From 08884e66575e07544cf5bba20d19e07d62b67a52 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 27 Nov 2001 00:02:21 -0800 Subject: [PATCH] New test. From-SVN: r47370 --- .../gcc.c-torture/execute/20011126-2.c | 43 +++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 gcc/testsuite/gcc.c-torture/execute/20011126-2.c diff --git a/gcc/testsuite/gcc.c-torture/execute/20011126-2.c b/gcc/testsuite/gcc.c-torture/execute/20011126-2.c new file mode 100644 index 00000000000..f6625058afb --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/20011126-2.c @@ -0,0 +1,43 @@ +/* Problem originally visible on ia64. + + There is a partial redundancy of "in + 1" that makes GCSE want to + transform the final while loop to + + p = in + 1; + tmp = p; + ... + goto start; + top: + tmp = tmp + 1; + start: + in = tmp; + if (in < p) goto top; + + We miscalculate the number of loop iterations as (p - tmp) = 0 + instead of (p - in) = 1, which results in overflow in the doloop + optimization. */ + +static const char * +test (const char *in, char *out) +{ + while (1) + { + if (*in == 'a') + { + const char *p = in + 1; + while (*p == 'x') + ++p; + if (*p == 'b') + return p; + while (in < p) + *out++ = *in++; + } + } +} + +int main () +{ + char out[4]; + test ("aab", out); + return 0; +} -- 2.30.2