The patch 2011-05-26 Richard Guenther <rguenther@suse.de> * fold-const.c (fold_unary_loc): Remove bogus code. has introduced an infinite recursion in the constant folder for the Ada testcase about to be attached. No change after the fix for PR middle-end/49177.
Created attachment 24367 [details] Concatenated testcase Run gnatchop on the file. Suitable for inclusion in the gnat.dg testsuite.
Confirmed. Endlessly visiting Breakpoint 6, fold_unary_loc (loc=0, code=TRUTH_NOT_EXPR, type=0x7ffff5b7e5e8, op0=0x7ffff5b820a0) at /space/rguenther/src/svn/trunk/gcc/fold-const.c:7555 7555 enum tree_code_class kind = TREE_CODE_CLASS (code); (gdb) call debug_generic_expr (op0) (const boolean) ((boolean) ((system__unsigned_types__short_unsigned) v->OBJECT >> (integer) i) & 1) Breakpoint 6, fold_unary_loc (loc=0, code=NOP_EXPR, type=0x7ffff5b7e5e8, op0=0x7ffff5b83000) at /space/rguenther/src/svn/trunk/gcc/fold-const.c:7555 7555 enum tree_code_class kind = TREE_CODE_CLASS (code); (gdb) call debug_generic_expr (op0) ((boolean) ((system__unsigned_types__short_unsigned) v->OBJECT >> (integer) i) & 1) == 0 (gdb) call debug_generic_expr (type) const boolean Breakpoint 7, fold_binary_loc (loc=0, code=EQ_EXPR, type=0x7ffff5b7e5e8, op0=0x7ffff5b72e70, op1=0x7ffff7ee85e0) at /space/rguenther/src/svn/trunk/gcc/fold-const.c:9280 9280 enum tree_code_class kind = TREE_CODE_CLASS (code); (gdb) call debug_generic_expr (op0) (boolean) ((system__unsigned_types__short_unsigned) v->OBJECT >> (integer) i) & 1 (gdb) call debug_generic_expr (op1) 0 Breakpoint 6, fold_unary_loc (loc=0, code=NOP_EXPR, type=0x7ffff5b7e5e8, op0=0x7ffff5b72e70) at /space/rguenther/src/svn/trunk/gcc/fold-const.c:7555 7555 enum tree_code_class kind = TREE_CODE_CLASS (code); (gdb) call debug_generic_expr (op0) (boolean) ((system__unsigned_types__short_unsigned) v->OBJECT >> (integer) i) & 1 (gdb) call debug_generic_expr (type) const boolean Breakpoint 6, fold_unary_loc (loc=0, code=TRUTH_NOT_EXPR, type=0x7ffff5b7e5e8, op0=0x7ffff5b820c8) at /space/rguenther/src/svn/trunk/gcc/fold-const.c:7555 7555 enum tree_code_class kind = TREE_CODE_CLASS (code); ...
fold_truth_not_expr canonicalizes !(A & 1) to (A & 1) == 0 but fold_binary canonicalizes bool == 0 to !bool. A recipie for recursion. fold_truth_not_expr doesn't re-fold its result but its result is fold-converted to bool through which we then end up in that latent cycle.
The old code did not re-fold in /* If we have (type) (a CMP b) and type is an integral type, return new expression involving the new type. */ if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type)) return fold_build2_loc (loc, TREE_CODE (op0), type, TREE_OPERAND (op0, 0), TREE_OPERAND (op0, 1)); for BOOLEAN_TYPE. It could be argued that re-folding is never necessary here because the comparison does not depend on the type of the boolean result it produces. So I'll disable re-folding here.
Author: rguenth Date: Fri May 27 13:13:28 2011 New Revision: 174330 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=174330 Log: 2011-05-27 Richard Guenther <rguenther@suse.de> PR middle-end/49189 * fold-const.c (fold_unary_loc): Do not re-fold folding conversions of comparisons. * gnat.dg/bit_packed_array5.adb: New testcase. * gnat.dg/bit_packed_array5.ads: Likewise. Added: trunk/gcc/testsuite/gnat.dg/bit_packed_array5.adb trunk/gcc/testsuite/gnat.dg/bit_packed_array5.ads Modified: trunk/gcc/ChangeLog trunk/gcc/fold-const.c trunk/gcc/testsuite/ChangeLog
Fixed.
Author: wschmidt Date: Fri May 27 13:29:57 2011 New Revision: 174331 URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=174331 Log: Index: gcc/ChangeLog =================================================================== --- gcc/ChangeLog (revision 174330) +++ gcc/ChangeLog (working copy) @@ -1,3 +1,9 @@ +2011-05-27 Bill Schmidt <wschmidt@linux.vnet.ibm.com> + + PR tree-optimization/49170 + * tree-ssa-math-opts.c (execute_cse_sincos): Add checks for + sincos or cexp. + 2011-05-27 Richard Guenther <rguenther@suse.de> PR middle-end/49189 Index: gcc/tree-ssa-math-opts.c =================================================================== --- gcc/tree-ssa-math-opts.c (revision 174330) +++ gcc/tree-ssa-math-opts.c (working copy) @@ -1093,6 +1093,10 @@ execute_cse_sincos (void) CASE_FLT_FN (BUILT_IN_COS): CASE_FLT_FN (BUILT_IN_SIN): CASE_FLT_FN (BUILT_IN_CEXPI): + /* Make sure we have either sincos or cexp. */ + if (!TARGET_HAS_SINCOS && !TARGET_C99_FUNCTIONS) + break; + arg = gimple_call_arg (stmt, 0); if (TREE_CODE (arg) == SSA_NAME) cfg_changed |= execute_cse_sincos_1 (arg); Modified: trunk/gcc/ChangeLog trunk/gcc/tree-ssa-math-opts.c