libgccjit: Add support for setting the link section of global variables [PR100688]

2021-12-12  Antoni Boucher  <bouanto@zoho.com>

gcc/jit/
	PR target/100688
	* docs/topics/compatibility.rst (LIBGCCJIT_ABI_18): New ABI
	tag.
	* docs/topics/expressions.rst: Add documentation for the
	function gcc_jit_lvalue_set_link_section.
	* jit-playback.h: New function (set_link_section).
	* jit-recording.c: New function (set_link_section) and
	support for setting the link section.
	* jit-recording.h: New function (set_link_section) and new
	field m_link_section.
	* libgccjit.c: New function (gcc_jit_lvalue_set_link_section).
	* libgccjit.h: New function (gcc_jit_lvalue_set_link_section).
	* libgccjit.map (LIBGCCJIT_ABI_18): New ABI tag.

gcc/testsuite/
	PR target/100688
	* jit.dg/all-non-failing-tests.h: Mention new test
	link-section-assembler.
	* jit.dg/test-link-section-assembler.c: New test.
	* jit.dg/jit.exp: New helper function to test that the
	assembly contains a pattern.

3 files changed, 73 insertions, 0 deletions

diff --git a/gcc/testsuite/jit.dg/all-non-failing-tests.h b/gcc/testsuite/jit.dg/all-non-failing-tests.h
index 350a30b..3e8ccbc 100644
--- a/gcc/testsuite/jit.dg/all-non-failing-tests.h
+++ b/gcc/testsuite/jit.dg/all-non-failing-tests.h
@@ -209,6 +209,9 @@
 #undef create_code
 #undef verify_code
 
+/* test-link-section-assembler.c: This can't be in the testcases array as it
+   doesn't have a verify_code implementation.  */
+
 /* test-linked-list.c */
 #define create_code create_code_linked_list
 #define verify_code verify_code_linked_list
diff --git a/gcc/testsuite/jit.dg/jit.exp b/gcc/testsuite/jit.dg/jit.exp
index 10b98bd..3568dbb 100644
--- a/gcc/testsuite/jit.dg/jit.exp
+++ b/gcc/testsuite/jit.dg/jit.exp
@@ -864,6 +864,39 @@ proc jit-verify-assembler { args } {
     jit-run-executable ${executable_from_asm} ${dg-output-text}
 }
 
+# Assuming that a .s file has been written out named
+# OUTPUT_FILENAME, check that the argument matches the
+# output file.
+# For use by the test-link-section-assembler.c testcase.
+proc jit-verify-assembler-output { args } {
+    verbose "jit-verify-assembler: $args"
+
+    set dg-output-text [lindex $args 0]
+    verbose "dg-output-text: ${dg-output-text}"
+
+    upvar 2 name name
+    verbose "name: $name"
+
+    upvar 2 prog prog
+    verbose "prog: $prog"
+    set asm_filename [jit-get-output-filename $prog]
+    verbose "  asm_filename: ${asm_filename}"
+
+    # Read the assembly file.
+    set f [open $asm_filename r]
+    set content [read $f]
+    close $f
+
+    # Verify that the assembly matches the regex.
+    if { ![regexp ${dg-output-text} $content] } {
+	fail "${asm_filename} output pattern test, is ${content}, should match ${dg-output-text}"
+	verbose "Failed test for output pattern ${dg-output-text}" 3
+    } else {
+	pass "${asm_filename} output pattern test, ${dg-output-text}"
+	verbose "Passed test for output pattern ${dg-output-text}" 3
+    }
+
+}
 # Assuming that a .o file has been written out named
 # OUTPUT_FILENAME, invoke the driver to try to turn it into
 # an executable, and try to run the result.
diff --git a/gcc/testsuite/jit.dg/test-link-section-assembler.c b/gcc/testsuite/jit.dg/test-link-section-assembler.c
new file mode 100644
index 0000000..a90b00e
--- /dev/null
+++ b/gcc/testsuite/jit.dg/test-link-section-assembler.c
@@ -0,0 +1,37 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "libgccjit.h"
+
+#define TEST_COMPILING_TO_FILE
+#define OUTPUT_KIND      GCC_JIT_OUTPUT_KIND_ASSEMBLER
+#define OUTPUT_FILENAME  "output-of-test-link-section-assembler.c.s"
+#include "harness.h"
+
+void
+create_code (gcc_jit_context *ctxt, void *user_data)
+{
+  /* Let's try to inject the equivalent of:
+     int foo __attribute__((section(".section")));
+  */
+  gcc_jit_type *int_type =
+    gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_INT);
+  gcc_jit_lvalue *foo =
+    gcc_jit_context_new_global (
+      ctxt, NULL, GCC_JIT_GLOBAL_EXPORTED, int_type, "foo");
+  gcc_jit_lvalue_set_link_section(foo, ".my_section");
+
+  gcc_jit_function *func_main =
+    gcc_jit_context_new_function (ctxt, NULL,
+				  GCC_JIT_FUNCTION_EXPORTED,
+				  int_type,
+				  "main",
+				  0, NULL,
+				  0);
+  gcc_jit_rvalue *zero = gcc_jit_context_zero (ctxt, int_type);
+  gcc_jit_block *block = gcc_jit_function_new_block (func_main, NULL);
+  gcc_jit_block_end_with_return (block, NULL, zero);
+}
+
+/* { dg-final { jit-verify-output-file-was-created "" } } */
+/* { dg-final { jit-verify-assembler-output ".section	.my_section" } } */