PPC: fix "Warning: FOO uses hard float, BAR uses soft float".

It appears that with recent versions of GCC the explicit "-mhard-float" command line option takes precedence over the ``asm(".gnu_attribute 4, 2");'' in the source file, so this no longer helps to avoid the warnings we get when linking code that uses FP instructions with other code that was built using soft-float. We can remove the ".gnu_attribute" (which appears to carry no other information, at least so far) from the object files, but we also have to make sure we don't pull in the __gcc_qsub() and __gcc_qmul() functions from the standard libgcc, as these would again "infect" our linking. We copy this code from: gcc-4.2.2/gcc/config/rs6000/darwin-ldouble.c This old version was chosen because it was still available under a compatible license (GCC v2+). The file was stripped down to the needed parts, and reformatted so it passes checkpatch with only one warning (do not add new typedefs). Signed-off-by: Wolfgang Denk <wd@denx.de> Cc: Kumar Gala <galak@kernel.crashing.org> Cc: Stefan Roese <sr@denx.de> Cc: Andy Fleming <afleming@gmail.com> Cc: Kim Phillips <kim.phillips@freescale.com> Tested-by: Stefan Roese <sr@denx.de> Tested-by: Anatolij Gustschin <agust@denx.de>

PPC: fix "Warning: FOO uses hard float, BAR uses soft float".
It appears that with recent versions of GCC the explicit "-mhard-float" command line option takes precedence over the ``asm(".gnu_attribute 4, 2");'' in the source file, so this no longer helps to avoid the warnings we get when linking code that uses FP instructions with other code that was built using soft-float. We can remove the ".gnu_attribute" (which appears to carry no other information, at least so far) from the object files, but we also have to make sure we don't pull in the __gcc_qsub() and __gcc_qmul() functions from the standard libgcc, as these would again "infect" our linking. We copy this code from: gcc-4.2.2/gcc/config/rs6000/darwin-ldouble.c This old version was chosen because it was still available under a compatible license (GCC v2+). The file was stripped down to the needed parts, and reformatted so it passes checkpatch with only one warning (do not add new typedefs). Signed-off-by: Wolfgang Denk <wd@denx.de> Cc: Kumar Gala <galak@kernel.crashing.org> Cc: Stefan Roese <sr@denx.de> Cc: Andy Fleming <afleming@gmail.com> Cc: Kim Phillips <kim.phillips@freescale.com> Tested-by: Stefan Roese <sr@denx.de> Tested-by: Anatolij Gustschin <agust@denx.de>
Wolfgang Denk
1 parent af44f4b2a5
Showing 2 changed files with 156 additions and 2 deletions Side-by-side Diff
post/lib_powerpc/fpu/Makefile
post/lib_powerpc/fpu/darwin-ldouble.c
@@ -24,11 +24,24 @@
  
 LIB	= libpost$(ARCH)fpu.o
  
-COBJS-$(CONFIG_HAS_POST)	+= fpu.o 20001122-1.o 20010114-2.o 20010226-1.o 980619-1.o
-COBJS-$(CONFIG_HAS_POST)	+= acc1.o compare-fp-1.o mul-subnormal-single-1.o
+COBJS-$(CONFIG_HAS_POST)	+= 20001122-1.o
+COBJS-$(CONFIG_HAS_POST)	+= 20010114-2.o
+COBJS-$(CONFIG_HAS_POST)	+= 20010226-1.o
+COBJS-$(CONFIG_HAS_POST)	+= 980619-1.o
+COBJS-$(CONFIG_HAS_POST)	+= acc1.o
+COBJS-$(CONFIG_HAS_POST)	+= compare-fp-1.o
+COBJS-$(CONFIG_HAS_POST)	+= fpu.o
+COBJS-$(CONFIG_HAS_POST)	+= mul-subnormal-single-1.o
  
+COBJS-$(CONFIG_HAS_POST)	+= darwin-ldouble.o
+
 include $(TOPDIR)/post/rules.mk
  
 CFLAGS := $(shell echo $(CFLAGS) | sed s/-msoft-float//)
 CFLAGS += -mhard-float -fkeep-inline-functions
+
+$(obj)%.o:	%.c
+	$(CC)  $(ALL_CFLAGS) -o $@.fp $< -c
+	$(OBJCOPY) -R .gnu.attributes $@.fp $@
+	rm -f $@.fp
+/*
+ * Borrowed from GCC 4.2.2 (which still was GPL v2+)
+ */
+/* 128-bit long double support routines for Darwin.
+   Copyright (C) 1993, 2003, 2004, 2005, 2006, 2007
+   Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING.  If not, write to the Free
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA.  */
+
+/*
+ * Implementations of floating-point long double basic arithmetic
+ * functions called by the IBM C compiler when generating code for
+ * PowerPC platforms.  In particular, the following functions are
+ * implemented: __gcc_qadd, __gcc_qsub, __gcc_qmul, and __gcc_qdiv.
+ * Double-double algorithms are based on the paper "Doubled-Precision
+ * IEEE Standard 754 Floating-Point Arithmetic" by W. Kahan, February 26,
+ * 1987.  An alternative published reference is "Software for
+ * Doubled-Precision Floating-Point Computations", by Seppo Linnainmaa,
+ * ACM TOMS vol 7 no 3, September 1981, pages 272-283.
+ */
+
+/*
+ * Each long double is made up of two IEEE doubles.  The value of the
+ * long double is the sum of the values of the two parts.  The most
+ * significant part is required to be the value of the long double
+ * rounded to the nearest double, as specified by IEEE.  For Inf
+ * values, the least significant part is required to be one of +0.0 or
+ * -0.0.  No other requirements are made; so, for example, 1.0 may be
+ * represented as (1.0, +0.0) or (1.0, -0.0), and the low part of a
+ * NaN is don't-care.
+ *
+ * This code currently assumes big-endian.
+ */
+
+#define fabs(x) __builtin_fabs(x)
+#define isless(x, y) __builtin_isless(x, y)
+#define inf() __builtin_inf()
+#define unlikely(x) __builtin_expect((x), 0)
+#define nonfinite(a) unlikely(!isless(fabs(a), inf()))
+
+typedef union {
+	long double ldval;
+	double dval[2];
+} longDblUnion;
+
+/* Add two 'long double' values and return the result.	*/
+long double __gcc_qadd(double a, double aa, double c, double cc)
+{
+	longDblUnion x;
+	double z, q, zz, xh;
+
+	z = a + c;
+
+	if (nonfinite(z)) {
+		z = cc + aa + c + a;
+		if (nonfinite(z))
+			return z;
+		x.dval[0] = z;	/* Will always be DBL_MAX.  */
+		zz = aa + cc;
+		if (fabs(a) > fabs(c))
+			x.dval[1] = a - z + c + zz;
+		else
+			x.dval[1] = c - z + a + zz;
+	} else {
+		q = a - z;
+		zz = q + c + (a - (q + z)) + aa + cc;
+
+		/* Keep -0 result.  */
+		if (zz == 0.0)
+			return z;
+
+		xh = z + zz;
+		if (nonfinite(xh))
+			return xh;
+
+		x.dval[0] = xh;
+		x.dval[1] = z - xh + zz;
+	}
+	return x.ldval;
+}
+
+long double __gcc_qsub(double a, double b, double c, double d)
+{
+	return __gcc_qadd(a, b, -c, -d);
+}
+
+long double __gcc_qmul(double a, double b, double c, double d)
+{
+	longDblUnion z;
+	double t, tau, u, v, w;
+
+	t = a * c;		/* Highest order double term.  */
+
+	if (unlikely(t == 0)	/* Preserve -0.  */
+	    || nonfinite(t))
+		return t;
+
+	/* Sum terms of two highest orders. */
+
+	/* Use fused multiply-add to get low part of a * c.  */
+#ifndef __NO_FPRS__
+	asm("fmsub %0,%1,%2,%3" : "=f"(tau) : "f"(a), "f"(c), "f"(t));
+#else
+	tau = fmsub(a, c, t);
+#endif
+	v = a * d;
+	w = b * c;
+	tau += v + w;		/* Add in other second-order terms.  */
+	u = t + tau;
+
+	/* Construct long double result.  */
+	if (nonfinite(u))
+		return u;
+	z.dval[0] = u;
+	z.dval[1] = (t - u) + tau;
+	return z.ldval;
+}
...	...	@@ -24,11 +24,24 @@
24	24
25	25	LIB = libpost$(ARCH)fpu.o
26	26
27		-COBJS-$(CONFIG_HAS_POST) += fpu.o 20001122-1.o 20010114-2.o 20010226-1.o 980619-1.o
28		-COBJS-$(CONFIG_HAS_POST) += acc1.o compare-fp-1.o mul-subnormal-single-1.o
	27	+COBJS-$(CONFIG_HAS_POST) += 20001122-1.o
	28	+COBJS-$(CONFIG_HAS_POST) += 20010114-2.o
	29	+COBJS-$(CONFIG_HAS_POST) += 20010226-1.o
	30	+COBJS-$(CONFIG_HAS_POST) += 980619-1.o
	31	+COBJS-$(CONFIG_HAS_POST) += acc1.o
	32	+COBJS-$(CONFIG_HAS_POST) += compare-fp-1.o
	33	+COBJS-$(CONFIG_HAS_POST) += fpu.o
	34	+COBJS-$(CONFIG_HAS_POST) += mul-subnormal-single-1.o
29	35
	36	+COBJS-$(CONFIG_HAS_POST) += darwin-ldouble.o
	37	+
30	38	include $(TOPDIR)/post/rules.mk
31	39
32	40	CFLAGS := $(shell echo $(CFLAGS) \| sed s/-msoft-float//)
33	41	CFLAGS += -mhard-float -fkeep-inline-functions
	42	+
	43	+$(obj)%.o: %.c
	44	+ $(CC) $(ALL_CFLAGS) -o $@.fp $< -c
	45	+ $(OBJCOPY) -R .gnu.attributes $@.fp $@
	46	+ rm -f $@.fp
	1	+/*
	2	+ * Borrowed from GCC 4.2.2 (which still was GPL v2+)
	3	+ */
	4	+/* 128-bit long double support routines for Darwin.
	5	+ Copyright (C) 1993, 2003, 2004, 2005, 2006, 2007
	6	+ Free Software Foundation, Inc.
	7	+
	8	+This file is part of GCC.
	9	+
	10	+GCC is free software; you can redistribute it and/or modify it under
	11	+the terms of the GNU General Public License as published by the Free
	12	+Software Foundation; either version 2, or (at your option) any later
	13	+version.
	14	+
	15	+In addition to the permissions in the GNU General Public License, the
	16	+Free Software Foundation gives you unlimited permission to link the
	17	+compiled version of this file into combinations with other programs,
	18	+and to distribute those combinations without any restriction coming
	19	+from the use of this file. (The General Public License restrictions
	20	+do apply in other respects; for example, they cover modification of
	21	+the file, and distribution when not linked into a combine
	22	+executable.)
	23	+
	24	+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
	25	+WARRANTY; without even the implied warranty of MERCHANTABILITY or
	26	+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	27	+for more details.
	28	+
	29	+You should have received a copy of the GNU General Public License
	30	+along with GCC; see the file COPYING. If not, write to the Free
	31	+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
	32	+02110-1301, USA. */
	33	+
	34	+/*
	35	+ * Implementations of floating-point long double basic arithmetic
	36	+ * functions called by the IBM C compiler when generating code for
	37	+ * PowerPC platforms. In particular, the following functions are
	38	+ * implemented: __gcc_qadd, __gcc_qsub, __gcc_qmul, and __gcc_qdiv.
	39	+ * Double-double algorithms are based on the paper "Doubled-Precision
	40	+ * IEEE Standard 754 Floating-Point Arithmetic" by W. Kahan, February 26,
	41	+ * 1987. An alternative published reference is "Software for
	42	+ * Doubled-Precision Floating-Point Computations", by Seppo Linnainmaa,
	43	+ * ACM TOMS vol 7 no 3, September 1981, pages 272-283.
	44	+ */
	45	+
	46	+/*
	47	+ * Each long double is made up of two IEEE doubles. The value of the
	48	+ * long double is the sum of the values of the two parts. The most
	49	+ * significant part is required to be the value of the long double
	50	+ * rounded to the nearest double, as specified by IEEE. For Inf
	51	+ * values, the least significant part is required to be one of +0.0 or
	52	+ * -0.0. No other requirements are made; so, for example, 1.0 may be
	53	+ * represented as (1.0, +0.0) or (1.0, -0.0), and the low part of a
	54	+ * NaN is don't-care.
	55	+ *
	56	+ * This code currently assumes big-endian.
	57	+ */
	58	+
	59	+#define fabs(x) __builtin_fabs(x)
	60	+#define isless(x, y) __builtin_isless(x, y)
	61	+#define inf() __builtin_inf()
	62	+#define unlikely(x) __builtin_expect((x), 0)
	63	+#define nonfinite(a) unlikely(!isless(fabs(a), inf()))
	64	+
	65	+typedef union {
	66	+ long double ldval;
	67	+ double dval[2];
	68	+} longDblUnion;
	69	+
	70	+/* Add two 'long double' values and return the result. */
	71	+long double __gcc_qadd(double a, double aa, double c, double cc)
	72	+{
	73	+ longDblUnion x;
	74	+ double z, q, zz, xh;
	75	+
	76	+ z = a + c;
	77	+
	78	+ if (nonfinite(z)) {
	79	+ z = cc + aa + c + a;
	80	+ if (nonfinite(z))
	81	+ return z;
	82	+ x.dval[0] = z; /* Will always be DBL_MAX. */
	83	+ zz = aa + cc;
	84	+ if (fabs(a) > fabs(c))
	85	+ x.dval[1] = a - z + c + zz;
	86	+ else
	87	+ x.dval[1] = c - z + a + zz;
	88	+ } else {
	89	+ q = a - z;
	90	+ zz = q + c + (a - (q + z)) + aa + cc;
	91	+
	92	+ /* Keep -0 result. */
	93	+ if (zz == 0.0)
	94	+ return z;
	95	+
	96	+ xh = z + zz;
	97	+ if (nonfinite(xh))
	98	+ return xh;
	99	+
	100	+ x.dval[0] = xh;
	101	+ x.dval[1] = z - xh + zz;
	102	+ }
	103	+ return x.ldval;
	104	+}
	105	+
	106	+long double __gcc_qsub(double a, double b, double c, double d)
	107	+{
	108	+ return __gcc_qadd(a, b, -c, -d);
	109	+}
	110	+
	111	+long double __gcc_qmul(double a, double b, double c, double d)
	112	+{
	113	+ longDblUnion z;
	114	+ double t, tau, u, v, w;
	115	+
	116	+ t = a * c; /* Highest order double term. */
	117	+
	118	+ if (unlikely(t == 0) /* Preserve -0. */
	119	+ \|\| nonfinite(t))
	120	+ return t;
	121	+
	122	+ /* Sum terms of two highest orders. */
	123	+
	124	+ /* Use fused multiply-add to get low part of a * c. */
	125	+#ifndef __NO_FPRS__
	126	+ asm("fmsub %0,%1,%2,%3" : "=f"(tau) : "f"(a), "f"(c), "f"(t));
	127	+#else
	128	+ tau = fmsub(a, c, t);
	129	+#endif
	130	+ v = a * d;
	131	+ w = b * c;
	132	+ tau += v + w; /* Add in other second-order terms. */
	133	+ u = t + tau;
	134	+
	135	+ /* Construct long double result. */
	136	+ if (nonfinite(u))
	137	+ return u;
	138	+ z.dval[0] = u;
	139	+ z.dval[1] = (t - u) + tau;
	140	+ return z.ldval;
	141	+}