| Message ID | b1032edf-0bd1-5404-8870-ebff62cd9178@mentor.com |
|---|---|
| State | New |
| Headers | show |
| Series | [committed,amdgcn] Wait for exit value to write before exiting. | expand |
On 24/05/2019 16:31, Andrew Stubbs wrote: > This patch fixes a bug in which GCN5 devices often fail to return an > exit value because it's not yet been written to memory when the program > exits. The fix is simply to wait for it properly. GCN3 devices did not > demonstrate the problem, but it was technically wrong there also. The > bug was introduced when we stopped waiting for all writes to complete. > > I've also taken the opportunity to adjust gcn-run such that a similar > issue can't go unnoticed for so long, in future. Now backported to gcc-9-branch. Andrew
GCN: Wait for exit value to write before exiting. 2019-05-24 Andrew Stubbs <ams@codesourcery.com> gcc/ * config/gcn/gcn-run.c (main): Set a non-zero return value if the kernel does not exit cleanly. * config/gcn/gcn.md (gcn_return): Insert s_waitcnt before s_dcache_wb. diff --git a/gcc/config/gcn/gcn-run.c b/gcc/config/gcn/gcn-run.c index 84718f42846..21852d78bc5 100644 --- a/gcc/config/gcn/gcn-run.c +++ b/gcc/config/gcn/gcn-run.c @@ -853,7 +853,10 @@ main (int argc, char *argv[]) unsigned int upper = (return_value & ~0xffff) >> 16; if (upper == 0xcafe) - printf ("Kernel exit value was never set\n"); + { + printf ("Kernel exit value was never set\n"); + return_value = 0xff; + } else if (upper == 0xffff) ; /* Set by exit. */ else if (upper == 0) diff --git a/gcc/config/gcn/gcn.md b/gcc/config/gcn/gcn.md index 2b805a73c56..1f06d0bd5cc 100644 --- a/gcc/config/gcn/gcn.md +++ b/gcc/config/gcn/gcn.md @@ -784,10 +784,10 @@ if (cfun && cfun->machine && cfun->machine->normal_function) return "s_setpc_b64\ts[18:19]"; else - return "s_dcache_wb\;s_endpgm"; + return "s_waitcnt\tlgkmcnt(0)\;s_dcache_wb\;s_endpgm"; } [(set_attr "type" "sop1") - (set_attr "length" "8")]) + (set_attr "length" "12")]) (define_expand "call" [(parallel [(call (match_operand 0 "")