[Bug tree-optimization/87214] New: [9 Regression] SPEC CPU2017, CPU2006 520/620, 403 runfails after r263772 with march=skylake-avx512

[alexander.nesterovskiy at intel dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87214

            Bug ID: 87214
           Summary: [9 Regression] SPEC CPU2017, CPU2006 520/620, 403
                    runfails after r263772 with march=skylake-avx512
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: alexander.nesterovskiy at intel dot com
  Target Milestone: ---

There are runfails for the following benchmarks since r263772:
SPEC2017 520/620: (Segmentation fault, minimal optset to reproduce: "-O3
-march=skylake-avx512 -flto")
SPEC2006 445: (SPEC miscompare, minimal optset to reproduce: "-O3
-march=skylake-avx512")

Running 520.omnetpp_r under GDB:
---
...
Program received signal SIGSEGV, Segmentation fault.
0x00000000004a611e in isName (s=<optimized out>, this=<optimized out>) at
simulator/ccomponent.cc:143
143             if (paramv[i].isName(parname))
(gdb) backtrace
#0  0x00000000004a611e in isName (s=<optimized out>, this=<optimized out>) at
simulator/ccomponent.cc:143
#1  cComponent::findPar (this=0x7ffff6633380, parname=0x7ffff6603548 "bs") at
simulator/ccomponent.cc:143
#2  0x00000000004a87b3 in cComponent::par(char const*) () at
simulator/ccomponent.cc:133
#3  0x00000000004b676d in cNEDNetworkBuilder::doParam(cComponent*,
ParamElement*, bool) () at simulator/cnednetworkbuilder.cc:179
#4  0x00000000004b8610 in doParams (isSubcomponent=false, paramsNode=<optimized
out>, component=0x7ffff6633380, this=0x7fffffffaaf0) at
simulator/cnednetworkbuilder.cc:139
#5  cNEDNetworkBuilder::addParametersAndGatesTo(cComponent*, cNEDDeclaration*)
() at simulator/cnednetworkbuilder.cc:105
#6  0x000000000048843b in addParametersAndGatesTo (module=0x7ffff6633380,
this=<optimized out>) at <GCC_PATH>/include/c++/9.0.0/bits/stl_tree.h:211
#7  cModuleType::create(char const*, cModule*, int, int) () at
simulator/ccomponenttype.cc:156
#8  0x000000000045916f in setupNetwork (network=<optimized out>,
this=0x7ffff653bc40) at simulator/cnamedobject.h:117
#9  Cmdenv::run() () at simulator/cmdenv.cc:253
#10 0x00000000005186ec in EnvirBase::run(int, char**, cConfiguration*) () at
simulator/envirbase.cc:230
#11 0x000000000043d60d in setupUserInterface(int, char**, cConfiguration*)
[clone .constprop.112] () at simulator/startup.cc:234
#12 0x000000000042446a in main (argc=1, argv=0x7fffffffb1c8) at
simulator/main.cc:39
---

403.gcc miscompares: 200.s, g23.s, scilab.s.
For example:
---
$ diff -u g23_ref.s g23.s | head -n 16
--- g23_ref.s
+++ g23.s
@@ -1746,19 +1746,19 @@
        testq   %rbx, %rbx
        jne     .L904
        movq    %r12, %rdx
-       xorl    %r8d, %r8d
+       xorl    %esi, %esi
        negq    %rdx
 .L905:
        addq    %rcx, %rdx
-       leaq    (%rax,%r8), %rax
+       leaq    (%rax,%rsi), %rax
        leaq    1(%rdx), %rcx
-       cmpq    %r8, %rax
+       cmpq    %rsi, %rax

---

Unfortunately I didn't manage to create a reproducer.