RPCSX/llvm
1
0
Fork 0
mirror of https://github.com/RPCSX/llvm.git synced 2025-03-01 09:26:22 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

[LVI] Fix a bug with a guard being the very first instruction in a BB not taken into account

Browse Source 
While looking for guards use reverse iterator and scan up to rend() not to begin()


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284827 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Artur Pilipenko 2016-10-21 15:02:21 +00:00
parent 73cda08c45
commit d193fb5457
2 changed files with 21 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
lib/Analysis/LazyValueInfo.cpp
View File

@ -978,12 +978,11 @@ void LazyValueInfoImpl::intersectAssumeOrGuardBlockValueConstantRange(
if (!GuardDecl || GuardDecl->use_empty()) if (!GuardDecl || GuardDecl->use_empty())
return; return;
for (BasicBlock::iterator I = BBI->getIterator(), for (Instruction &I : make_range(BBI->getIterator().getReverse(),
E = BBI->getParent()->begin(); I != E; I--) { BBI->getParent()->rend())) {
Value *Cond = nullptr; Value *Cond = nullptr;
if (!match(&*I, m_Intrinsic<Intrinsic::experimental_guard>(m_Value(Cond)))) if (match(&I, m_Intrinsic<Intrinsic::experimental_guard>(m_Value(Cond))))
continue; BBLV = intersect(BBLV, getValueFromCondition(Val, Cond));
BBLV = intersect(BBLV, getValueFromCondition(Val, Cond));
} }
} }

17
test/Transforms/CorrelatedValuePropagation/guards.ll
View File

@ -93,3 +93,20 @@ continue:
%result = or i1 %dead, %alive %result = or i1 %dead, %alive
ret i1 %result ret i1 %result
} }
; Check that we handle the case when the guard is the very first instruction in
; a basic block.
define i1 @test6(i32 %a) {
; CHECK-LABEL: @test6(
; CHECK: %alive = icmp eq i32 %a, 8
; CHECK-NEXT: %result = or i1 false, %alive
%cmp = icmp ult i32 %a, 16
br label %continue
continue:
call void(i1,...) @llvm.experimental.guard(i1 %cmp) [ "deopt"() ]
%dead = icmp eq i32 %a, 16
%alive = icmp eq i32 %a, 8
%result = or i1 %dead, %alive
ret i1 %result
}