[PATCH] PR33661 Fix problem with register asm in templates

[Andreas Krebbel]

Hi,

register asm declarations currently don't work when being expanded as
part of a function template.

There appeared to be two problems:

1. When parsing a template function cp_finish_decl returns before the
asmspec is set in the var decl.
2. When expanding the template function the assembler_name is zeroed
out.

Bootstrapped and regtested on x86_64 and s390x.

Ok?

Bye,

-Andreas-

2015-06-11  Andreas Krebbel  <kreb...@linux.vnet.ibm.com>

        PR C++/33661
        * gcc/cp/decl.c (cp_finish_decl): Set assembler name for register
        asm constructs.
        * gcc/cp/pt.c (tsubst_decl): Do not zero out the assembler name
        for register asm constructs.

2015-06-11  Andreas Krebbel  <kreb...@linux.vnet.ibm.com>

        PR C++/33661
        * gcc.target/s390/pr33661.cc: New test.
        * gcc.target/s390/s390.exp: Run also tests with .cc suffix.


diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index a8cb358..b1eb33d 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -6536,6 +6536,13 @@ cp_finish_decl (tree decl, tree init, bool 
init_const_expr_p,
 
       if (init)
        DECL_INITIAL (decl) = init;
+
+      /* Set the DECL_ASSEMBLER_NAME for the object.  */
+      if (asmspec && VAR_P (decl) && DECL_REGISTER (decl))
+       {
+         set_user_assembler_name (decl, asmspec);
+         DECL_HARD_REGISTER (decl) = 1;
+       }
       return;
     }
 
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index a0c5d7c..74ec5dd 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -11384,7 +11384,8 @@ tsubst_decl (tree t, tree args, tsubst_flags_t complain)
        cp_apply_type_quals_to_decl (cp_type_quals (type), r);
        DECL_CONTEXT (r) = ctx;
        /* Clear out the mangled name and RTL for the instantiation.  */
-       SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
+       if (!VAR_P (r) || !DECL_HARD_REGISTER (r))
+         SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
        if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
          SET_DECL_RTL (r, NULL);
        /* The initializer must not be expanded until it is required;
diff --git a/gcc/testsuite/gcc.target/s390/pr33661.cc 
b/gcc/testsuite/gcc.target/s390/pr33661.cc
new file mode 100644
index 0000000..7070e56
--- /dev/null
+++ b/gcc/testsuite/gcc.target/s390/pr33661.cc
@@ -0,0 +1,21 @@
+/* PR c++/33661  */
+
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+/* { dg-final { scan-assembler "reg: %r3" } } */
+
+typedef unsigned long long int uint64_t;
+
+template < typename T > static inline void
+bar (T c)
+{
+  int a;
+  register unsigned long b __asm__ ("r3") = (unsigned long)&a;
+  __asm__ volatile ("reg: %0" : : "d" (b):);
+}
+
+void
+foo (uint64_t c)
+{
+  bar (c);
+}
diff --git a/gcc/testsuite/gcc.target/s390/s390.exp 
b/gcc/testsuite/gcc.target/s390/s390.exp
index 0b8f80ed..edef574 100644
--- a/gcc/testsuite/gcc.target/s390/s390.exp
+++ b/gcc/testsuite/gcc.target/s390/s390.exp
@@ -64,7 +64,7 @@ dg-init
 set hotpatch_tests $srcdir/$subdir/hotpatch-\[0-9\]*.c
 
 # Main loop.
-dg-runtest [lsort [prune [glob -nocomplain $srcdir/$subdir/*.\[cS\]] \
+dg-runtest [lsort [prune [glob -nocomplain $srcdir/$subdir/*.\{\[cS\],cc\}] \
                         $hotpatch_tests]] "" $DEFAULT_CFLAGS
 
 dg-runtest [lsort [glob -nocomplain $srcdir/$subdir/*vector*/*.\[cS\]]] \