[clang-c] introduce queries on GCC-style inline assembly statements (#143424)

[Discourse
link](https://discourse.llvm.org/t/a-small-proposal-for-extraction-of-inline-assembly-block-information/86658)

We strive for exposing such information using existing stable ABIs. In
doing so, queries are limited to what the original source holds or the
LLVM IR `asm` block would expose in connection with attributes that the
queries are concerned.

These APIs opens new opportunities for `rust-bindgen` to translate
inline assemblies in reasonably cases into Rust inline assembly blocks,
which would further aid better interoperability with other existing
code.

---------

Signed-off-by: Xiangfei Ding <dingxiangfei2009@protonmail.ch>

1 files changed, 50 insertions, 0 deletions

diff --git a/clang/tools/c-index-test/c-index-test.c b/clang/tools/c-index-test/c-index-test.c
index 4a887cd..cb32457 100644
--- a/clang/tools/c-index-test/c-index-test.c
+++ b/clang/tools/c-index-test/c-index-test.c
@@ -1989,6 +1989,51 @@ static enum CXChildVisitResult PrintDeclAttributes(CXCursor cursor, CXCursor p,
 }
 
 /******************************************************************************/
+/* Inline assembly cursor testing                                             */
+/******************************************************************************/
+
+static enum CXChildVisitResult
+PrintGCCInlineAssembly(CXCursor cursor, CXCursor p, CXClientData d) {
+  CXString Constraint, Template, Clobber;
+  CXCursor Expr;
+  unsigned hasGoto, i, e;
+  if (clang_getCursorKind(cursor) != CXCursor_AsmStmt)
+    return CXChildVisit_Recurse;
+
+  hasGoto = clang_Cursor_isGCCAssemblyHasGoto(cursor);
+  printf("===ASM TEMPLATE%s===\n", hasGoto ? " (WITH GOTO)" : "");
+  Template = clang_Cursor_getGCCAssemblyTemplate(cursor);
+  printf("%s", clang_getCString(Template));
+  clang_disposeString(Template);
+  printf("\n===ASM TEMPLATE END===\n");
+
+  printf("volatile: %s\n",
+         clang_Cursor_isGCCAssemblyVolatile(cursor) ? "true" : "false");
+
+  for (i = 0, e = clang_Cursor_getGCCAssemblyNumOutputs(cursor); i < e; ++i) {
+    clang_Cursor_getGCCAssemblyOutput(cursor, i, &Constraint, &Expr);
+    printf("Output #%d Constraint (%s): ", i, clang_getCString(Constraint));
+    PrintCursor(Expr, NULL);
+    printf("\n");
+    clang_disposeString(Constraint);
+  }
+  for (i = 0, e = clang_Cursor_getGCCAssemblyNumInputs(cursor); i < e; ++i) {
+    clang_Cursor_getGCCAssemblyInput(cursor, i, &Constraint, &Expr);
+    printf("Input #%d Constraint (%s): ", i, clang_getCString(Constraint));
+    PrintCursor(Expr, NULL);
+    printf("\n");
+    clang_disposeString(Constraint);
+  }
+  for (i = 0, e = clang_Cursor_getGCCAssemblyNumClobbers(cursor); i < e; ++i) {
+    Clobber = clang_Cursor_getGCCAssemblyClobber(cursor, i);
+    printf("Clobber #%d: %s\n", i, clang_getCString(Clobber));
+    clang_disposeString(Clobber);
+  }
+  printf("===ASM END===\n");
+  return CXChildVisit_Recurse;
+}
+
+/******************************************************************************/
 /* Target information testing.                                                */
 /******************************************************************************/
 
@@ -5010,6 +5055,7 @@ static void print_usage(void) {
     "       c-index-test -test-annotate-tokens=<range> {<args>}*\n"
     "       c-index-test -test-inclusion-stack-source {<args>}*\n"
     "       c-index-test -test-inclusion-stack-tu <AST file>\n");
+  fprintf(stderr, "       c-index-test -test-inline-assembly <AST file>\n");
   fprintf(stderr,
     "       c-index-test -test-print-linkage-source {<args>}*\n"
     "       c-index-test -test-print-visibility {<args>}*\n"
@@ -5167,6 +5213,10 @@ int cindextest_main(int argc, const char **argv) {
   else if (argc > 2 && strstr(argv[1], "-single-symbol-sgf-for=") == argv[1])
     return perform_test_single_symbol_sgf(argv[1], argc - 2, argv + 2);
 
+  if (argc > 2 && strstr(argv[1], "-test-inline-assembly") == argv[1])
+    return perform_test_load_source(argc - 2, argv + 2, "all",
+                                    PrintGCCInlineAssembly, NULL);
+
   print_usage();
   return 1;
 }