| Message ID | 20120813120134.GJ1999@tucnak.redhat.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Aug 13, 2012 at 2:01 PM, Jakub Jelinek <jakub@redhat.com> wrote: > Hi! > > John Regehr discovered a couple of spots in GCC sources that invoke > undefined behavior during bootstrap/regtest, the following patch fixes most > of them. I couldn't reproduce the diagnostic.c failure and would like to > leave the ipa hunk to Honza, I think the probability/frequency code often > might go out of the expected limits and then invoke undefined signed > overflow. > > The double_int_mask change is because e.g. with -E, ptr_mode is VOIDmode and > so double_int_mask is called with 0 precision during compiler > initialization. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Ok. Thanks, Richard. > 2012-08-13 Jakub Jelinek <jakub@redhat.com> > > PR c/53968 > * tree.c (integer_pow2p): Avoid undefined signed overflows. > * simplify-rtx.c (neg_const_int): Likewise. > * expr.c (fixup_args_size_notes): Likewise. > * stor-layout.c (set_min_and_max_values_for_integral_type): Likewise. > * double-int.c (mul_double_wide_with_sign): Likewise. > (double_int_mask): Likewise. > * tree-ssa-loop-ivopts.c (get_address_cost): Likewise. > > --- gcc/tree.c.jj 2012-08-10 15:48:53.000000000 +0200 > +++ gcc/tree.c 2012-08-13 10:25:46.610502929 +0200 > @@ -1849,7 +1849,7 @@ int > integer_pow2p (const_tree expr) > { > int prec; > - HOST_WIDE_INT high, low; > + unsigned HOST_WIDE_INT high, low; > > STRIP_NOPS (expr); > > --- gcc/simplify-rtx.c.jj 2012-08-10 15:49:20.000000000 +0200 > +++ gcc/simplify-rtx.c 2012-08-13 09:51:43.628508537 +0200 > @@ -66,7 +66,7 @@ static rtx simplify_binary_operation_1 ( > static rtx > neg_const_int (enum machine_mode mode, const_rtx i) > { > - return gen_int_mode (- INTVAL (i), mode); > + return gen_int_mode (-(unsigned HOST_WIDE_INT) INTVAL (i), mode); > } > > /* Test whether expression, X, is an immediate constant that represents > --- gcc/expr.c.jj 2012-08-10 15:49:07.000000000 +0200 > +++ gcc/expr.c 2012-08-13 10:40:01.182501639 +0200 > @@ -3828,7 +3828,7 @@ fixup_args_size_notes (rtx prev, rtx las > > add_reg_note (insn, REG_ARGS_SIZE, GEN_INT (args_size)); > #ifdef STACK_GROWS_DOWNWARD > - this_delta = -this_delta; > + this_delta = -(unsigned HOST_WIDE_INT) this_delta; > #endif > args_size -= this_delta; > } > --- gcc/stor-layout.c.jj 2012-08-10 15:49:20.000000000 +0200 > +++ gcc/stor-layout.c 2012-08-13 10:14:14.388505253 +0200 > @@ -2568,10 +2568,14 @@ set_min_and_max_values_for_integral_type > = build_int_cst_wide (type, > (precision - HOST_BITS_PER_WIDE_INT > 0 > ? -1 > - : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1), > + : (HOST_WIDE_INT) > + (((unsigned HOST_WIDE_INT) 1 > + << (precision - 1)) - 1)), > (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 > - ? (((HOST_WIDE_INT) 1 > - << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1 > + ? (HOST_WIDE_INT) > + ((((unsigned HOST_WIDE_INT) 1 > + << (precision - HOST_BITS_PER_WIDE_INT > + - 1))) - 1) > : 0)); > } > > --- gcc/double-int.c.jj 2012-08-10 15:49:07.000000000 +0200 > +++ gcc/double-int.c 2012-08-13 11:24:17.816495757 +0200 > @@ -170,7 +170,7 @@ mul_double_wide_with_sign (unsigned HOST > { > k = i + j; > /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ > - carry += arg1[i] * arg2[j]; > + carry += (unsigned HOST_WIDE_INT) arg1[i] * arg2[j]; > /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ > carry += prod[k]; > prod[k] = LOWPART (carry); > @@ -625,7 +625,7 @@ double_int_mask (unsigned prec) > else > { > mask.high = 0; > - mask.low = ((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1; > + mask.low = prec ? ((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1 : 0; > } > > return mask; > --- gcc/tree-ssa-loop-ivopts.c.jj 2012-08-10 15:49:07.000000000 +0200 > +++ gcc/tree-ssa-loop-ivopts.c 2012-08-13 10:17:51.227504425 +0200 > @@ -3173,7 +3173,7 @@ get_address_cost (bool symbol_present, b > > for (i = width; i >= 0; i--) > { > - off = -((HOST_WIDE_INT) 1 << i); > + off = -((unsigned HOST_WIDE_INT) 1 << i); > XEXP (addr, 1) = gen_int_mode (off, address_mode); > if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > @@ -3182,7 +3182,7 @@ get_address_cost (bool symbol_present, b > > for (i = width; i >= 0; i--) > { > - off = ((HOST_WIDE_INT) 1 << i) - 1; > + off = ((unsigned HOST_WIDE_INT) 1 << i) - 1; > XEXP (addr, 1) = gen_int_mode (off, address_mode); > if (memory_address_addr_space_p (mem_mode, addr, as)) > break; > > Jakub
Jakub Jelinek <jakub@redhat.com> writes: > --- gcc/simplify-rtx.c.jj 2012-08-10 15:49:20.000000000 +0200 > +++ gcc/simplify-rtx.c 2012-08-13 09:51:43.628508537 +0200 > @@ -66,7 +66,7 @@ static rtx simplify_binary_operation_1 ( > static rtx > neg_const_int (enum machine_mode mode, const_rtx i) > { > - return gen_int_mode (- INTVAL (i), mode); > + return gen_int_mode (-(unsigned HOST_WIDE_INT) INTVAL (i), mode); Really minor, but UINTVAL would be nicer. Richard
--- gcc/tree.c.jj 2012-08-10 15:48:53.000000000 +0200 +++ gcc/tree.c 2012-08-13 10:25:46.610502929 +0200 @@ -1849,7 +1849,7 @@ int integer_pow2p (const_tree expr) { int prec; - HOST_WIDE_INT high, low; + unsigned HOST_WIDE_INT high, low; STRIP_NOPS (expr); --- gcc/simplify-rtx.c.jj 2012-08-10 15:49:20.000000000 +0200 +++ gcc/simplify-rtx.c 2012-08-13 09:51:43.628508537 +0200 @@ -66,7 +66,7 @@ static rtx simplify_binary_operation_1 ( static rtx neg_const_int (enum machine_mode mode, const_rtx i) { - return gen_int_mode (- INTVAL (i), mode); + return gen_int_mode (-(unsigned HOST_WIDE_INT) INTVAL (i), mode); } /* Test whether expression, X, is an immediate constant that represents --- gcc/expr.c.jj 2012-08-10 15:49:07.000000000 +0200 +++ gcc/expr.c 2012-08-13 10:40:01.182501639 +0200 @@ -3828,7 +3828,7 @@ fixup_args_size_notes (rtx prev, rtx las add_reg_note (insn, REG_ARGS_SIZE, GEN_INT (args_size)); #ifdef STACK_GROWS_DOWNWARD - this_delta = -this_delta; + this_delta = -(unsigned HOST_WIDE_INT) this_delta; #endif args_size -= this_delta; } --- gcc/stor-layout.c.jj 2012-08-10 15:49:20.000000000 +0200 +++ gcc/stor-layout.c 2012-08-13 10:14:14.388505253 +0200 @@ -2568,10 +2568,14 @@ set_min_and_max_values_for_integral_type = build_int_cst_wide (type, (precision - HOST_BITS_PER_WIDE_INT > 0 ? -1 - : ((HOST_WIDE_INT) 1 << (precision - 1)) - 1), + : (HOST_WIDE_INT) + (((unsigned HOST_WIDE_INT) 1 + << (precision - 1)) - 1)), (precision - HOST_BITS_PER_WIDE_INT - 1 > 0 - ? (((HOST_WIDE_INT) 1 - << (precision - HOST_BITS_PER_WIDE_INT - 1))) - 1 + ? (HOST_WIDE_INT) + ((((unsigned HOST_WIDE_INT) 1 + << (precision - HOST_BITS_PER_WIDE_INT + - 1))) - 1) : 0)); } --- gcc/double-int.c.jj 2012-08-10 15:49:07.000000000 +0200 +++ gcc/double-int.c 2012-08-13 11:24:17.816495757 +0200 @@ -170,7 +170,7 @@ mul_double_wide_with_sign (unsigned HOST { k = i + j; /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */ - carry += arg1[i] * arg2[j]; + carry += (unsigned HOST_WIDE_INT) arg1[i] * arg2[j]; /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */ carry += prod[k]; prod[k] = LOWPART (carry); @@ -625,7 +625,7 @@ double_int_mask (unsigned prec) else { mask.high = 0; - mask.low = ((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1; + mask.low = prec ? ((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1 : 0; } return mask; --- gcc/tree-ssa-loop-ivopts.c.jj 2012-08-10 15:49:07.000000000 +0200 +++ gcc/tree-ssa-loop-ivopts.c 2012-08-13 10:17:51.227504425 +0200 @@ -3173,7 +3173,7 @@ get_address_cost (bool symbol_present, b for (i = width; i >= 0; i--) { - off = -((HOST_WIDE_INT) 1 << i); + off = -((unsigned HOST_WIDE_INT) 1 << i); XEXP (addr, 1) = gen_int_mode (off, address_mode); if (memory_address_addr_space_p (mem_mode, addr, as)) break; @@ -3182,7 +3182,7 @@ get_address_cost (bool symbol_present, b for (i = width; i >= 0; i--) { - off = ((HOST_WIDE_INT) 1 << i) - 1; + off = ((unsigned HOST_WIDE_INT) 1 << i) - 1; XEXP (addr, 1) = gen_int_mode (off, address_mode); if (memory_address_addr_space_p (mem_mode, addr, as)) break;