From d0e4968c33c257bcfa1afa4f499661c18c80e5bc Mon Sep 17 00:00:00 2001 From: David Daney Date: Fri, 4 Dec 2009 17:46:23 +0000 Subject: [PATCH] re PR rtl-optimization/42164 (internal compiler error: in simplify_subreg, at simplify-rtx.c:5138) 2009-12-04 David Daney PR rtl-optimization/42164 * combine.c (combine_simplify_rtx): Handle truncation of integer constants. 2009-12-04 David Daney PR rtl-optimization/42164 * gcc.c-torture/compile/pr42164.c: New test. From-SVN: r154987 --- gcc/ChangeLog | 6 +++++ gcc/combine.c | 4 +++ gcc/testsuite/ChangeLog | 5 ++++ gcc/testsuite/gcc.c-torture/compile/pr42164.c | 25 +++++++++++++++++++ 4 files changed, 40 insertions(+) create mode 100644 gcc/testsuite/gcc.c-torture/compile/pr42164.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 450d54d6274..f01968c789c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2009-12-04 David Daney + + PR rtl-optimization/42164 + * combine.c (combine_simplify_rtx): Handle truncation of integer + constants. + 2009-12-04 Richard Guenther * lto-streamer-out.c (pack_ts_decl_common_value_fields): diff --git a/gcc/combine.c b/gcc/combine.c index cdc677d17c7..7f3f6da2cea 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -5156,6 +5156,10 @@ combine_simplify_rtx (rtx x, enum machine_mode op0_mode, int in_dest) force_to_mode (XEXP (x, 0), GET_MODE (XEXP (x, 0)), GET_MODE_MASK (mode), 0)); + /* We can truncate a constant value and return it. */ + if (CONST_INT_P (XEXP (x, 0))) + return gen_int_mode (INTVAL (XEXP (x, 0)), mode); + /* Similarly to what we do in simplify-rtx.c, a truncate of a register whose value is a comparison can be replaced with a subreg if STORE_FLAG_VALUE permits. */ diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 577d18b2163..b20ddd2fdcf 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2009-12-04 David Daney + + PR rtl-optimization/42164 + * gcc.c-torture/compile/pr42164.c: New test. + 2009-12-04 Eric Botcazou * gnat.dg/specs/size_attribute1.ads: New test. diff --git a/gcc/testsuite/gcc.c-torture/compile/pr42164.c b/gcc/testsuite/gcc.c-torture/compile/pr42164.c new file mode 100644 index 00000000000..7b94aefe7d8 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/pr42164.c @@ -0,0 +1,25 @@ +typedef struct +{ + unsigned long long pte; +} pte_t; +pte_t mk_swap_pte (unsigned long offset) +{ + pte_t pte; + pte.pte = (offset << 40); + return pte; +} +int pte_file (pte_t pte) +{ + return pte.pte & (1 << 4); +} +typedef struct +{ + unsigned long val; +} swp_entry_t; +pte_t swp_entry_to_pte (swp_entry_t entry) +{ + swp_entry_t arch_entry; + arch_entry = (swp_entry_t){mk_swap_pte (swp_offset (entry)).pte}; + __BUG_ON ((unsigned long) pte_file ((pte_t) {arch_entry.val})); + return (pte_t) {arch_entry.val}; +}