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| author | Richard Guenther <rguenther@suse.de> | 2011-07-22 11:55:30 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2011-07-22 11:55:30 +0000 |
| commit | 27315aa68fbb97cc8cbb71da2ca54b9e8052b057 (patch) | |
| tree | ca416cca45b476a17521ae6b9a7c39a71007f976 /gcc | |
| parent | 679debeea3913242cd756be013e329ed8ab92af4 (diff) | |
| download | gcc-27315aa68fbb97cc8cbb71da2ca54b9e8052b057.zip gcc-27315aa68fbb97cc8cbb71da2ca54b9e8052b057.tar.gz gcc-27315aa68fbb97cc8cbb71da2ca54b9e8052b057.tar.bz2 | |
re PR middle-end/45819 (unexpected unaligned access to volatile int)
2011-07-22 Richard Guenther <rguenther@suse.de>
PR tree-optimization/45819
* tree-ssa-forwprop.c (forward_propagate_addr_expr_1): Properly
preserve volatile and notrap flags.
* gcc.dg/pr45819.c: New testcase.
From-SVN: r176623
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr45819.c | 20 | ||||
| -rw-r--r-- | gcc/tree-ssa-forwprop.c | 8 |
4 files changed, 37 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index dfba411..cb9c3ae 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2011-07-22 Richard Guenther <rguenther@suse.de> + + PR tree-optimization/45819 + * tree-ssa-forwprop.c (forward_propagate_addr_expr_1): Properly + preserve volatile and notrap flags. + 2011-07-22 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> Ralf Wildenhues <Ralf.Wildenhues@gmx.de> diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index bae0698..d4f641e 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2011-07-22 Richard Guenther <rguenther@suse.de> + + PR tree-optimization/45819 + * gcc.dg/pr45819.c: New testcase. + 2011-07-22 Uros Bizjak <ubizjak@gmail.com> * lib/target-supports.exp (check_ifunc_available): Rewrite. diff --git a/gcc/testsuite/gcc.dg/pr45819.c b/gcc/testsuite/gcc.dg/pr45819.c new file mode 100644 index 0000000..de96800 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr45819.c @@ -0,0 +1,20 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + +struct ehci_regs { + char x; + unsigned int port_status[0]; +} __attribute__ ((packed)); + +struct ehci_hcd { + struct ehci_regs *regs; +}; + +int ehci_hub_control (struct ehci_hcd *ehci, int wIndex) +{ + unsigned int *status_reg = &ehci->regs->port_status[wIndex]; + return *(volatile unsigned int *)status_reg; +} + +/* { dg-final { scan-tree-dump "={v}" "optimized" } } */ +/* { dg-final { cleanup-tree-dump "optimized" } } */ diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index c08cb18..40db928 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -875,6 +875,8 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, } *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), new_base, new_offset); + TREE_THIS_VOLATILE (*def_rhs_basep) = TREE_THIS_VOLATILE (lhs); + TREE_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (lhs); gimple_assign_set_lhs (use_stmt, unshare_expr (TREE_OPERAND (def_rhs, 0))); *def_rhs_basep = saved; @@ -927,9 +929,9 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, tidy_after_forward_propagate_addr (use_stmt); return res; } - /* If the LHS is a plain dereference and the value type is the same as + /* If the RHS is a plain dereference and the value type is the same as that of the pointed-to type of the address we can put the - dereferenced address on the LHS preserving the original alias-type. */ + dereferenced address on the RHS preserving the original alias-type. */ else if (gimple_assign_rhs1 (use_stmt) == rhs && useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (use_stmt)), @@ -954,6 +956,8 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, } *def_rhs_basep = build2 (MEM_REF, TREE_TYPE (*def_rhs_basep), new_base, new_offset); + TREE_THIS_VOLATILE (*def_rhs_basep) = TREE_THIS_VOLATILE (rhs); + TREE_THIS_NOTRAP (*def_rhs_basep) = TREE_THIS_NOTRAP (rhs); gimple_assign_set_rhs1 (use_stmt, unshare_expr (TREE_OPERAND (def_rhs, 0))); *def_rhs_basep = saved; |