[LoopUnroll] Remap references in peeled iteration

References in cloned blocks must be remapped prior to dominator
calculation.

Differential Revision: https://reviews.llvm.org/D31281

llvm-svn: 298811
This commit is contained in:
Serge Pavlov 2017-03-26 16:46:53 +00:00
parent 12801f1e0f
commit b71bb80c2d
2 changed files with 66 additions and 4 deletions

View File

@ -415,6 +415,11 @@ bool llvm::peelLoop(Loop *L, unsigned PeelCount, LoopInfo *LI,
cloneLoopBlocks(L, Iter, InsertTop, InsertBot, Exit,
NewBlocks, LoopBlocks, VMap, LVMap, DT, LI);
// Remap to use values from the current iteration instead of the
// previous one.
remapInstructionsInBlocks(NewBlocks, VMap);
if (DT) {
// Latches of the cloned loops dominate over the loop exit, so idom of the
// latter is the first cloned loop body, as original PreHeader dominates
@ -437,10 +442,6 @@ bool llvm::peelLoop(Loop *L, unsigned PeelCount, LoopInfo *LI,
F->getBasicBlockList().splice(InsertTop->getIterator(),
F->getBasicBlockList(),
NewBlocks[0]->getIterator(), F->end());
// Remap to use values from the current iteration instead of the
// previous one.
remapInstructionsInBlocks(NewBlocks, VMap);
}
// Now adjust the phi nodes in the loop header to get their initial values

View File

@ -0,0 +1,61 @@
; RUN: opt -S -loop-unroll -unroll-force-peel-count=1 -verify-dom-info <%s
; Check if loop composed of several BBs is peeled correctly.
declare void @funcb()
@Comma = external global i8
define void @funca(i8* readnone %b, i8* readnone %e) {
entry:
%cmp2 = icmp eq i8* %b, %e
br i1 %cmp2, label %for.end, label %for.body.preheader
for.body.preheader:
br label %for.body
for.body:
%b.addr.03 = phi i8* [ %incdec.ptr, %for.inc ], [ %b, %for.body.preheader ]
%0 = load i8, i8* @Comma
%tobool = icmp eq i8 %0, 0
br i1 %tobool, label %for.inc, label %if.then
if.then:
tail call void @funcb()
store i8 1, i8* @Comma
br label %for.inc
for.inc:
%incdec.ptr = getelementptr inbounds i8, i8* %b.addr.03, i64 1
%cmp = icmp eq i8* %incdec.ptr, %e
br i1 %cmp, label %for.end, label %for.body
for.end:
ret void
}
; CHECK_LABEL: @funca
; Peeled iteration
; CHECK: %[[REG1:[0-9]+]] = load i8, i8* @Comma
; CHECK: %[[REG2:.*]] = icmp eq i8 %[[REG1]], 0
; CHECK: br i1 %[[REG2]], label %{{.*}}, label %[[IFTHEN:.*]]
; CHECK: [[IFTHEN]]:
; CHECK: call void @funcb()
; CHECK: store i8 1, i8* @Comma
; CHECK: br label %[[FORINC]]
; CHECK: [[FORINC]]:
; CHECK: %[[REG3:.*]] = getelementptr inbounds i8, i8* %b, i64 1
; CHECK: %[[REG4:.*]] = icmp eq i8* %[[REG3]], %e
; CHECK: br i1 %[[REG4]]
; main body
; CHECK: %[[REG1b:.*]] = load i8, i8* @Comma
; CHECK: %[[REG2b:.*]] = icmp eq i8 %[[REG1b]], 0
; CHECK: br i1 %[[REG2b]], label %{{.*}}, label %[[IFTHENb:.*]]
; CHECK: [[IFTHENb]]:
; CHECK: call void @funcb()
; CHECK: store i8 1, i8* @Comma
; CHECK: br label %[[FORINCb]]
; CHECK: [[FORINCb]]:
; CHECK: %[[REG3b:.*]] = getelementptr inbounds i8, i8* %b, i64 1
; CHECK: %[[REG4b:.*]] = icmp eq i8* %[[REG3b]], %e
; CHECK: br i1 %[[REG4b]]