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| author | Jakub Jelinek <jakub@redhat.com> | 2018-02-07 09:29:58 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2018-02-07 09:29:58 +0100 |
| commit | 40ff1a2d1dd5ab23649e2df91a11534f3e654ace (patch) | |
| tree | 4fc1f3a5020d94acba63a9414fcc4d840a1178d1 | |
| parent | 84c71bb8ecc84f6ca5cbc56786b9ba74eb05057e (diff) | |
| download | gcc-40ff1a2d1dd5ab23649e2df91a11534f3e654ace.zip gcc-40ff1a2d1dd5ab23649e2df91a11534f3e654ace.tar.gz gcc-40ff1a2d1dd5ab23649e2df91a11534f3e654ace.tar.bz2 | |
re PR tree-optimization/84235 (Miscompilation of floating point code by dom2)
PR tree-optimization/84235
* tree-ssa-scopedtables.c
(avail_exprs_stack::simplify_binary_operation): Fir MINUS_EXPR, punt
if the subtraction is performed in floating point type where NaNs are
honored. For *DIV_EXPR, punt for ALL_FRACT_MODE_Ps where we can't
build 1. Formatting fix.
* gcc.c-torture/execute/ieee/pr84235.c: New test.
From-SVN: r257437
| -rw-r--r-- | gcc/ChangeLog | 9 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.c-torture/execute/ieee/pr84235.c | 11 | ||||
| -rw-r--r-- | gcc/tree-ssa-scopedtables.c | 16 |
4 files changed, 38 insertions, 3 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 8edc8cc..088aa47 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2018-02-07 Jakub Jelinek <jakub@redhat.com> + + PR tree-optimization/84235 + * tree-ssa-scopedtables.c + (avail_exprs_stack::simplify_binary_operation): Fir MINUS_EXPR, punt + if the subtraction is performed in floating point type where NaNs are + honored. For *DIV_EXPR, punt for ALL_FRACT_MODE_Ps where we can't + build 1. Formatting fix. + 2018-02-06 Jakub Jelinek <jakub@redhat.com> PR target/84146 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index a32ef37..ac3949a 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-02-07 Jakub Jelinek <jakub@redhat.com> + + PR tree-optimization/84235 + * gcc.c-torture/execute/ieee/pr84235.c: New test. + 2018-02-07 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> PR testsuite/84243 diff --git a/gcc/testsuite/gcc.c-torture/execute/ieee/pr84235.c b/gcc/testsuite/gcc.c-torture/execute/ieee/pr84235.c new file mode 100644 index 0000000..479b2b0 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/ieee/pr84235.c @@ -0,0 +1,11 @@ +/* PR tree-optimization/84235 */ + +int +main () +{ + double d = 1.0 / 0.0; + _Bool b = d == d && (d - d) != (d - d); + if (!b) + __builtin_abort (); + return 0; +} diff --git a/gcc/tree-ssa-scopedtables.c b/gcc/tree-ssa-scopedtables.c index 47cca78..2a40fda 100644 --- a/gcc/tree-ssa-scopedtables.c +++ b/gcc/tree-ssa-scopedtables.c @@ -182,8 +182,15 @@ avail_exprs_stack::simplify_binary_operation (gimple *stmt, case BIT_AND_EXPR: return gimple_assign_rhs1 (stmt); - case BIT_XOR_EXPR: case MINUS_EXPR: + /* This is unsafe for certain floats even in non-IEEE + formats. In IEEE, it is unsafe because it does + wrong for NaNs. */ + if (FLOAT_TYPE_P (result_type) + && HONOR_NANS (result_type)) + break; + /* FALLTHRU */ + case BIT_XOR_EXPR: case TRUNC_MOD_EXPR: case CEIL_MOD_EXPR: case FLOOR_MOD_EXPR: @@ -195,6 +202,9 @@ avail_exprs_stack::simplify_binary_operation (gimple *stmt, case FLOOR_DIV_EXPR: case ROUND_DIV_EXPR: case EXACT_DIV_EXPR: + /* Avoid _Fract types where we can't build 1. */ + if (ALL_FRACT_MODE_P (TYPE_MODE (result_type))) + break; return build_one_cst (result_type); default: @@ -204,8 +214,8 @@ avail_exprs_stack::simplify_binary_operation (gimple *stmt, break; } - default: - break; + default: + break; } } } |