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denormal patch
- To: gcc-patches at gcc dot gnu dot org
- Subject: denormal patch
- From: Geoff Keating <geoffk at cygnus dot com>
- Date: Mon, 20 Mar 2000 18:10:59 -0800
This fixes a minor problem with denormals and soft-float that my
previous patch missed, and adds a test case (tip: never check
test-case results by eye...).
OK to commit?
--
- Geoffrey Keating <geoffk@cygnus.com>
===File ~/patches/cygnus/egcs-denormal2.patch===============
Index: ChangeLog
===================================================================
RCS file: /cvs/gcc/egcs/gcc/ChangeLog,v
retrieving revision 1.5995
diff -p -u -c -p -r1.5995 ChangeLog
*** ChangeLog 2000/03/20 23:47:38 1.5995
--- ChangeLog 2000/03/21 00:56:25
***************
*** 1,5 ****
--- 1,10 ----
2000-03-20 Geoff Keating <geoffk@cygnus.com>
+ * config/fp-bit.c (pack_d): Correct the case when a denormal
+ is rounded up and stops being denormal.
+
+ 2000-03-20 Geoff Keating <geoffk@cygnus.com>
+
* config/rs6000/rs6000.md (bunordered): New expander.
(bordered): New expander.
(buneq): New expander.
Index: config/fp-bit.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/config/fp-bit.c,v
retrieving revision 1.18
diff -p -u -c -p -r1.18 fp-bit.c
*** fp-bit.c 2000/03/16 17:20:57 1.18
--- fp-bit.c 2000/03/21 00:56:25
*************** pack_d ( fp_number_type * src)
*** 518,527 ****
fraction += GARDROUND;
}
/* Perhaps the rounding means we now need to change the
! exponent. */
! if (fraction >= IMPLICIT_2)
{
- fraction >>= 1;
exp += 1;
}
fraction >>= NGARDS;
--- 518,526 ----
fraction += GARDROUND;
}
/* Perhaps the rounding means we now need to change the
! exponent, because the fraction is no longer denormal. */
! if (fraction >= IMPLICIT_1)
{
exp += 1;
}
fraction >>= NGARDS;
Index: testsuite/gcc.c-torture/ChangeLog
===================================================================
RCS file: /cvs/gcc/egcs/gcc/testsuite/gcc.c-torture/ChangeLog,v
retrieving revision 1.64
diff -p -u -c -p -r1.64 ChangeLog
*** ChangeLog 2000/03/18 03:26:47 1.64
--- ChangeLog 2000/03/21 00:56:27
***************
*** 1,3 ****
--- 1,7 ----
+ 2000-03-20 Geoff Keating <geoffk@cygnus.com>
+
+ * execute/ieee/20000320-1.c: New test for denormals.
+
Fri Mar 10 01:15:19 2000 Hans-Peter Nilsson <hp@bitrange.com>
* execute/divconst-2.c: Rewrite to check for standards-compliant
Index: testsuite/gcc.c-torture/execute/ieee/20000320-1.c
===================================================================
RCS file: 20000320-1.c
diff -N 20000320-1.c
*** /dev/null Tue May 5 13:32:27 1998
--- 20000320-1.c Mon Mar 20 16:56:27 2000
***************
*** 0 ****
--- 1,56 ----
+ typedef unsigned long long ull;
+ typedef unsigned int ul;
+
+ union fl {
+ float f;
+ ul l;
+ } uf;
+ union dl {
+ double d;
+ ull ll;
+ } ud;
+
+ int failed = 0;
+
+ void c(ull d, ul f)
+ {
+ ud.ll = d;
+ uf.f = (float) ud.d;
+ if (uf.l != f)
+ {
+ failed++;
+ printf("0x%08x.%08x => %08x (%.20g, %.10g)\n",
+ (ul) (ud.ll >> 32), (ul) ud.ll, uf.l, ud.d, uf.f);
+ }
+ }
+
+ int main()
+ {
+ c(0x3690000000000000ULL, 0x00000000U);
+ c(0x3690000000000001ULL, 0x00000001U);
+ c(0x369fffffffffffffULL, 0x00000001U);
+ c(0x36A0000000000000ULL, 0x00000001U);
+ c(0x36A7ffffffffffffULL, 0x00000001U);
+ c(0x36A8000000000000ULL, 0x00000002U);
+ c(0x36AfffffffffffffULL, 0x00000002U);
+ c(0x36b0000000000000ULL, 0x00000002U);
+ c(0x36b0000000000001ULL, 0x00000002U);
+
+ c(0x380fffffdfffffffULL, 0x007fffffU);
+ c(0x380fffffe0000000ULL, 0x00800000U);
+ c(0x380fffffe0000001ULL, 0x00800000U);
+ c(0x380fffffffffffffULL, 0x00800000U);
+ c(0x3810000000000000ULL, 0x00800000U);
+ c(0x3810000000000001ULL, 0x00800000U);
+ c(0x3810000010000000ULL, 0x00800000U);
+ c(0x3810000010000001ULL, 0x00800001U);
+ c(0x381000002fffffffULL, 0x00800001U);
+ c(0x3810000030000000ULL, 0x00800002U);
+ c(0x3810000050000000ULL, 0x00800002U);
+ c(0x3810000050000001ULL, 0x00800003U);
+
+ if (failed)
+ abort ();
+ else
+ exit (0);
+ }
============================================================