maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[IVDescriptors] Skip FOR where we have multiple sink points for now. 

This fixes a crash with instructions where multiple operands are
first-order-recurrences.
This commit is contained in:
Florian Hahn 2019-11-28 22:08:05 +01:00
parent c671639af6
commit ec3efcf11f
2 changed files with 37 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
llvm/lib/Analysis/IVDescriptors.cpp
View File

@ -721,6 +721,13 @@ bool RecurrenceDescriptor::isFirstOrderRecurrence(
if (I->getParent()->getTerminator() == I)
return false;
// Do not try to sink an instruction multiple times (if multiple operands
// are first order recurrences).
// TODO: We can support this case, by sinking the instruction after the
// 'deepest' previous instruction.
if (SinkAfter.find(I) != SinkAfter.end())
return false;
if (DT->dominates(Previous, I)) // We already are good w/o sinking.
return true;

30
llvm/test/Transforms/LoopVectorize/first-order-recurrence-complex.ll
View File

@ -243,3 +243,33 @@ for:
exit:
ret void
}
; TODO: We should be able to sink %tmp38 after %tmp60.
define void @instruction_with_2_FOR_operands() {
; CHECK-LABEL: define void @instruction_with_2_FOR_operands(
; CHECK-NEXT: bb:
; CHECK-NEXT: br label %bb13
; CHECK-LABEL: bb13:
; CHECK: br i1 %tmp12, label %bb13, label %bb74
; CHECK-LABEL: bb74:
; CHECK-NEXT: ret void
;
bb:
br label %bb13
bb13: ; preds = %bb13, %bb
%tmp37 = phi float [ %tmp60, %bb13 ], [ undef, %bb ]
%tmp27 = phi float [ %tmp49, %bb13 ], [ undef, %bb ]
%indvars.iv = phi i64 [ %indvars.iv.next, %bb13 ], [ 0, %bb ]
%tmp38 = fmul fast float %tmp37, %tmp27
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%tmp49 = load float, float* undef, align 4
%tmp60 = load float, float* undef, align 4
%tmp12 = icmp slt i64 %indvars.iv, undef
br i1 %tmp12, label %bb13, label %bb74
bb74: ; preds = %bb13
ret void
}