Merge pull request #20396 from mppf/chpl-llvm-support-var

Add CHPL_LLVM_SUPPORT and adjust quickstart

Follow-up to PR #19565.

This PR takes two steps to improve the situation after PR #19565.

First, it adds `CHPL_LLVM_SUPPORT` as a `printchplenv` variable. This
variable indicates where to get the LLVM Support Library (which is
currently required to build the compiler). It can be `bundled` or
`system`. See issue #20380.

On the name of this variable, I wondered if `CHPL_LLVM_SUPPORT_LIBRARY`
would be a better name? `CHPL_LLVM_SUPPORT` could be interpreted as "does
Chapel build with LLVM support" but that is what `CHPL_LLVM` does. On the
other hand, since it appears in `printchplenv --all` within the
`CHPL_LLVM` block, I think `CHPL_LLVM_SUPPORT` is OK.

Second, it adjusts the quickstart scripts to set `CHPL_LLVM=system` if a
compatible system LLVM is detected. See issue #20273.

Reviewed by @daviditen - thanks!

- [x] full local testing
- [x] make check with CHPL_LLVM unset where no system LLVM exists produces "Please set the environment variable CHPL_LLVM to a supported value." error
- [x] make check with CHPL_LLVM=none where no system LLVM exists
- [x] make check with CHPL_LLVM=none where a system LLVM exists
- [x] make check with CHPL_LLVM=bundled
- [x] make check with  CHPL_LLVM=system

test/setchplenv/verify_setchplenv_scripts.py

@@ -151,11 +151,12 @@ def get_path_var(var_name):
         self.assertEqual(os.stat(self.chpl_home), os.stat(actual_chpl_home))
 
         if 'quickstart' in os.path.relpath(setchplenv_script, self.util_dir):
+            got_llvm = get_var('CHPL_LLVM')
             self.assertEqual('none', get_var('CHPL_COMM'))
             self.assertEqual('fifo', get_var('CHPL_TASKS'))
             self.assertEqual('none', get_var('CHPL_GMP'))
             self.assertEqual('none', get_var('CHPL_RE2'))
-            self.assertEqual('none', get_var('CHPL_LLVM'))
+            self.assertTrue('none' == got_llvm or 'system' == got_llvm)
             self.assertEqual('cstdlib', get_var('CHPL_MEM'))
 
     def check_scripts(self, shell, source_cmd, path_sep,

third-party/Makefile

@@ -131,17 +131,30 @@ $(LIBUNWIND_INSTALL_DIR): $(LIBUNWIND_DEPEND)
 	rm -rf $(LIBUNWIND_INSTALL_DIR) && rm -rf $(LIBUNWIND_BUILD_DIR)
 	cd libunwind && $(MAKE)
 
-# Check for LLVM_SUPPORT_INSTALL_DIR or LLVM_INSTALL_DIR,
-# depending on the configuration.
-LLVM_CHECK_INSTALL_DIR := $(LLVM_INSTALL_DIR)
-ifeq ($(CHPL_MAKE_LLVM), none)
-  LLVM_CHECK_INSTALL_DIR := $(LLVM_SUPPORT_INSTALL_DIR)
-endif
+ifeq ($(CHPL_MAKE_LLVM), unset)
+# Print the error about needing to set CHPL_LLVM
+llvm: FORCE
+	cd llvm && $(MAKE) unset
+
+else ifeq ($(CHPL_MAKE_LLVM), bundled)
+# build the bundled LLVM
+llvm: $(LLVM_INSTALL_DIR)
+$(LLVM_INSTALL_DIR): $(LLVM_DEPEND)
+	rm -rf $(LLVM_INSTALL_DIR)
+	cd llvm && $(MAKE) llvm
+
+else ifeq ($(CHPL_MAKE_LLVM_SUPPORT), bundled)
+# build the bundled LLVM support library
+llvm: $(LLVM_SUPPORT_INSTALL_DIR)
+$(LLVM_SUPPORT_INSTALL_DIR): $(LLVM_DEPEND)
+	rm -rf $(LLVM_SUPPORT_INSTALL_DIR)
+	cd llvm && $(MAKE) llvm-support
+
+else
 
-llvm: $(LLVM_CHECK_INSTALL_DIR)
-$(LLVM_CHECK_INSTALL_DIR): $(LLVM_DEPEND)
-	rm -rf $(LLVM_CHECK_INSTALL_DIR)
-	cd llvm && $(MAKE) $(CHPL_MAKE_LLVM)
+# nothing to do for CHPL_LLVM=system / CHPL_LLVM_SUPPORT=system
+llvm:
+endif
 
 # Qthreads may use hwloc and/or jemalloc. Ensure they are built first.
 ifeq ($(CHPL_MAKE_HWLOC), bundled)

third-party/llvm/Makefile

@@ -210,14 +210,14 @@ llvm: llvm-config llvm-build llvm-install
 
 llvm-clang: llvm
 
-# to build the LLVM support library even with CHPL_LLVM=none
+# to build the LLVM support library only for use with CHPL_LLVM=none
 llvm-support: llvm-config-support-only llvm-build-support-only llvm-install-support-only
 
 bundled: llvm
 
 system:
 
-none: llvm-support
+none:
 
 unset:
 	@echo "Error: Please set the environment variable CHPL_LLVM to a supported value."

util/chplenv/chpl_llvm.py

@@ -18,8 +18,8 @@ def llvm_versions():
     return ('14','13','12','11',)
 
 @memoize
-def get_uniq_cfg_path_for(llvm_val):
-    if llvm_val == "bundled" or llvm_val == "none":
+def get_uniq_cfg_path_for(llvm_val, llvm_support_val):
+    if llvm_val == "bundled" or llvm_support_val == "bundled":
         # put platform-arch-compiler for included llvm
         llvm_target_dir = chpl_bin_subdir.get('host')
     else:
@@ -31,18 +31,19 @@ def get_uniq_cfg_path_for(llvm_val):
 @memoize
 def get_uniq_cfg_path():
     llvm_val = get()
-    return get_uniq_cfg_path_for(llvm_val)
+    llvm_support_val = get_llvm_support()
+    return get_uniq_cfg_path_for(llvm_val, llvm_support_val)
 
 def get_bundled_llvm_dir():
     chpl_third_party = get_chpl_third_party()
-    llvm_target_dir = get_uniq_cfg_path_for('bundled')
+    llvm_target_dir = get_uniq_cfg_path_for('bundled', 'bundled')
     llvm_subdir = os.path.join(chpl_third_party, 'llvm', 'install',
                                llvm_target_dir)
     return llvm_subdir
 
 def get_bundled_llvm_support_only_dir():
     chpl_third_party = get_chpl_third_party()
-    llvm_target_dir = get_uniq_cfg_path_for('none')
+    llvm_target_dir = get_uniq_cfg_path_for('none', 'bundled')
     llvm_subdir = os.path.join(chpl_third_party, 'llvm', 'install',
                                'support-only-' + llvm_target_dir)
     return llvm_subdir
@@ -51,7 +52,7 @@ def is_included_llvm_built(llvm_val):
     llvm_subdir = None
     if llvm_val == 'bundled':
         llvm_subdir = get_bundled_llvm_dir()
-    elif llvm_val == 'none':
+    else:
         llvm_subdir = get_bundled_llvm_support_only_dir()
 
     llvm_header = os.path.join(llvm_subdir, 'include', 'llvm',
@@ -216,9 +217,35 @@ def find_system_llvm_config():
     return ''
 
 
+# Returns whether to use the bundled or system LLVM for the
+# LLVM support module.
+# This corresponds to the CHPL_LLVM_SUPPORT variable.
+# Since the LLVM support module is now required to build Chapel,
+# this returns "bundled" or "system" even if CHPL_LLVM=none.
+@memoize
+def get_llvm_support():
+    llvm_val = get()
+
+    # If using CHPL_LLVM=bundled or CHPL_LLVM=system
+    # then CHPL_LLVM_SUPPORT needs to match
+    if llvm_val == 'bundled':
+        return 'bundled'
+    if llvm_val == 'system':
+        return 'system'
+
+    llvm_support_val = overrides.get('CHPL_LLVM_SUPPORT')
+    if not llvm_support_val:
+        if has_compatible_installed_llvm():
+            llvm_support_val = 'system'
+        else:
+            llvm_support_val = 'bundled'
+
+    return llvm_support_val
+
 @memoize
 def get_llvm_config():
     llvm_val = get()
+    llvm_support_val = get_llvm_support()
     llvm_config = overrides.get('CHPL_LLVM_CONFIG', 'none')
 
     if llvm_val == 'bundled':
@@ -228,18 +255,20 @@ def get_llvm_config():
             warning("CHPL_LLVM_CONFIG is ignored for CHPL_LLVM=bundled")
         llvm_config = bundled_config
 
-    elif llvm_val == 'none':
+    elif llvm_support_val == 'bundled':
         llvm_subdir = get_bundled_llvm_support_only_dir()
         bundled_config = os.path.join(llvm_subdir, 'bin', 'llvm-config')
         if llvm_config != 'none' and llvm_config != bundled_config:
-            warning("CHPL_LLVM_CONFIG is ignored for CHPL_LLVM=none")
+            warning("CHPL_LLVM_CONFIG is ignored for CHPL_LLVM_SUPPORT=bundled")
         llvm_config = bundled_config
 
-    elif llvm_config == 'none' and llvm_val == 'system':
-        llvm_config = find_system_llvm_config()
+    elif llvm_config == 'none':
+        if llvm_val == 'system' or llvm_support_val == 'system':
+            llvm_config = find_system_llvm_config()
 
     return llvm_config
 
+
 @memoize
 def get_llvm_version():
     (llvm_version, _) = check_llvm_config(get_llvm_config())
@@ -248,6 +277,7 @@ def get_llvm_version():
 @memoize
 def validate_llvm_config():
     llvm_val = get()
+    llvm_support_val = get_llvm_support()
     llvm_config = get_llvm_config()
 
     if llvm_val == 'system':
@@ -256,6 +286,12 @@ def validate_llvm_config():
                   " with one of the supported versions: {0}".format(
                   llvm_versions_string()))
 
+    if llvm_support_val == 'system':
+        if llvm_config == '' or llvm_config == 'none':
+            error("CHPL_LLVM_SUPPORT=system but could not find an installed "
+                  "LLVM with one of the supported versions: {0}".format(
+                  llvm_versions_string()))
+
     if (llvm_val == 'system' or
         (llvm_val == 'bundled' and os.path.exists(llvm_config))):
         version, config_error = check_llvm_config(llvm_config)
@@ -363,6 +399,11 @@ def has_compatible_installed_llvm():
     # otherwise, something went wrong, so return False
     return False
 
+# Returns the setting to use for CHPL_LLVM
+#  CHPL_LLVM=none means build the compiler without enabling LLVM and clang
+#                 integration (but note the LLVM support library is still used)
+#  CHPL_LLVM=system means to use a system install of LLVM and clang
+#  CHPL_LLVM=bundled means to use the bundled version of LLVM and clang
 @memoize
 def get():
     llvm_val = overrides.get('CHPL_LLVM')
@@ -726,9 +767,14 @@ def get_host_compile_args():
     system = [ ]
 
     llvm_val = get()
+    llvm_support_val = get_llvm_support()
     llvm_config = get_llvm_config()
 
-    if llvm_val == 'system':
+    # quit early if the llvm value is unset
+    if llvm_val == 'unset':
+        return (bundled, system)
+
+    if llvm_support_val == 'system':
         # On Mac OS X with Homebrew, apply a workaround for issue #19217.
         # This avoids finding headers in the libc++ installed by llvm@12 e.g.
         if use_system_libcxx_workaround():
@@ -748,9 +794,7 @@ def get_host_compile_args():
         cxxflags = run_command([llvm_config, '--cxxflags'])
         system.extend(filter_llvm_config_flags(cxxflags.split()))
 
-    elif llvm_val == 'bundled' or llvm_val == 'none':
-        # none is handled here to get the LLVMSupport library
-
+    elif llvm_support_val == 'bundled':
         # don't try to run llvm-config if it's not built yet
         if is_included_llvm_built(llvm_val):
             # Note, the cxxflags should include the -I for the include dir
@@ -774,6 +818,7 @@ def get_host_link_args():
 
     llvm_dynamic = True
     llvm_val = get()
+    llvm_support_val = get_llvm_support()
     llvm_config = get_llvm_config()
     clang_static_libs = ['-lclangFrontend',
                          '-lclangSerialization',
@@ -799,12 +844,16 @@ def get_host_link_args():
                        'coroutines',
                        'lto']
 
+    # quit early if the llvm value is unset
+    if llvm_val == 'unset':
+        return (bundled, system)
+
     # only use LLVMSupport for CHPL_LLVM=none
     if llvm_val == 'none':
         clang_static_libs = [ ]
         llvm_components = ['support']
 
-    if llvm_val == 'system':
+    if llvm_support_val == 'system':
         # On Mac OS X with Homebrew, apply a workaround for issue #19217.
         # This avoids linking with the libc++ installed by llvm@12 e.g.
         if use_system_libcxx_workaround():
@@ -846,9 +895,7 @@ def get_host_link_args():
             system.extend(filter_llvm_link_flags(ldflags.split()))
 
 
-    elif llvm_val == 'bundled' or llvm_val == 'none':
-        # none is handled here to use the LLVM Support library
-
+    elif llvm_support_val == 'bundled':
         # Link statically for now for the bundled configuration
         # If this changes in the future:
         # * check for problems finding libstdc++ with different PrgEnv compilers
@@ -927,6 +974,10 @@ def _main():
     parser.add_option('--sdkroot', dest='action',
                       action='store_const',
                       const='sdkroot', default='')
+    parser.add_option('--quickstart', dest='action',
+                      action='store_const',
+                      const='quickstart', default='')
+
 
 
     (options, args) = parser.parse_args()
@@ -946,6 +997,11 @@ def _main():
         sys.stdout.write("{0}\n".format(llvm_versions))
     elif options.action == 'sdkroot':
         sys.stdout.write("{0}\n".format(get_clang_args_sdkroot()))
+    elif options.action == 'quickstart':
+        if has_compatible_installed_llvm():
+            sys.stdout.write("system\n")
+        else:
+            sys.stdout.write("none\n")
     else:
         sys.stdout.write("{0}\n".format(llvm_val))
 

util/chplenv/printchplenv.py

@@ -114,6 +114,7 @@
     ChapelEnv('CHPL_RE2', RUNTIME | DEFAULT, 're2'),
     ChapelEnv('  CHPL_RE2_IS_OVERRIDDEN', INTERNAL),
     ChapelEnv('CHPL_LLVM', COMPILER | DEFAULT, 'llvm'),
+    ChapelEnv('  CHPL_LLVM_SUPPORT', COMPILER | NOPATH, 'llvm'),
     ChapelEnv('  CHPL_LLVM_CONFIG', COMPILER | NOPATH),
     ChapelEnv('  CHPL_LLVM_VERSION', COMPILER),
     ChapelEnv('  CHPL_LLVM_CLANG_C', INTERNAL),
@@ -204,6 +205,7 @@ def compute_all_values():
     ENV_VALS['CHPL_RE2'] = chpl_re2.get()
     ENV_VALS['  CHPL_RE2_IS_OVERRIDDEN'] = chpl_re2.is_overridden()
     ENV_VALS['CHPL_LLVM'] = chpl_llvm.get()
+    ENV_VALS['  CHPL_LLVM_SUPPORT'] = chpl_llvm.get_llvm_support()
     ENV_VALS['  CHPL_LLVM_CONFIG'] = chpl_llvm.get_llvm_config()
     ENV_VALS['  CHPL_LLVM_VERSION'] = chpl_llvm.get_llvm_version()
     llvm_clang_c = chpl_llvm.get_llvm_clang('c')
@@ -318,10 +320,6 @@ def filter_tidy(chpl_env):
         return comm == 'ofi'
     elif chpl_env.name == '  CHPL_NETWORK_ATOMICS':
         return comm != 'none'
-    elif chpl_env.name == '  CHPL_LLVM_CONFIG':
-        return llvm != 'none'
-    elif chpl_env.name == '  CHPL_LLVM_VERSION':
-        return llvm != 'none'
     elif chpl_env.name == '  CHPL_CUDA_PATH':
         return locale_model == 'gpu'
     elif chpl_env.name == '  CHPL_CUDA_LIBDEVICE_PATH':

util/quickstart/setchplenv.bash

@@ -64,5 +64,6 @@ export CHPL_GMP=none
 echo "Setting CHPL_RE2 to none"
 export CHPL_RE2=none
 
-echo "Setting CHPL_LLVM to none"
-export CHPL_LLVM=none
+USE_LLVM=`$CHPL_PYTHON $chpl_home/util/chplenv/chpl_llvm.py --quickstart`
+echo "Setting CHPL_LLVM to $USE_LLVM"
+export CHPL_LLVM=$USE_LLVM

util/quickstart/setchplenv.csh

@@ -53,5 +53,6 @@ setenv CHPL_GMP none
 echo "Setting CHPL_RE2 to none"
 setenv CHPL_RE2 none
 
-echo "Setting CHPL_LLVM to none"
-setenv CHPL_LLVM none
+set USE_LLVM = `$CHPL_PYTHON "$CHPL_HOME"/util/chplenv/chpl_llvm.py --quickstart`
+echo "Setting CHPL_LLVM to $USE_LLVM"
+setenv CHPL_LLVM $USE_LLVM

util/quickstart/setchplenv.fish

@@ -57,5 +57,6 @@ set -x CHPL_GMP none
 echo "Setting CHPL_RE2 to none"
 set -x CHPL_RE2 none
 
-echo "Setting CHPL_LLVM to none"
-set -x CHPL_LLVM none
+set -x USE_LLVM (eval "$CHPL_PYTHON" "$CHPL_HOME/util/chplenv/chpl_llvm.py" "--quickstart")
+echo "Setting CHPL_LLVM to $USE_LLVM"
+set -x CHPL_LLVM $USE_LLVM

util/quickstart/setchplenv.sh

@@ -75,8 +75,9 @@ export CHPL_RE2
 echo "                           ...none"
 echo " "
 
+USE_LLVM=`$CHPL_PYTHON "$CHPL_HOME"/util/chplenv/chpl_llvm.py --quickstart`
 echo "Setting CHPL_LLVM to..."
-CHPL_LLVM=none
+CHPL_LLVM=$USE_LLVM
 export CHPL_LLVM
-echo "                           ...none"
+echo "                           ...$USE_LLVM"
 echo " "