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| author | Jakub Jelinek <jakub@redhat.com> | 2007-12-18 01:13:29 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2007-12-18 01:13:29 +0100 |
| commit | dc7c279e97760bba05fa4d637d5652f8559eab3a (patch) | |
| tree | 8b72d93c5aed08c343fa4fbc730ba4c7f0b0b5bc /gcc | |
| parent | 44f37984f4e87411999989e2c3ff715a4860d9c3 (diff) | |
| download | gcc-dc7c279e97760bba05fa4d637d5652f8559eab3a.zip gcc-dc7c279e97760bba05fa4d637d5652f8559eab3a.tar.gz gcc-dc7c279e97760bba05fa4d637d5652f8559eab3a.tar.bz2 | |
re PR rtl-optimization/34490 (r128833 causes miscompilation of glibc clock_gettime.c)
PR rtl-optimization/34490
* simplify-rtx.c (simplify_const_relational_operation): If !sign,
don't reduce mmin/mmax using num_sign_bit_copies.
* gcc.c-torture/execute/20071216-1.c: New test.
From-SVN: r131023
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/simplify-rtx.c | 16 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.c-torture/execute/20071216-1.c | 38 |
4 files changed, 58 insertions, 7 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c71729d..c3595a4 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2007-12-18 Jakub Jelinek <jakub@redhat.com> + + PR rtl-optimization/34490 + * simplify-rtx.c (simplify_const_relational_operation): If !sign, + don't reduce mmin/mmax using num_sign_bit_copies. + 2007-12-17 Kaveh R. Ghazi <ghazi@caip.rutgers.edu> * doc/install.texi: Change recommended MPFR from 2.2.1 > 2.3.0. diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index 0371339..fd14e40 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -4233,15 +4233,17 @@ simplify_const_relational_operation (enum rtx_code code, else { rtx mmin_rtx, mmax_rtx; - unsigned int sign_copies = num_sign_bit_copies (trueop0, mode); get_mode_bounds (mode, sign, mode, &mmin_rtx, &mmax_rtx); - /* Since unsigned mmin will never be interpreted as negative, use - INTVAL (and an arithmetic right shift). */ - mmin = INTVAL (mmin_rtx) >> (sign_copies - 1); - /* Since signed mmax will always be positive, use UINTVAL (and - a logical right shift). */ - mmax = UINTVAL (mmax_rtx) >> (sign_copies - 1); + mmin = INTVAL (mmin_rtx); + mmax = INTVAL (mmax_rtx); + if (sign) + { + unsigned int sign_copies = num_sign_bit_copies (trueop0, mode); + + mmin >>= (sign_copies - 1); + mmax >>= (sign_copies - 1); + } } switch (code) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 1650e37..d42c334 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2007-12-18 Jakub Jelinek <jakub@redhat.com> + + PR rtl-optimization/34490 + * gcc.c-torture/execute/20071216-1.c: New test. + 2007-12-17 Kaveh R. Ghazi <ghazi@caip.rutgers.edu> * gcc.dg/torture/builtin-math-4.c: Remove XFAIL. diff --git a/gcc/testsuite/gcc.c-torture/execute/20071216-1.c b/gcc/testsuite/gcc.c-torture/execute/20071216-1.c new file mode 100644 index 0000000..a337b77 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/20071216-1.c @@ -0,0 +1,38 @@ +/* PR rtl-optimization/34490 */ + +extern void abort (void); + +static int x; + +int +__attribute__((noinline)) +bar (void) +{ + return x; +} + +int +foo (void) +{ + long int b = bar (); + if ((unsigned long) b < -4095L) + return b; + if (-b != 38) + b = -2; + return b + 1; +} + +int +main (void) +{ + x = 26; + if (foo () != 26) + abort (); + x = -39; + if (foo () != -1) + abort (); + x = -38; + if (foo () != -37) + abort (); + return 0; +} |