
-// this method's deprecated.
-void
-Session::enable_features ()
-{
-  bool has_target_crt_static = false;
-
-  rust_debug (
-    "ERROR: Somewhere in call chain Session::enable_features is called.");
-
-  if (has_target_crt_static)
-    {
-      // enable "crt-static" attribute
-    }
-
-  /* TODO: do this via target hook. have one for each target that implicitly
-   * enables the
-   * features for that platform. Would probably have to make custom target hook.
-   */
-
-  /*
-  if (target == "x86" || target == "x86_64") {
-      if (TARGET_AES) {
-	  // enable aes, implicitly enable sse2
-	  implicitly_enable_feature("aes");
-      }
-
-      if (TARGET_AVX) {
-	  // enable avx, implicitly enable sse4.2
-	  implicitly_enable_feature("sse4.2");
-      }
-
-      if (TARGET_AVX2) {
-	  // enable avx2, implicitly enable avx
-	  implicitly_enable_feature("avx");
-      }
-
-      if (TARGET_BMI) {
-	  // enable bmi1
-	  implicitly_enable_feature("bmi1");
-      }
-
-      if (TARGET_BMI2) {
-	  // enable bmi2
-	  implicitly_enable_feature("bmi2");
-      }
-
-      if (TARGET_FMA) {
-	  // enable fma, implicitly enable avx
-	  implicitly_enable_feature("fma");
-      }
-
-      if (TARGET_FXSR) {
-	  // enable fxsr
-	  implicitly_enable_feature("fxsr");
-      }
-
-      if (TARGET_LZCNT) {
-	  // enable lzcnt
-	  implicitly_enable_feature("lzcnt");
-      }
-
-      if (TARGET_VPCLMULQDQ) {
-	  // enable pclmulqdq, implicitly enable sse2
-	  implicitly_enable_feature("pclmulqdq");
-      }
-
-      if (TARGET_POPCNT) {
-	  // enable popcnt
-	  implicitly_enable_feature("popcnt");
-      }
-
-      if (TARGET_RDRND) {
-	  // enable rdrand
-	  implicitly_enable_feature("rdrand");
-      }
-
-      if (TARGET_RDSEED) {
-	  // enable rdseed
-	  implicitly_enable_feature("rdseed");
-      }
-
-      if (TARGET_SHA) {
-	  // enable sha, implicitly enable sse2
-	  implicitly_enable_feature("sha");
-      }
-
-      if (TARGET_SSE) {
-	  // enable sse
-	  implicitly_enable_feature("sse");
-      }
-
-      if (TARGET_SSE2) {
-	  // enable sse2, implicitly enable sse
-	  implicitly_enable_feature("sse2");
-      }
-
-      if (TARGET_SSE3) {
-	  // enable sse3, implicitly enable sse2
-	  implicitly_enable_feature("sse3");
-      }
-
-      if (TARGET_SSE4_1) {
-	  // enable sse4.1, implicitly enable sse3
-	  implicitly_enable_feature("sse4.1");
-      }
-
-      if (TARGET_SSE4_2) {
-	  // enable sse4.2, implicitly enable sse4.1
-	  implicitly_enable_feature("sse4.2");
-      }
-
-      if (TARGET_SSSE3) {
-	  // enable ssse3, implicitly enable sse3
-	  implicitly_enable_feature("ssse3");
-      }
-
-      if (TARGET_XSAVE) {
-	  // enable xsave
-	  implicitly_enable_feature("xsave");
-      }
-
-      if (TARGET_XSAVEC) {
-	  // enable xsavec
-	  implicitly_enable_feature("xsavec");
-      }
-
-      if (TARGET_XSAVEOPT) {
-	  // enable xsaveopt
-	  implicitly_enable_feature("xsaveopt");
-      }
-
-      if (TARGET_XSAVES) {
-	  // enable xsaves
-	  implicitly_enable_feature("xsaves");
-      }
-  }
-  options.target_data.features.shrink_to_fit();
-  std::sort(options.target_data.features.begin(),
-  options.target_data.features.end());*/
-}
-
 void
 Session::init ()
 {
-#ifndef TARGET_RUST_OS_INFO
-#define TARGET_RUST_OS_INFO()
-#endif
-//#define builtin_rust_info(KEY, VALUE) rust_add_target_info (KEY, VALUE)
-// might as well use c++ stuff
-#define builtin_rust_info(KEY, VALUE)                                          \
-  options.target_data.insert_key_value_pair (KEY, VALUE)
-
-  // initialise target hooks
-  // targetrustm.rust_cpu_info();
-  // targetrustm.rust_os_info();
-  // ok, that's not working too well TODO - see if can salvage old
-  // implementation
-  TARGET_RUST_CPU_INFO ();
-  TARGET_RUST_OS_INFO ();
-
-  /* note that due to issues with gcc targets, some implementations of those two
-   * macros above (TARGET_RUST_CPU_INFO and TARGET_RUST_OS_INFO) are not
-   * function calls, but actually inline substitutions. As such, they can't be
-   * stored with a function pointer in a "real" target hook.
-   * At least, that's my current understanding of it. */
-
-#undef builtin_rust_info
-
-  // target-independent values that should exist in all targets
   options.target_data.insert_key_value_pair ("target_pointer_width",
 					     std::to_string (POINTER_SIZE));
   options.target_data.insert_key_value_pair ("target_endian", BYTES_BIG_ENDIAN
 								? "big"
 								: "little");
 
-  // TODO: find min atomic width and max atomic width
-  // from it, add atomic-related stuff for sizes 8, 16, 32, 64, and 128 (if
-  // inside bounds) in rustc, min atomic width is a known quantity (or 8 if not
-  // known), and max is also a known quantity (or is pointer size if not known)
-  // TODO: add atomic pointer if some criteria is satisfied
-
-  // TODO: find whether target has "atomic cas"
-
-  // add debug_assertions if enabled and proc_macro if crate type has it or
-  // whatever
-
-  // derived values from hook
-  options.target_data.init_derived_values ();
-
   // setup singleton linemap
   linemap = rust_get_linemap ();
 
diff --git a/gcc/rust/rust-session-manager.h b/gcc/rust/rust-session-manager.h
index 2432de7..99dd107 100644
--- a/gcc/rust/rust-session-manager.h
+++ b/gcc/rust/rust-session-manager.h
@@ -325,9 +325,6 @@ private:
   void dump_hir_pretty (HIR::Crate &crate) const;
   void dump_type_resolution (HIR::Crate &crate) const;
 
-  void implicitly_enable_feature (std::string feature_name);
-  void enable_features ();
-
   // pipeline stages - TODO maybe move?
   /* Register plugins pipeline stage. TODO maybe move to another object?
    * Currently dummy stage. In future will handle attribute injection
diff --git a/gcc/rust/rust-target-def.h b/gcc/rust/rust-target-def.h
deleted file mode 100644
index 94c3f9f..0000000
--- a/gcc/rust/rust-target-def.h
+++ /dev/null
@@ -1,20 +0,0 @@
-/* rust-target-def.h -- Default initializers for Rust target hooks.
-   Copyright (C) 2020-2022 Free Software Foundation, Inc.
-
-   This program is free software; you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published by the
-   Free Software Foundation; either version 3, or (at your option) any
-   later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; see the file COPYING3.  If not see
-   <http://www.gnu.org/licenses/>.  */
-
-#include "rust/rust-target-hooks-def.h"
-#include "tree.h"
-#include "hooks.h"
diff --git a/gcc/rust/rust-target.def b/gcc/rust/rust-target.def
deleted file mode 100644
index 6d1ccaf..0000000
--- a/gcc/rust/rust-target.def
+++ /dev/null
@@ -1,89 +0,0 @@
-/* rust-target.def -- Target hook definitions for the Rust front end.
-   Copyright (C) 2020-2022 Free Software Foundation, Inc.
-
-   This program is free software; you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published by the
-   Free Software Foundation; either version 3, or (at your option) any
-   later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; see the file COPYING3.  If not see
-   <http://www.gnu.org/licenses/>.  */
-
-/* See target-hooks-macros.h for details of macros that should be
-   provided by the including file, and how to use them here.  */
-
-#include "target-hooks-macros.h"
-
-#undef HOOK_TYPE
-#define HOOK_TYPE "Rust Target Hook"
-
-HOOK_VECTOR (TARGETRUSTM_INITIALIZER, gcc_targetrustm)
-
-#undef HOOK_PREFIX
-#define HOOK_PREFIX "TARGET_"
-
-/* Environmental CPU info and features (e.g. endianness, pointer size) relating to the target CPU.  */
-DEFHOOK
-(rust_cpu_info,
- "Declare all environmental CPU info and features relating to the target CPU\n\
-using the function @code{rust_add_target_info}, which takes a string representing\n\
-the feature key and a string representing the feature value.  Configuration pairs\n\
-predefined by this hook apply to all files that are being compiled.",
- void, (void),
- hook_void_void)
-
-// TODO: remove: format of DEFHOOK is return type, (param types), default value for function that it translates to
-
-/* Environmental OS info relating to the target OS.  */
-DEFHOOK
-(/*d_os_versions*/rust_os_info,
- "Similar to @code{TARGET_RUST_CPU_INFO}, but is used for configuration info\n\
-relating to the target operating system.",
- void, (void),
- hook_void_void)
-
-/* The sizeof CRITICAL_SECTION or pthread_mutex_t.  */
-/*DEFHOOK
-(d_critsec_size,
- "Returns the size of the data structure used by the target operating system\n\
-for critical sections and monitors.  For example, on Microsoft Windows this\n\
-would return the @code{sizeof(CRITICAL_SECTION)}, while other platforms that\n\
-implement pthreads would return @code{sizeof(pthread_mutex_t)}.",
- unsigned, (void),
- hook_uint_void_0)*/
-
- /* TODO: add more if required. Possible ones include static C runtime, target_env
-  * or vendor (if not covered by OS), and flags from the driver that may or may not
-  * require a target hook (might instead require a different type of hook) like 
-  * test, debug_assertions, and proc_macro. */
-
- /* TODO: rustc target support by tier:
-  *   Tier 1 (definitely work):
-  *   -  i686-pc-windows-gnu
-  *   -  i686-pc-windows-msvc
-  *   -  i686-unknown-linux-gnu
-  *   -  x86_64-apple-darwin
-  *   -  x86_64-pc-windows-gnu
-  *   -  x86_64-pc-windows-msvc
-  *   -  x86_64-unknown-linux-gnu
-  *   - Basically, 32-bit and 64-bit x86 for windows (MinGW and MSVC), gnu/linux, and osx
-  *   Other tiers have too much crap, but basic breakdown is:
-  *   Tier 2:
-  *   -  archs: ARM64 (aarch64), ARMv7, ARMv6, asm.js, i586 (32-bit x86 without SSE), mips, 
-  *      mips64, powerpc, powerpc64, risc-v, s390x, sparc, webasm, netbsd, redox (does gcc have support?),
-  *      cloudabi (never head of it; i imagine no gcc support)
-  *   -  oses: ios, fuchsia, android, windows (msvc and mingw), gnu/linux, freebsd, netbsd
-  *   Tier 2.5:
-  *   - powerpc SPE linux, various cloudabi stuff, sparc
-  *   Tier 3:
-  *   - more obscure stuff like UWP support, vxworks, openbsd, dragonflybsd, haiku, bitrig, windows xp,
-  *     cuda, hexagon, and combinations of them and earlier stuff */
-
-/* Close the 'struct gcc_targetrustm' definition.  */
-HOOK_VECTOR_END (C90_EMPTY_HACK)
diff --git a/gcc/rust/rust-target.h b/gcc/rust/rust-target.h
deleted file mode 100644
index 743ac51..0000000
--- a/gcc/rust/rust-target.h
+++ /dev/null
@@ -1,47 +0,0 @@
-/* rust-target.h -- Data structure definitions for target-specific Rust
-   behavior. Copyright (C) 2020-2022 Free Software Foundation, Inc.
-
-   This program is free software; you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published by the
-   Free Software Foundation; either version 3, or (at your option) any
-   later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; see the file COPYING3.  If not see
-   <http://www.gnu.org/licenses/>.  */
-
-#ifndef GCC_RUST_TARGET_H
-#define GCC_RUST_TARGET_H
-
-#include "target.h"
-#include "tm.h"
-#include "memmodel.h"
-#include "tm_p.h"
-
-// TODO: find out what this stuff actually does
-#define DEFHOOKPOD(NAME, DOC, TYPE, INIT) TYPE NAME;
-// #define DEFHOOK(NAME, DOC, TYPE, PARAMS, INIT) TYPE (*NAME) PARAMS;
-#define DEFHOOK_UNDOC DEFHOOK
-#define HOOKSTRUCT(FRAGMENT) FRAGMENT
-
-#include "rust-target.def"
-
-/* Each target can provide their own.  */
-extern struct gcc_targetrustm targetrustm;
-/* Some kind of structure to store all rust hook macros (like the
- * TARGET_RUST_CPU_INFO). This is required to store the function pointers for
- * the target hooks so that the frontend can call them
- * and it calls the correct target-specific function.  */
-
-/* Used by target to add predefined version idenditiers.  */
-// extern void d_add_builtin_version (const char *);
-/* Used by target to add target-related info.  */
-extern void
-rust_add_target_info (const char *key, const char *value);
-
-#endif