add launchpad bug reports without comments

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+VLLDM/VLSTM trigger UsageFault in the Secure Mode
+
+The VLLDM/VLSTM instructions trigger UsageFault when they are supposed to behave as NOP.
+
+Version: 
+$ qemu-system-arm --version                                                                               QEMU emulator version 2.11.93
+
+VLLDM and VLSTM are instructions newly added to ARMv8-M Mainline Profile. Although they are FP instructions and the FP support of the M profile is not implemented by QEMU, the Armv8-M Architecture Reference Manual specifies that they should behave as NOP even in this case:
+
+C2.4.268 VLLDM:
+
+> If the Floating-point Extension is not implemented, this instruction is available in Secure state, but behaves as a NOP.
+
+C2.4.269 VLSTM:
+
+> If the Floating-point Extension is not implemented, this instruction is available in Secure state, but behaves as a NOP.
+
+VLLDM and VLSTM are generated automatically by the compiler to save and restore the floating point registers (in a lazy manner) during a Non-Secure function call. An example is shown below:
+
+10000064 <__gnu_cmse_nonsecure_call>:
+10000064:       e92d 4fe0       stmdb   sp!, {r5, r6, r7, r8, r9, sl, fp, lr}
+10000068:       4627            mov     r7, r4
+1000006a:       46a0            mov     r8, r4
+1000006c:       46a1            mov     r9, r4
+1000006e:       46a2            mov     sl, r4
+10000070:       46a3            mov     fp, r4
+10000072:       46a4            mov     ip, r4
+10000074:       b0a2            sub     sp, #136        ; 0x88
+10000076:       ec2d 0a00       vlstm   sp
+1000007a:       f384 8800       msr     CPSR_f, r4
+1000007e:       4625            mov     r5, r4
+10000080:       4626            mov     r6, r4
+10000082:       47a4            blxns   r4
+10000084:       ec3d 0a00       vlldm   sp
+10000088:       b022            add     sp, #136        ; 0x88
+1000008a:       e8bd 8fe0       ldmia.w sp!, {r5, r6, r7, r8, r9, sl, fp, pc}
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