[Bug tree-optimization/91109] [10 regression][arm] gcc.c-torture/execute/20040709-1.c fails since r273135

[bernd.edlinger at hotmail dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91109

Bernd Edlinger <bernd.edlinger at hotmail dot de> changed:

           What    |Removed                     |Added
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                 CC|                            |bernd.edlinger at hotmail dot de

--- Comment #4 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
hmm, funny, I saw this test case failing since february at least:

https://gcc.gnu.org/ml/gcc-testresults/2019-02/msg02686.html

FAIL: gcc.c-torture/execute/20040709-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  execution test

--with-arch=armv7-a --with-tune=cortex-a9 --with-fpu=vfpv3-d16
--with-float=hard


I have not looked into it before, but
to me it looks like a reload bug:

        str     r6, [r5] <= r5 still valid
        stm     r9, {r0, r1, r2, r3}
        umull   r5, r3, r7, fp <= r5 clobbered
        ldr     r2, [r4, #176]
        lsr     r9, r3, #3
        mov     r3, r0
        eor     r3, r3, r2
        rsb     r9, r9, r9, lsl #4
        tst     r3, r10
        sub     r9, fp, r9
        bne     .L29
        ldrh    r2, [sp, #176]
        ldrh    r3, [r4, #176]
        eor     r2, r2, r3
        ubfx    r2, r2, #0, #12
        cmp     r2, #0
        bne     .L29
        cmp     r9, r9
        bne     .L29
        mla     r6, r8, r6, lr
        ldr     fp, .L79+36
        mla     lr, r8, r6, lr
        ubfx    r6, r6, #16, #11
        bfi     r3, r6, #0, #12
        strh    r3, [r4, #176]  @ movhi
        uxth    r8, r3
        ldm     fp, {r0, r1, r2, r3}
        ubfx    ip, lr, #16, #11
        add     r7, r6, ip
        add     ip, sp, #176
        bfi     r8, r7, #0, #12
        str     lr, [r5]   <= r5 invalid

reload:
(insn 6826 3453 6816 129 (parallel [
            (set (reg:SI 3 r3 [4187])
                (truncate:SI (lshiftrt:DI (mult:DI (zero_extend:DI (reg:SI 11
fp [4186]))
                            (zero_extend:DI (reg:SI 7 r7 [4188])))
                        (const_int 32 [0x20]))))
            (clobber (reg:SI 5 r5 [5970]))
        ]) "20040709-1.c":108:291 70 {*umulsi3_highpart_v6}
     (nil))
[...]
(insn 3509 3530 3531 132 (set (mem/c:SI (reg/f:SI 5 r5 [5715]) [1
s.5566D.5531+0 S4 A32])
        (reg:SI 14 lr [orig:692 D.6083 ] [692])) "20040709-1.c":13:5 654
{*arm_movsi_vfp}
     (nil))