search for: fpscr

> ~/Desktop/Sanjeev/LLVM/llvm-2.7/Release/lib/libLLVMgold.so --eh-frame-hdr > -melf_i386 -dynamic-linker /lib/ld-linux.so.2 /usr/lib/crt1.o Ok, this way you're generating code for x86 > /usr/lib/crti.o > /usr/local/lib/gcc/i686-pc-linux-gnu/4.2.0/crtbegin.o > -L/usr/local/lib/gcc/i686-pc-linux-gnu/4.2.0  -L/usr/local/lib -lgcc > --as-needed -lgcc_s --no-as-needed -lc -lgcc

...e -I../.././gcc/../libcpp/include -I../.././gcc/../libdecnumber -I../libdecnumber -I/home/jal/llvm-2.7/include -DL_mulsc3 -fvisibility=hidden -DHIDE_EXPORTS -c ../.././gcc/libgcc2.c -o libgcc/./_mulsc3.o /tmp/ccmyj0Hi.s: Assembler messages: /tmp/ccmyj0Hi.s:60: Error: bad instruction `vmrs apsr_nzcv,fpscr' /tmp/ccmyj0Hi.s:62: Error: bad instruction `vmrsvs apsr_nzcv,fpscr' /tmp/ccmyj0Hi.s:71: Error: bad instruction `vmrs apsr_nzcv,fpscr' /tmp/ccmyj0Hi.s:76: Error: bad instruction `vmrs apsr_nzcv,fpscr' /tmp/ccmyj0Hi.s:83: Error: bad instruction `vmrs apsr_nzcv,fpscr' /tmp/ccmyj0H...

Sorry for not explaining well. After compiling with g++-cross g++-cross -c a.c I do link using this command /gold_binutils/build/gold/ld-new -plugin ~/Desktop/Sanjeev/LLVM/llvm-2.7/Release/lib/libLLVMgold.so --eh-frame-hdr -melf_i386 -dynamic-linker /lib/ld-linux.so.2 /usr/lib/crt1.o /usr/lib/crti.o /usr/local/lib/gcc/i686-pc-linux-gnu/4.2.0/crtbegin.o

Hello, This is the second version of this patch series. I only implement the VPF context switch support for arm32 and add dummy function to avoid compilation on arm64. I have switched the order of the patch because the old second one can be applied alone and the patch are cleaner :). For all the changes see each patch. Cheers, Julien Grall (2): xen/arm: don''t enable VFP on XEN

Peter, Could you please comment on: http://llvm.org/bugs/show_bug.cgi?id=12757 Specifically, gcc seems to allow this: int __flt_rounds() { unsigned long fpscr; __asm__ volatile("mffs %0" : "=f"(fpscr)); return fpscr; } My reading of this is that gcc allocates a floating-point register to hold the result of the mffs instruction, and then bit casts (and truncates?) the result into the unsigned long variable. Is this correct, and if s...

> Nope, you want non-trapping instructions. If you use trapping > instructions, C99 functions like isgreater will not work correctly with > NAN's. How do I know when to use a trapping instruction? For example consider this C function: ------------------------ int f(float a, float b) { return a <= b; } ------------------------ gcc uses fcmpes instead of fcmps... >

Hi, > James, is that a correct assessment? Yes, it is also my belief that the only way ARMv7 NEON differs from IEEE754 is lack of denormal support. James > On 11 Feb 2016, at 10:53, Renato Golin <renato.golin at linaro.org> wrote: > > Hal, > > I had a read on the ARM ARM about VFP and SIMD FP semantics and my > analysis is that NEON's only problem is the

Hi Oleg, On 01/09/14 18:46, Oleg Ranevskyy wrote: > Hi Duncan, > > I looked through the IEEE standard and here is what I found: > > *6.2 Operations with NaNs* > /"For an operation with quiet NaN inputs, other than maximum and minimum > operations, if a floating-point result is to be delivered the result shall be a > quiet NaN which should be one of the input

...mpare equal to x when doing floating point comparisons? fadd x, –0.0 always has the same bit pattern as x, unless: (a) x is a signaling NaN on a platform that supports them. (b) x is a quiet NaN on a platform that does not propagate NaN payloads (e.g. ARM with "default nan" bit set in fpscr). (c) x is +0.0 and the rounding mode is round down. – Steve

...ayloads that match exactly what the target would generate. —Owen > On Sep 16, 2014, at 10:30 AM, Oleg Ranevskyy <llvm.mail.list at gmail.com> wrote: > > Hi Duncan, > > I reread everything we've discussed so far and would like to pay closer attention to the the ARM's FPSCR register mentioned by Stephen. > It's really possible on ARM systems that floating point operations on one or more qNaN operands return a NaN different from the operands. I.e. operand NaN is not propagated. This happens when the "default NaN" flag is set in the FPSCR (floating poin...

On Fri, 2012-04-27 at 14:54 -0500, Hal Finkel wrote: > There is a comment in the file which reads: > > /* The weird 'i#*X' constraints on the following suppress a gcc > warning when __excepts is not a constant. Otherwise, they mean the > same as just plain 'i'. */ [sinp] > ("mtfsb0 %s0" : : "i#*X"(__builtin_ffs (__excepts))); [snip]

...se you get a trap? Because you either get a trap (if the invalid exception is unmasked), or the invalid flag is set and the result is a quiet NaN (much more common). >> (b) x is a quiet NaN on a platform that does not propagate NaN payloads (e.g. ARM with "default nan" bit set in fpscr). > > What do you get in this case? A NaN whose “payload” (i.e. the bits in what would be the significand field of a normal number) may be different from those of the input NaN. >> (c) x is +0.0 and the rounding mode is round down. > > So far rounding modes were always ignore...

Hello, I am not sure whether this is a clang issue, an LLVM issue, or both; but clang chokes when parsing expanded macros from the glibc /usr/include/bits/fenvinline.h with an error like: ./boost/math/tools/config.hpp:279:10: error: invalid input constraint 'i#*X' in asm feclearexcept(FE_ALL_EXCEPT); ^ /usr/include/bits/fenvinline.h:56:11: note: expanded from macro

...>>> On Sep 16, 2014, at 10:30 AM, Oleg Ranevskyy >>> <llvm.mail.list at gmail.com> wrote: >>> >>> Hi Duncan, >>> >>> I reread everything we've discussed so far and would like to pay >>> closer attention to the the ARM's FPSCR register mentioned by Stephen. >>> It's really possible on ARM systems that floating point operations >>> on one or more qNaN operands return a NaN different from the >>> operands. I.e. operand NaN is not propagated. This happens when the >>> "default...

Have a look at how the ARM backend handles the CPSR register. It sounds like what you're really looking for is liveness of that status register not to be clobbered between the arithmetic instruction you're inspecting and the instruction that reads that register. Cheers, Jon On 9/30/14 12:39 PM, Jingyue Wu wrote: > I can't think of any NVPTX intrinsic that disallow even

...gt;>> <llvm.mail.list at gmail.com> wrote: >>>>> >>>>> Hi Duncan, >>>>> >>>>> I reread everything we've discussed so far and would like to pay >>>>> closer >>>>> attention to the the ARM's FPSCR register mentioned by Stephen. >>>>> It's really possible on ARM systems that floating point operations >>>>> on one or >>>>> more qNaN operands return a NaN different from the operands. I.e. >>>>> operand >>>>> NaN is...

...ther than to represent a particular register. The 0x01 would be the encoding used in generating the binary. The D0 has id 14 on ARM because there are 13 other registers preceding it: namespace ARM { enum { NoRegister, APSR = 1, APSR_NZCV = 2, CPSR = 3, FPEXC = 4, FPINST = 5, FPSCR = 6, FPSCR_NZCV = 7, FPSID = 8, ITSTATE = 9, LR = 10, PC = 11, SP = 12, SPSR = 13, D0 = 14, ... -Krzysztof -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

...t; Because you either get a trap (if the invalid exception is unmasked), or the invalid flag is set and the result is a quiet NaN (much more common). >> >>>> (b) x is a quiet NaN on a platform that does not propagate NaN payloads (e.g. ARM with "default nan" bit set in fpscr). >>> What do you get in this case? >> A NaN whose “payload” (i.e. the bits in what would be the significand field of a normal number) may be different from those of the input NaN. >> >>>> (c) x is +0.0 and the rounding mode is round down. >>> So far roun...

Dear all, in my TestRegisterInfo.td file, I defined a register like this: class TestReg<bits<6> enc, string name> : Register<name> { let HWEncoding{5-0} = enc; let Namespace = "TEST"; } def D0 : TestReg<0x01, "d0">, DwarfRegNum<[1]>; but when I compile, the result I have in TestGenAsmMatcher.inc is this: case 'd': // 7

...ptimized IR to codegen: > define i32 @is_nan(float %x) { > %cmp = fcmp uno float %x, 0.000000e+00 > %r = zext i1 %cmp to i32 > ret i32 %r > } > > $ llc -o - fpexception.ll -mtriple=armv7a > vmov s0, r0 > mov r0, #0 > vcmpe.f32 s0, s0 > vmrs APSR_nzcv, fpscr > movwvs r0, #1 > bx lr > > We produced "vcmpe" for code that should never cause an FP exception. ARM > codegen bug? sorry, the arm code gen is right here, the bug is in clang. > > On Tue, Oct 1, 2019 at 5:45 AM Kristof Beyls <Kristof.Beyls at arm.com> w...