LoongArch: Add vector calling convention support

.b4-config

@@ -0,0 +1,4 @@
+[b4]
+    midmask = https://inbox.sourceware.org/%s
+    linkmask = https://inbox.sourceware.org/%s
+    send-series-to = gcc-patches@gcc.gnu.org

.dir-locals.el

@@ -18,6 +18,10 @@
 	      (tcl-continued-indent-level . 4)
 	      (indent-tabs-mode . t)))
  (nil . ((bug-reference-url-format . "https://gcc.gnu.org/PR%s")))
+ ;; Please keep C and C++ in sync.
  (c-mode . ((c-file-style . "GNU")
 	    (indent-tabs-mode . t)
-	    (fill-column . 79))))
+	    (fill-column . 79)))
+ (c++-mode . ((c-file-style . "GNU")
+	      (indent-tabs-mode . t)
+	      (fill-column . 79))))

.forgejo/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,9 @@
+Thanks for taking the time to contribute to GCC!
+
+Please be advised that https://forge.sourceware.org/ is currently a trial
+that is being used by the GCC community to experiment with a new workflow
+based on pull requests.
+
+Pull requests sent here may be forgotten or ignored. Patches that you want to
+propose for inclusion in GCC should use the existing email-based workflow,
+see https://gcc.gnu.org/contribute.html

.gitignore

@@ -38,6 +38,7 @@ cscope.out
 
 .local.vimrc
 .lvimrc
+.vscode
 
 .clang-format
 .clang-tidy
@@ -70,3 +71,6 @@ stamp-*
 /gmp*
 /isl*
 /gettext*
+
+# ADDITIONS from GCCRS front-end
+libgrust/*/target/