diff options
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/fold-const.c | 8 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/compare3.c | 59 |
4 files changed, 74 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6932876..23c0eb5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2000-12-18 Kaveh R. Ghazi <ghazi@caip.rutgers.edu> + + * fold-const.c (tree_expr_nonnegative_p): Treat truth values as + non-negative. + Tue Dec 19 00:37:08 2000 J"orn Rennecke <amylaar@redhat.com> * reload.c (push_reload): When using a dying register for the reload diff --git a/gcc/fold-const.c b/gcc/fold-const.c index d8131fa..a0a76b2 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -7299,8 +7299,12 @@ tree_expr_nonnegative_p (t) return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t)); default: - /* We don't know sign of `t', so be safe and return false. */ - return 0; + if (truth_value_p (TREE_CODE (t))) + /* Truth values evaluate to 0 or 1, which is nonnegative. */ + return 1; + else + /* We don't know sign of `t', so be conservative and return false. */ + return 0; } } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index b60cda7..06c54bc 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2000-12-18 Kaveh R. Ghazi <ghazi@caip.rutgers.edu> + + * gcc.dg/compare3.c: New test. + 2000-12-18 Joseph S. Myers <jsm28@cam.ac.uk> * gcc.dg/format-warnll-1.c: New test. diff --git a/gcc/testsuite/gcc.dg/compare3.c b/gcc/testsuite/gcc.dg/compare3.c new file mode 100644 index 0000000..eda3faf --- /dev/null +++ b/gcc/testsuite/gcc.dg/compare3.c @@ -0,0 +1,59 @@ +/* Test for a bogus warning on comparison between signed and unsigned. + This was inspired by code in gcc. */ + +/* { dg-do compile } */ +/* { dg-options "-Wsign-compare" } */ + +int tf = 1; + +void f(int x, unsigned int y) +{ + /* Test comparing conditional expressions containing truth values. + This can occur explicitly, or e.g. when (foo?2:(bar?1:0)) is + optimized into (foo?2:(bar!=0)). */ + x > (tf?64:(tf!=x)); /* { dg-bogus "signed and unsigned" "case 1" } */ + y > (tf?64:(tf!=x)); /* { dg-bogus "signed and unsigned" "case 2" } */ + x > (tf?(tf!=x):64); /* { dg-bogus "signed and unsigned" "case 3" } */ + y > (tf?(tf!=x):64); /* { dg-bogus "signed and unsigned" "case 4" } */ + + x > (tf?64:(tf==x)); /* { dg-bogus "signed and unsigned" "case 5" } */ + y > (tf?64:(tf==x)); /* { dg-bogus "signed and unsigned" "case 6" } */ + x > (tf?(tf==x):64); /* { dg-bogus "signed and unsigned" "case 7" } */ + y > (tf?(tf==x):64); /* { dg-bogus "signed and unsigned" "case 8" } */ + + x > (tf?64:(tf>x)); /* { dg-bogus "signed and unsigned" "case 9" } */ + y > (tf?64:(tf>x)); /* { dg-bogus "signed and unsigned" "case 10" } */ + x > (tf?(tf>x):64); /* { dg-bogus "signed and unsigned" "case 11" } */ + y > (tf?(tf>x):64); /* { dg-bogus "signed and unsigned" "case 12" } */ + + x < (tf?64:(tf<x)); /* { dg-bogus "signed and unsigned" "case 13" } */ + y < (tf?64:(tf<x)); /* { dg-bogus "signed and unsigned" "case 14" } */ + x < (tf?(tf<x):64); /* { dg-bogus "signed and unsigned" "case 15" } */ + y < (tf?(tf<x):64); /* { dg-bogus "signed and unsigned" "case 16" } */ + + x > (tf?64:(tf>=x)); /* { dg-bogus "signed and unsigned" "case 17" } */ + y > (tf?64:(tf>=x)); /* { dg-bogus "signed and unsigned" "case 18" } */ + x > (tf?(tf>=x):64); /* { dg-bogus "signed and unsigned" "case 19" } */ + y > (tf?(tf>=x):64); /* { dg-bogus "signed and unsigned" "case 20" } */ + + x > (tf?64:(tf<=x)); /* { dg-bogus "signed and unsigned" "case 21" } */ + y > (tf?64:(tf<=x)); /* { dg-bogus "signed and unsigned" "case 22" } */ + x > (tf?(tf<=x):64); /* { dg-bogus "signed and unsigned" "case 23" } */ + y > (tf?(tf<=x):64); /* { dg-bogus "signed and unsigned" "case 24" } */ + + x > (tf?64:(tf&&x)); /* { dg-bogus "signed and unsigned" "case 25" } */ + y > (tf?64:(tf&&x)); /* { dg-bogus "signed and unsigned" "case 26" } */ + x > (tf?(tf&&x):64); /* { dg-bogus "signed and unsigned" "case 27" } */ + y > (tf?(tf&&x):64); /* { dg-bogus "signed and unsigned" "case 28" } */ + + x > (tf?64:(tf||x)); /* { dg-bogus "signed and unsigned" "case 29" } */ + y > (tf?64:(tf||x)); /* { dg-bogus "signed and unsigned" "case 30" } */ + x > (tf?(tf||x):64); /* { dg-bogus "signed and unsigned" "case 31" } */ + y > (tf?(tf||x):64); /* { dg-bogus "signed and unsigned" "case 32" } */ + + x > (tf?64:(!tf)); /* { dg-bogus "signed and unsigned" "case 33" } */ + y > (tf?64:(!tf)); /* { dg-bogus "signed and unsigned" "case 34" } */ + x > (tf?(!tf):64); /* { dg-bogus "signed and unsigned" "case 35" } */ + y > (tf?(!tf):64); /* { dg-bogus "signed and unsigned" "case 36" } */ + +} |