From d362b91fa655fb02a4214e28eb33b8b60a0e1ace Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Mon, 4 Oct 2021 14:24:07 +0200 Subject: [PATCH] avoid hardreg autoinit This avoids initializating "uninitialized" hardregs like SP. 2021-10-04 Richard Biener * gimplify.c (is_var_need_auto_init): DECL_HARD_REGISTER variables are not to be initialized. * gcc.dg/auto-init-hardreg-1.c: New testcase. --- gcc/gimplify.c | 2 ++ gcc/testsuite/gcc.dg/auto-init-hardreg-1.c | 9 +++++++++ 2 files changed, 11 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/auto-init-hardreg-1.c diff --git a/gcc/gimplify.c b/gcc/gimplify.c index f4bc649632ec..b27776af7c8a 100644 --- a/gcc/gimplify.c +++ b/gcc/gimplify.c @@ -1825,6 +1825,8 @@ static bool is_var_need_auto_init (tree decl) { if (auto_var_p (decl) + && (TREE_CODE (decl) != VAR_DECL + || !DECL_HARD_REGISTER (decl)) && (flag_auto_var_init > AUTO_INIT_UNINITIALIZED) && (!lookup_attribute ("uninitialized", DECL_ATTRIBUTES (decl))) && !is_empty_type (TREE_TYPE (decl))) diff --git a/gcc/testsuite/gcc.dg/auto-init-hardreg-1.c b/gcc/testsuite/gcc.dg/auto-init-hardreg-1.c new file mode 100644 index 000000000000..7c9de99bf056 --- /dev/null +++ b/gcc/testsuite/gcc.dg/auto-init-hardreg-1.c @@ -0,0 +1,9 @@ +/* { dg-do run { target i?86-*-* x86_64-*-* } } */ +/* { dg-options "-ftrivial-auto-var-init=zero" } */ + +int +main () +{ + register long *sp __asm__("sp"); + return 0; +} -- 2.47.2