6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-14 11:32:34 +00:00
Code Issues Projects Releases Wiki Activity

Fix a bug in SelectionDAG scheduling backtracking code: PR22304.

Browse Source 
It can happen (by line CurSU->isPending = true; // This SU is not in
AvailableQueue right now.) that a SUnit is mark as available but is
not in the AvailableQueue. For SUnit being selected for scheduling
both conditions must be met.

This patch mainly defensively protects from invalid removing a node
from a queue. Sometimes nodes are marked isAvailable but are not in
the queue because they have been defered due to some hazard.

Patch by Pawel Bylica!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233351 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Andrew Trick 2015-03-27 03:44:13 +00:00
parent b3ad90eacc
commit 18fc42ab12
2 changed files with 53 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
View File

@ -1423,9 +1423,10 @@ SUnit *ScheduleDAGRRList::PickNodeToScheduleBottomUp() {
// If one or more successors has been unscheduled, then the current
// node is no longer available.
if (!TrySU->isAvailable)
if (!TrySU->isAvailable || !TrySU->NodeQueueId)
CurSU = AvailableQueue->pop();
else {
// Available and in AvailableQueue
AvailableQueue->remove(TrySU);
CurSU = TrySU;
}

51
test/CodeGen/Generic/scheduler-backtracking.ll Normal file
View File

@ -0,0 +1,51 @@
; RUN: llc < %s -pre-RA-sched=list-ilp | FileCheck %s
; RUN: llc < %s -pre-RA-sched=list-hybrid | FileCheck %s
; RUN: llc < %s -pre-RA-sched=source | FileCheck %s
; RUN: llc < %s -pre-RA-sched=list-burr | FileCheck %s
; RUN: llc < %s -pre-RA-sched=linearize | FileCheck %s
; PR22304 https://llvm.org/bugs/show_bug.cgi?id=22304
; Tests checking backtracking in source scheduler. llc used to crash on them.
; CHECK-LABEL: test1
define i256 @test1(i256 %a) {
%b = add i256 %a, 1
%m = shl i256 %b, 1
%p = add i256 %m, 1
%v = lshr i256 %b, %p
%t = trunc i256 %v to i1
%c = shl i256 1, %p
%f = select i1 %t, i256 undef, i256 %c
ret i256 %f
}
; CHECK-LABEL: test2
define i256 @test2(i256 %a) {
%b = sub i256 0, %a
%c = and i256 %b, %a
%d = call i256 @llvm.ctlz.i256(i256 %c, i1 false)
ret i256 %d
}
; CHECK-LABEL: test3
define i256 @test3(i256 %n) {
%m = sub i256 -1, %n
%x = sub i256 0, %n
%y = and i256 %x, %m
%z = call i256 @llvm.ctlz.i256(i256 %y, i1 false)
ret i256 %z
}
declare i256 @llvm.ctlz.i256(i256, i1) nounwind readnone
; CHECK-LABEL: test4
define i64 @test4(i64 %a, i64 %b) {
%r = zext i64 %b to i256
%u = add i256 %r, 1
%w = and i256 %u, 1461501637330902918203684832716283019655932542975
%x = zext i64 %a to i256
%c = icmp uge i256 %w, %x
%y = select i1 %c, i64 0, i64 1
%z = add i64 %y, 1
ret i64 %z
}