This patch fixes PR target/77993, which is a bug preventing bootstrapping on
32-bit PowerPC Linux targets.
The issue is that some of the insns that support IFmode (IBM extended double
mode when long double is IEEE 128-bit floating point in the future) did not
check for -msoft-float, and disable IFmode, while others did get disabled. On
64-bit Linux target systems, the soft-float multilib is no longer build, but on
32-bit Linux target systems, it is built.
The fix is to add checks for hardware floating point in the 3 macros used by
IFmode instructions.
I built this on a little endian Power8 system (64-bit only), big endian Power8
system (64-bit only), and a big endian Power7 system (32-bit and 64-bit).
There were no regressions in the test. In addition, Eric Botcazou, who
reported the bug, says that he can now bootstrap his compiler. Is this patch
ok to install?
2016-11-03 Michael Meissner <meiss...@linux.vnet.ibm.com>
PR target/77993
* config/rs6000/rs6000.h (FLOAT128_IBM_P): Do not allow IFmode or
ICmode unless we have standard PowerPC floating point.
* config/rs6000/rs6000.md (FP iterator): Likewise.
(FMOVE128 iterator): Likewise.
--
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meiss...@linux.vnet.ibm.com, phone: +1 (978) 899-4797
Index: gcc/config/rs6000/rs6000.h
===================================================================
--- gcc/config/rs6000/rs6000.h (revision 241715)
+++ gcc/config/rs6000/rs6000.h (working copy)
@@ -442,14 +442,15 @@
point. KFmode was added as a way to represent IEEE 128-bit floating point,
even if the default for long double is the IBM long double format.
Similarly IFmode is the IBM long double format even if the default is IEEE
- 128-bit. */
+ 128-bit. Don't allow IFmode if -msoft-float. */
#define FLOAT128_IEEE_P(MODE) \
((TARGET_IEEEQUAD && ((MODE) == TFmode || (MODE) == TCmode)) \
|| ((MODE) == KFmode) || ((MODE) == KCmode))
#define FLOAT128_IBM_P(MODE) \
((!TARGET_IEEEQUAD && ((MODE) == TFmode || (MODE) == TCmode))
\
- || ((MODE) == IFmode) || ((MODE) == ICmode))
+ || (TARGET_HARD_FLOAT && TARGET_FPRS
\
+ && ((MODE) == IFmode || (MODE) == ICmode)))
/* Helper macros to say whether a 128-bit floating point type can go in a
single vector register, or whether it needs paired scalar values. */
Index: gcc/config/rs6000/rs6000.md
===================================================================
--- gcc/config/rs6000/rs6000.md (revision 241715)
+++ gcc/config/rs6000/rs6000.md (working copy)
@@ -376,7 +376,7 @@
(TF "TARGET_HARD_FLOAT
&& (TARGET_FPRS || TARGET_E500_DOUBLE)
&& TARGET_LONG_DOUBLE_128")
- (IF "TARGET_LONG_DOUBLE_128")
+ (IF "TARGET_HARD_FLOAT && TARGET_FPRS && TARGET_LONG_DOUBLE_128")
(KF "TARGET_FLOAT128_TYPE")
(DD "TARGET_DFP")
(TD "TARGET_DFP")])
@@ -398,7 +398,7 @@
(define_mode_iterator FMOVE64 [DF DD])
(define_mode_iterator FMOVE64X [DI DF DD])
(define_mode_iterator FMOVE128 [(TF "TARGET_LONG_DOUBLE_128")
- (IF "TARGET_LONG_DOUBLE_128")
+ (IF "FLOAT128_IBM_P (IFmode)")
(TD "TARGET_HARD_FLOAT && TARGET_FPRS")])
(define_mode_iterator FMOVE128_FPR [(TF "FLOAT128_2REG_P (TFmode)")
