This is the mail archive of the mailing list for the GCC project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[patch RFA] Handle blockage insn in mode-switching.c/create_pre_exit


The mainline fails to build for sh-elf and sh4-unknown-linux-gnu
during the compilation of libgcc2.c:

It started to fail after the patch

r126403 | uros | 2007-07-06 17:53:15 +0900 (Fri, 06 Jul 2007) | 13 lines

        PR rtl_optimization/32450
        * function.c (thread_prologue_and_epilogue_insns): Emit blockage insn
        to ensure that instructions are not moved into the prologue when
        profiling is on.  Remove unused prologue_end variable.
        (expand_function_end): Emit blockage insn instead of ASM_INPUT rtx
        as a scheduling barrier.

The function mode-switching.c:create_pre_exit skipped the above
scheduling barrier when scanning the insns:

Now ASM_INPUT rtx is replaced with a real blockage insn, we
should skip this blockage insn.  The attached patch fixes
the build failure for sh-elf and sh4-unknown-linux-gnu.
It's tested with bootstrap and regtested with the top level
"make -k check" on i686-pc-linux-gnu with no new failures.

:ADDPATCH rtl-optimization:

2007-07-08  Kaz Kojima  <>

	PR target/32664
	* mode-switching.c: Skip blockage insn instead of ASM_INPUT rtx.

--- ORIG/trunk/gcc/mode-switching.c	2007-06-12 09:34:43.000000000 +0900
+++ LOCAL/trunk/gcc/mode-switching.c	2007-07-07 18:31:46.000000000 +0900
@@ -209,6 +209,7 @@ create_pre_exit (int n_entities, int *en
   edge eg;
   edge_iterator ei;
   basic_block pre_exit;
+  rtx blockage_insn = gen_blockage ();
   /* The only non-call predecessor at this stage is a block with a
      fallthrough edge; there can be at most one, but there could be
@@ -255,8 +256,7 @@ create_pre_exit (int n_entities, int *en
 			last_insn = return_copy;
-		    if (GET_CODE (PATTERN (return_copy)) == ASM_INPUT
-			&& strcmp (XSTR (PATTERN (return_copy), 0), "") == 0)
+		    if (rtx_equal_p (PATTERN (return_copy), blockage_insn))
 			last_insn = return_copy;

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]