[llvm-dev] [OpenMP][AArch64][GlobalISel] AArch64 OMPT tests failing

[David Greene via llvm-dev]

We're seeing OMPT tests fail on AArch64:

    libomp :: ompt/misc/control_tool.c
    libomp :: ompt/synchronization/master.c
    libomp :: ompt/synchronization/taskwait.c

The failure mode is similar for all of them:

openmp/runtime/test/ompt/misc/control_tool.c:26:17: error: CHECK-NEXT: expected string not found in input
 // CHECK-NEXT: {{^}}[[MASTER_ID]]: current_address={{.*}}[[RETURN_ADDRESS]]
                ^
<stdin>:9:1: note: scanning from here
281474976710657: current_address=0x402cf4 or 0x402cf0
^
<stdin>:9:1: note: with variable "MASTER_ID" equal to "281474976710657"
281474976710657: current_address=0x402cf4 or 0x402cf0
^
<stdin>:9:1: note: with variable "RETURN_ADDRESS" equal to "0x402cec"
281474976710657: current_address=0x402cf4 or 0x402cf0
^
<stdin>:9:13: note: possible intended match here
281474976710657: current_address=0x402cf4 or 0x402cf0
            ^

I bisected the control_tool.c failure to:

3834f852008a82e361d325ec7b1c3fee0dc783c3 is the first bad commit
commit 3834f852008a82e361d325ec7b1c3fee0dc783c3
Author: Petr Pavlu <petr.pavlu at arm.com>
Date:   Thu Nov 29 12:56:32 2018 +0000

    [GlobalISel] Make EnableGlobalISel always set when GISel is enabled
    
    Change meaning of TargetOptions::EnableGlobalISel. The flag was
    previously set only when a target switched on GlobalISel but it is now
    always set when the GlobalISel pipeline is enabled. This makes the flag
    consistent with TargetOptions::EnableFastISel and allows its use in
    other parts of the compiler to determine when GlobalISel is enabled.
    
    The EnableGlobalISel flag had previouly only one use in
    TargetPassConfig::isGlobalISelAbortEnabled(). The method used its value
    to determine if GlobalISel was enabled by a target and returned false in
    such a case. To preserve the current behaviour, a new flag
    TargetOptions::GlobalISelAbort is introduced to separately record the
    abort behaviour.
    
    Differential Revision: https://reviews.llvm.org/D54518
    
    
    git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347861 91177308-0d34-0410-b5e6-96231b3b80d8

Is it possible this commit changed the behavior of clang's
-fno-experimental-isel?  The OpenMP tests use that flag.

                            -David