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llvm-project/llvm/test/Transforms/LoopVersioningLICM/loopversioningLICM2.ll

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New Loop Versioning LICM Pass Summary: When alias analysis is uncertain about the aliasing between any two accesses, it will return MayAlias. This uncertainty from alias analysis restricts LICM from proceeding further. In cases where alias analysis is uncertain we might use loop versioning as an alternative. Loop Versioning will create a version of the loop with aggressive aliasing assumptions in addition to the original with conservative (default) aliasing assumptions. The version of the loop making aggressive aliasing assumptions will have all the memory accesses marked as no-alias. These two versions of loop will be preceded by a memory runtime check. This runtime check consists of bound checks for all unique memory accessed in loop, and it ensures the lack of memory aliasing. The result of the runtime check determines which of the loop versions is executed: If the runtime check detects any memory aliasing, then the original loop is executed. Otherwise, the version with aggressive aliasing assumptions is used. The pass is off by default and can be enabled with command line option -enable-loop-versioning-licm. Reviewers: hfinkel, anemet, chatur01, reames Subscribers: MatzeB, grosser, joker.eph, sanjoy, javed.absar, sbaranga, llvm-commits Differential Revision: http://reviews.llvm.org/D9151 llvm-svn: 259986
2016-02-06 15:47:48 +08:00
; RUN: opt < %s -O1 -S -loop-versioning-licm -licm -debug-only=loop-versioning-licm -disable-loop-unrolling 2>&1 | FileCheck %s
Corrected tests for Loop Versioning LICM, by adding “REQUIRES: asserts”. Earlier they were failing under no-assert build. llvm-svn: 259989
2016-02-06 20:34:41 +08:00
; REQUIRES: asserts
New Loop Versioning LICM Pass Summary: When alias analysis is uncertain about the aliasing between any two accesses, it will return MayAlias. This uncertainty from alias analysis restricts LICM from proceeding further. In cases where alias analysis is uncertain we might use loop versioning as an alternative. Loop Versioning will create a version of the loop with aggressive aliasing assumptions in addition to the original with conservative (default) aliasing assumptions. The version of the loop making aggressive aliasing assumptions will have all the memory accesses marked as no-alias. These two versions of loop will be preceded by a memory runtime check. This runtime check consists of bound checks for all unique memory accessed in loop, and it ensures the lack of memory aliasing. The result of the runtime check determines which of the loop versions is executed: If the runtime check detects any memory aliasing, then the original loop is executed. Otherwise, the version with aggressive aliasing assumptions is used. The pass is off by default and can be enabled with command line option -enable-loop-versioning-licm. Reviewers: hfinkel, anemet, chatur01, reames Subscribers: MatzeB, grosser, joker.eph, sanjoy, javed.absar, sbaranga, llvm-commits Differential Revision: http://reviews.llvm.org/D9151 llvm-svn: 259986
2016-02-06 15:47:48 +08:00
;
; Test to confirm loop is a good candidate for LoopVersioningLICM
; It also confirms invariant moved out of loop.
;
; CHECK: Loop: Loop at depth 2 containing: %for.body3.us<header><latch><exiting>
; CHECK-NEXT: Loop Versioning found to be beneficial
;
; CHECK: for.cond1.for.inc17_crit_edge.us.loopexit5: ; preds = %for.body3.us
; CHECK-NEXT: %add14.us.lcssa = phi float [ %add14.us, %for.body3.us ]
Make MDNode::intersect faster than O(n * m) It is pretty easy to get it down to O(nlogn + mlogm). This implementation has the added benefit of automatically deduplicating entries between the two sets. llvm-svn: 278837
2016-08-17 02:48:37 +08:00
; CHECK-NEXT: store float %add14.us.lcssa, float* %arrayidx.us, align 4, !alias.scope !0, !noalias !0
New Loop Versioning LICM Pass Summary: When alias analysis is uncertain about the aliasing between any two accesses, it will return MayAlias. This uncertainty from alias analysis restricts LICM from proceeding further. In cases where alias analysis is uncertain we might use loop versioning as an alternative. Loop Versioning will create a version of the loop with aggressive aliasing assumptions in addition to the original with conservative (default) aliasing assumptions. The version of the loop making aggressive aliasing assumptions will have all the memory accesses marked as no-alias. These two versions of loop will be preceded by a memory runtime check. This runtime check consists of bound checks for all unique memory accessed in loop, and it ensures the lack of memory aliasing. The result of the runtime check determines which of the loop versions is executed: If the runtime check detects any memory aliasing, then the original loop is executed. Otherwise, the version with aggressive aliasing assumptions is used. The pass is off by default and can be enabled with command line option -enable-loop-versioning-licm. Reviewers: hfinkel, anemet, chatur01, reames Subscribers: MatzeB, grosser, joker.eph, sanjoy, javed.absar, sbaranga, llvm-commits Differential Revision: http://reviews.llvm.org/D9151 llvm-svn: 259986
2016-02-06 15:47:48 +08:00
; CHECK-NEXT: br label %for.cond1.for.inc17_crit_edge.us
;
define i32 @foo(float* nocapture %var2, float** nocapture readonly %var3, i32 %itr) #0 {
entry:
%cmp38 = icmp sgt i32 %itr, 1
br i1 %cmp38, label %for.body3.lr.ph.us, label %for.end19
for.body3.us: ; preds = %for.body3.us, %for.body3.lr.ph.us
%0 = phi float [ %.pre, %for.body3.lr.ph.us ], [ %add14.us, %for.body3.us ]
%indvars.iv = phi i64 [ 1, %for.body3.lr.ph.us ], [ %indvars.iv.next, %for.body3.us ]
%1 = trunc i64 %indvars.iv to i32
%conv.us = sitofp i32 %1 to float
%add.us = fadd float %conv.us, %0
%arrayidx7.us = getelementptr inbounds float, float* %3, i64 %indvars.iv
store float %add.us, float* %arrayidx7.us, align 4
%2 = load float, float* %arrayidx.us, align 4
%add14.us = fadd float %2, %add.us
store float %add14.us, float* %arrayidx.us, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, %itr
br i1 %exitcond, label %for.cond1.for.inc17_crit_edge.us, label %for.body3.us
for.body3.lr.ph.us: ; preds = %entry, %for.cond1.for.inc17_crit_edge.us
%indvars.iv40 = phi i64 [ %indvars.iv.next41, %for.cond1.for.inc17_crit_edge.us ], [ 1, %entry ]
%arrayidx.us = getelementptr inbounds float, float* %var2, i64 %indvars.iv40
%arrayidx6.us = getelementptr inbounds float*, float** %var3, i64 %indvars.iv40
%3 = load float*, float** %arrayidx6.us, align 8
%.pre = load float, float* %arrayidx.us, align 4
br label %for.body3.us
for.cond1.for.inc17_crit_edge.us: ; preds = %for.body3.us
%indvars.iv.next41 = add nuw nsw i64 %indvars.iv40, 1
%lftr.wideiv42 = trunc i64 %indvars.iv.next41 to i32
%exitcond43 = icmp eq i32 %lftr.wideiv42, %itr
br i1 %exitcond43, label %for.end19, label %for.body3.lr.ph.us
for.end19: ; preds = %for.cond1.for.inc17_crit_edge.us, %entry
ret i32 0
}