compiler, runtime: Fix complex division of NaN / 0.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@203331 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 57 insertions, 1 deletions

diff --git a/libgo/Makefile.am b/libgo/Makefile.am
index c81c66cb07f..957f23ced9f 100644
--- a/libgo/Makefile.am
+++ b/libgo/Makefile.am
@@ -424,6 +424,7 @@ runtime_files = \
 	runtime/go-caller.c \
 	runtime/go-callers.c \
 	runtime/go-can-convert-interface.c \
+	runtime/go-cdiv.c \
 	runtime/go-cgo.c \
 	runtime/go-check-interface.c \
 	runtime/go-construct-map.c \
diff --git a/libgo/Makefile.in b/libgo/Makefile.in
index 9e31e8ca28e..706a72e1d82 100644
--- a/libgo/Makefile.in
+++ b/libgo/Makefile.in
@@ -195,7 +195,7 @@ libgo_la_DEPENDENCIES = $(am__DEPENDENCIES_2) \
 @LIBGO_IS_LINUX_TRUE@am__objects_5 = getncpu-linux.lo
 am__objects_6 = go-append.lo go-assert.lo go-assert-interface.lo \
 	go-byte-array-to-string.lo go-breakpoint.lo go-caller.lo \
-	go-callers.lo go-can-convert-interface.lo go-cgo.lo \
+	go-callers.lo go-can-convert-interface.lo go-cdiv.lo go-cgo.lo \
 	go-check-interface.lo go-construct-map.lo \
 	go-convert-interface.lo go-copy.lo go-defer.lo \
 	go-deferred-recover.lo go-eface-compare.lo \
@@ -757,6 +757,7 @@ runtime_files = \
 	runtime/go-caller.c \
 	runtime/go-callers.c \
 	runtime/go-can-convert-interface.c \
+	runtime/go-cdiv.c \
 	runtime/go-cgo.c \
 	runtime/go-check-interface.c \
 	runtime/go-construct-map.c \
@@ -2368,6 +2369,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-caller.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-callers.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-can-convert-interface.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-cdiv.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-cgo.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-check-interface.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/go-construct-map.Plo@am__quote@
@@ -2554,6 +2556,13 @@ go-can-convert-interface.lo: runtime/go-can-convert-interface.c
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(LIBTOOL)  --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o go-can-convert-interface.lo `test -f 'runtime/go-can-convert-interface.c' || echo '$(srcdir)/'`runtime/go-can-convert-interface.c
 
+go-cdiv.lo: runtime/go-cdiv.c
+@am__fastdepCC_TRUE@	$(LIBTOOL)  --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT go-cdiv.lo -MD -MP -MF $(DEPDIR)/go-cdiv.Tpo -c -o go-cdiv.lo `test -f 'runtime/go-cdiv.c' || echo '$(srcdir)/'`runtime/go-cdiv.c
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/go-cdiv.Tpo $(DEPDIR)/go-cdiv.Plo
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='runtime/go-cdiv.c' object='go-cdiv.lo' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(LIBTOOL)  --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o go-cdiv.lo `test -f 'runtime/go-cdiv.c' || echo '$(srcdir)/'`runtime/go-cdiv.c
+
 go-cgo.lo: runtime/go-cgo.c
 @am__fastdepCC_TRUE@	$(LIBTOOL)  --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT go-cgo.lo -MD -MP -MF $(DEPDIR)/go-cgo.Tpo -c -o go-cgo.lo `test -f 'runtime/go-cgo.c' || echo '$(srcdir)/'`runtime/go-cgo.c
 @am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/go-cgo.Tpo $(DEPDIR)/go-cgo.Plo
diff --git a/libgo/runtime/go-cdiv.c b/libgo/runtime/go-cdiv.c
new file mode 100644
index 00000000000..0a81e458c84
--- /dev/null
+++ b/libgo/runtime/go-cdiv.c
@@ -0,0 +1,46 @@
+/* go-cdiv.c -- complex division routines
+
+   Copyright 2013 The Go Authors. All rights reserved.
+   Use of this source code is governed by a BSD-style
+   license that can be found in the LICENSE file.  */
+
+/* Calls to these functions are generated by the Go frontend for
+   division of complex64 or complex128.  We use these because Go's
+   complex division expects slightly different results from the GCC
+   default.  When dividing NaN+1.0i / 0+0i, Go expects NaN+NaNi but
+   GCC generates NaN+Infi.  NaN+Infi seems wrong seems the rules of
+   C99 Annex G specify that if either side of a complex number is Inf,
+   the the whole number is Inf, but an operation involving NaN ought
+   to result in NaN, not Inf.  */
+
+__complex float
+__go_complex64_div (__complex float a, __complex float b)
+{
+  if (__builtin_expect (b == 0+0i, 0))
+    {
+      if (!__builtin_isinff (__real__ a)
+	  && !__builtin_isinff (__imag__ a)
+	  && (__builtin_isnanf (__real__ a) || __builtin_isnanf (__imag__ a)))
+	{
+	  /* Pass "1" to nanf to match math/bits.go.  */
+	  return __builtin_nanf("1") + __builtin_nanf("1")*1i;
+	}
+    }
+  return a / b;
+}
+
+__complex double
+__go_complex128_div (__complex double a, __complex double b)
+{
+  if (__builtin_expect (b == 0+0i, 0))
+    {
+      if (!__builtin_isinf (__real__ a)
+	  && !__builtin_isinf (__imag__ a)
+	  && (__builtin_isnan (__real__ a) || __builtin_isnan (__imag__ a)))
+	{
+	  /* Pass "1" to nan to match math/bits.go.  */
+	  return __builtin_nan("1") + __builtin_nan("1")*1i;
+	}
+    }
+  return a / b;
+}