| Message ID | 1665825.0OqtZUyZYm@polaris |
|---|---|
| State | New |
| Headers | show |
Hi Eric, > this isn't really valid Ada semantics, but some people enable traps-on-fp- > exceptions in the FPU on Solaris and expect the Ada exception to be caught. > There is a glitch with the x87 and the SPARC FPUs: the SIGFPE is delivered > after the faulting instruction by Solaris, so the unwinder is fooled and > miscomputes the faulting address. > > Fixed thusly, tested on x86/Solaris and SPARC/Solaris, OK for mainline? I've included the patch in my Solaris bootstraps this weekend, and results don't look good: * On Solaris 9/x86 and Solaris 10/x86 (both 32- and 64-bit), I get a new ACATS failure which may or may not be related: +FAIL: cxg2021 i386 only, might be related ,.,. CXG2021 ACATS 2.5 13-05-27 17:47:57 ---- CXG2021 Check the accuracy of the complex SIN and COS functions. * CXG2021 Identity_2_Test 3 0: Cos(( 1.60300E+01, 1.60000E+01)) imaginary part actual: 1.40623E+06 expected: 1.40622E+06 difference: 4.00000E+00 max err: 3.68797E+00 efactor: 1.40623E+06. **** CXG2021 FAILED ****************************. * The new gnat.dg/fp_exception.adb test fails on Solaris 9 and 10/x86, Solaris 9 and 11/SPARC: +FAIL: gnat.dg/fp_exception.adb execution test raised CONSTRAINT_ERROR : SIGFPE I haven't yet checked what might be going on. Rainer > 2013-05-23 Eric Botcazou <ebotcazou@adacore.com> > > libgcc/ > * config/sparc/sol2-unwind.h (MD_FALLBACK_FRAME_STATE_FOR): Do not set > fs->signal_frame for SIGFPE raised for IEEE-754 exceptions. > * config/i386/sol2-unwind.h (x86_fallback_frame_state): Likewise. > > > 2013-05-23 Eric Botcazou <ebotcazou@adacore.com> > > * gnat.dg/fp_exception.adb: New test.
> I've included the patch in my Solaris bootstraps this weekend, and > results don't look good: > > * On Solaris 9/x86 and Solaris 10/x86 (both 32- and 64-bit), I get a new > ACATS failure which may or may not be related: > > +FAIL: cxg2021 > > i386 only, might be related > > ,.,. CXG2021 ACATS 2.5 13-05-27 17:47:57 > ---- CXG2021 Check the accuracy of the complex SIN and COS functions. > * CXG2021 Identity_2_Test 3 0: Cos(( 1.60300E+01, 1.60000E+01)) > imaginary part actual: 1.40623E+06 expected: > 1.40622E+06 difference: 4.00000E+00 max err: > 3.68797E+00 efactor: 1.40623E+06. > **** CXG2021 FAILED ****************************. Weird, this test shouldn't exercise the unwinder at all. This might be related to the patch mentioned below... > * The new gnat.dg/fp_exception.adb test fails on Solaris 9 and 10/x86, > Solaris 9 and 11/SPARC: > > +FAIL: gnat.dg/fp_exception.adb execution test > > raised CONSTRAINT_ERROR : SIGFPE Patch collision. After 2013-05-24 Eric Botcazou <ebotcazou@adacore.com> * gcc-interface/gigi.h (gnat_init_gcc_fp): Declare. * gcc-interface/trans.c (gigi): Call it. * gcc-interface/misc.c (gnat_init_gcc_fp): New function. you need to compile with -ftrapping-math; revised testcase attached.
Eric Botcazou <ebotcazou@adacore.com> writes: >> * The new gnat.dg/fp_exception.adb test fails on Solaris 9 and 10/x86, >> Solaris 9 and 11/SPARC: >> >> +FAIL: gnat.dg/fp_exception.adb execution test >> >> raised CONSTRAINT_ERROR : SIGFPE > > Patch collision. After > > 2013-05-24 Eric Botcazou <ebotcazou@adacore.com> > > * gcc-interface/gigi.h (gnat_init_gcc_fp): Declare. > * gcc-interface/trans.c (gigi): Call it. > * gcc-interface/misc.c (gnat_init_gcc_fp): New function. > > you need to compile with -ftrapping-math; revised testcase attached. This works. Patch is ok with that revision. Thanks. Rainer
> i386 only, might be related > > ,.,. CXG2021 ACATS 2.5 13-05-27 17:47:57 > ---- CXG2021 Check the accuracy of the complex SIN and COS functions. > * CXG2021 Identity_2_Test 3 0: Cos(( 1.60300E+01, 1.60000E+01)) > imaginary part actual: 1.40623E+06 expected: > 1.40622E+06 difference: 4.00000E+00 max err: > 3.68797E+00 efactor: 1.40623E+06. > **** CXG2021 FAILED ****************************. I can reproduce with the unpatched compiler. Investigating...
Index: config/sparc/sol2-unwind.h =================================================================== --- config/sparc/sol2-unwind.h (revision 199191) +++ config/sparc/sol2-unwind.h (working copy) @@ -403,7 +403,12 @@ MD_FALLBACK_FRAME_STATE_FOR (struct _Unw fs->retaddr_column = 0; fs->regs.reg[0].how = REG_SAVED_OFFSET; fs->regs.reg[0].loc.offset = (long)shifted_ra_location - new_cfa; - fs->signal_frame = 1; + + /* SIGFPE for IEEE-754 exceptions is delivered after the faulting insn + rather than before it, so don't set fs->signal_frame in that case. + We test whether the cexc field of the FSR is zero. */ + if ((mctx->fpregs.fpu_fsr & 0x1f) == 0) + fs->signal_frame = 1; return _URC_NO_REASON; } Index: config/i386/sol2-unwind.h =================================================================== --- config/i386/sol2-unwind.h (revision 199190) +++ config/i386/sol2-unwind.h (working copy) @@ -249,7 +249,12 @@ x86_fallback_frame_state (struct _Unwind fs->regs.reg[8].how = REG_SAVED_OFFSET; fs->regs.reg[8].loc.offset = (long)&mctx->gregs[EIP] - new_cfa; fs->retaddr_column = 8; - fs->signal_frame = 1; + + /* SIGFPE for IEEE-754 exceptions is delivered after the faulting insn + rather than before it, so don't set fs->signal_frame in that case. + We test whether the ES field of the Status Register is zero. */ + if ((mctx->fpregs.fp_reg_set.fpchip_state.status & 0x80) == 0) + fs->signal_frame = 1; return _URC_NO_REASON; }