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llvm/
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lib/Transforms/Scalar/
-
Transforms/
-
Scalar/
-
LoopStrengthReduce.cpp
-
test/Transforms/LoopStrengthReduce/AArch64/
-
Transforms/
-
LoopStrengthReduce/
-
AArch64/
1/3
pr47329.ll

Differential D86939

[LSR] Canonicalize a formula before insert it into the list
ClosedPublic

Authored by mdchen on Sep 1 2020, 7:15 AM.

Download Raw Diff

Details

Reviewers

qcolombet
mkazantsev
amehsan

Commits

rG78071fb52456: [LSR] Canonicalize a formula before insert it into the list

Summary

In GenerateConstantOffsetsImpl, we may generate non canonical
Formula if BaseRegs of that Formula is updated and includes a
recurrent expr reg related with current loop while its ScaledReg
is not.

Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=47329

Diff Detail

Event Timeline

mdchen created this revision.Sep 1 2020, 7:15 AM

Herald added subscribers: llvm-commits, hiraditya. · View Herald TranscriptSep 1 2020, 7:15 AM

mdchen requested review of this revision.Sep 1 2020, 7:15 AM

Tests missing

Harbormaster completed remote builds in B70232: Diff 289160.Sep 1 2020, 7:45 AM

add a test case

LGTM, nitpicks below.

llvm/test/Transforms/LoopStrengthReduce/AArch64/pr47329.ll
1	Could you add a check that we generate something sensible? (Not crashing is not a good enough check :))
22	Please get rid of the implicit variables (%[0-9]+). (You can use `opt -instnamer` for that.)

This revision is now accepted and ready to land.Sep 2 2020, 12:01 PM

mdchen added inline comments.Sep 2 2020, 8:06 PM

llvm/test/Transforms/LoopStrengthReduce/AArch64/pr47329.ll
1	I agree it's not good enough. However, the IR generated with assertions turned off is no difference with the one generated with this fix patch and I can't come up with reasonable checks here. I'd appreciate it if you can give some guidance :)

Closed by commit rG78071fb52456: [LSR] Canonicalize a formula before insert it into the list (authored by wwei). · Explain WhySep 7 2020, 10:39 PM

This revision was automatically updated to reflect the committed changes.

wwei added a commit: rG78071fb52456: [LSR] Canonicalize a formula before insert it into the list.

Revision Contents

Path

Size

llvm/

lib/

Transforms/

Scalar/

LoopStrengthReduce.cpp

6 lines

test/

Transforms/

LoopStrengthReduce/

AArch64/

pr47329.ll

301 lines

Diff 289433

llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp

Show First 20 Lines • Show All 3,830 Lines • ▼ Show 20 Lines	void LSRInstance::GenerateConstantOffsetsImpl(
if (G->isZero() \|\| Imm == 0)		if (G->isZero() \|\| Imm == 0)
return;		return;
Formula F = Base;		Formula F = Base;
F.BaseOffset = (uint64_t)F.BaseOffset + Imm;		F.BaseOffset = (uint64_t)F.BaseOffset + Imm;
if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy, F))		if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy, F))
return;		return;
if (IsScaledReg)		if (IsScaledReg)
F.ScaledReg = G;		F.ScaledReg = G;
else		else {
F.BaseRegs[Idx] = G;		F.BaseRegs[Idx] = G;
		// We may generate non canonical Formula if G is a recurrent expr reg
		// related with current loop while F.ScaledReg is not.
		F.canonicalize(*L);
		}
(void)InsertFormula(LU, LUIdx, F);		(void)InsertFormula(LU, LUIdx, F);
}		}

/// GenerateConstantOffsets - Generate reuse formulae using symbolic offsets.		/// GenerateConstantOffsets - Generate reuse formulae using symbolic offsets.
void LSRInstance::GenerateConstantOffsets(LSRUse &LU, unsigned LUIdx,		void LSRInstance::GenerateConstantOffsets(LSRUse &LU, unsigned LUIdx,
Formula Base) {		Formula Base) {
// TODO: For now, just add the min and max offset, because it usually isn't		// TODO: For now, just add the min and max offset, because it usually isn't
// worthwhile looking at everything inbetween.		// worthwhile looking at everything inbetween.
▲ Show 20 Lines • Show All 1,997 Lines • Show Last 20 Lines

llvm/test/Transforms/LoopStrengthReduce/AArch64/pr47329.ll

This file was added.

				; RUN: opt < %s -loop-reduce
				qcolombetUnsubmitted Not Done Reply Inline Actions Could you add a check that we generate something sensible? (Not crashing is not a good enough check :)) qcolombet: Could you add a check that we generate something sensible? (Not crashing is not a good enough…
				mdchenAuthorUnsubmitted Done Reply Inline Actions I agree it's not good enough. However, the IR generated with assertions turned off is no difference with the one generated with this fix patch and I can't come up with reasonable checks here. I'd appreciate it if you can give some guidance :) mdchen: I agree it's not good enough. However, the IR generated with assertions turned off is no…

				target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
				target triple = "aarch64-unknown-linux-gnu"

				@d = internal unnamed_addr global i32** null, align 8

				define dso_local i32 @main() local_unnamed_addr {
				entry:
				%.pre.pre = load i32, i32* @d, align 8
				br label %for.body9

				for.body9: ; preds = %for.body9, %entry
				%0 = phi i32** [ %.pre.pre, %entry ], [ %incdec.ptr, %for.body9 ]
				%incdec.ptr = getelementptr inbounds i32, i32* %0, i64 -1
				br i1 undef, label %for.body9, label %for.inc

				for.inc: ; preds = %for.body9
				br label %for.body9.118

				for.body9.1: ; preds = %for.inc.547, %for.body9.1
				%1 = phi i32** [ %incdec.ptr.1, %for.body9.1 ], [ %incdec.ptr.542, %for.inc.547 ]
				qcolombetUnsubmitted Not Done Reply Inline Actions Please get rid of the implicit variables (%[0-9]+). (You can use `opt -instnamer` for that.) qcolombet: Please get rid of the implicit variables (%[0-9]+). (You can use `opt -instnamer` for that.)
				%incdec.ptr.1 = getelementptr inbounds i32, i32* %1, i64 -1
				br i1 undef, label %for.body9.1, label %for.inc.1

				for.inc.1: ; preds = %for.body9.1
				br label %for.body9.1.1

				for.body9.2: ; preds = %for.inc.1.5, %for.body9.2
				%2 = phi i32** [ %incdec.ptr.2, %for.body9.2 ], [ %incdec.ptr.1.5, %for.inc.1.5 ]
				%incdec.ptr.2 = getelementptr inbounds i32, i32* %2, i64 -1
				br i1 undef, label %for.body9.2, label %for.inc.2

				for.inc.2: ; preds = %for.body9.2
				br label %for.body9.2.1

				for.body9.3: ; preds = %for.inc.2.5, %for.body9.3
				%3 = phi i32** [ %incdec.ptr.3, %for.body9.3 ], [ %incdec.ptr.2.5, %for.inc.2.5 ]
				%incdec.ptr.3 = getelementptr inbounds i32, i32* %3, i64 -1
				br i1 undef, label %for.body9.3, label %for.inc.3

				for.inc.3: ; preds = %for.body9.3
				br label %for.body9.3.1

				for.body9.4: ; preds = %for.inc.3.5, %for.body9.4
				%4 = phi i32** [ %incdec.ptr.4, %for.body9.4 ], [ %incdec.ptr.3.5, %for.inc.3.5 ]
				%incdec.ptr.4 = getelementptr inbounds i32, i32* %4, i64 -1
				br i1 undef, label %for.body9.4, label %for.inc.4

				for.inc.4: ; preds = %for.body9.4
				br label %for.body9.4.1

				for.body9.5: ; preds = %for.inc.4.5, %for.body9.5
				%5 = phi i32** [ %incdec.ptr.5, %for.body9.5 ], [ %incdec.ptr.4.5, %for.inc.4.5 ]
				%incdec.ptr.5 = getelementptr inbounds i32, i32* %5, i64 -1
				br i1 undef, label %for.body9.5, label %for.inc.5

				for.inc.5: ; preds = %for.body9.5
				br label %for.body9.5.1

				for.body9.5.1: ; preds = %for.body9.5.1, %for.inc.5
				%6 = phi i32** [ %incdec.ptr.5.1, %for.body9.5.1 ], [ %incdec.ptr.5, %for.inc.5 ]
				%incdec.ptr.5.1 = getelementptr inbounds i32, i32* %6, i64 -1
				br i1 undef, label %for.body9.5.1, label %for.inc.5.1

				for.inc.5.1: ; preds = %for.body9.5.1
				br label %for.body9.5.2

				for.body9.5.2: ; preds = %for.body9.5.2, %for.inc.5.1
				%7 = phi i32** [ %incdec.ptr.5.2, %for.body9.5.2 ], [ %incdec.ptr.5.1, %for.inc.5.1 ]
				%incdec.ptr.5.2 = getelementptr inbounds i32, i32* %7, i64 -1
				br i1 undef, label %for.body9.5.2, label %for.inc.5.2

				for.inc.5.2: ; preds = %for.body9.5.2
				br label %for.body9.5.3

				for.body9.5.3: ; preds = %for.body9.5.3, %for.inc.5.2
				%8 = phi i32** [ %incdec.ptr.5.3, %for.body9.5.3 ], [ %incdec.ptr.5.2, %for.inc.5.2 ]
				%incdec.ptr.5.3 = getelementptr inbounds i32, i32* %8, i64 -1
				br i1 undef, label %for.body9.5.3, label %for.inc.5.3

				for.inc.5.3: ; preds = %for.body9.5.3
				br label %for.body9.5.4

				for.body9.5.4: ; preds = %for.body9.5.4, %for.inc.5.3
				%9 = phi i32** [ %incdec.ptr.5.4, %for.body9.5.4 ], [ %incdec.ptr.5.3, %for.inc.5.3 ]
				%incdec.ptr.5.4 = getelementptr inbounds i32, i32* %9, i64 -1
				br i1 undef, label %for.body9.5.4, label %for.inc.5.4

				for.inc.5.4: ; preds = %for.body9.5.4
				br label %for.body9.5.5

				for.body9.5.5: ; preds = %for.body9.5.5, %for.inc.5.4
				%10 = phi i32** [ undef, %for.body9.5.5 ], [ %incdec.ptr.5.4, %for.inc.5.4 ]
				%11 = bitcast i32** %10 to i64*
				%12 = load i64, i64* %11, align 8
				br label %for.body9.5.5

				for.body9.4.1: ; preds = %for.body9.4.1, %for.inc.4
				%13 = phi i32** [ %incdec.ptr.4.1, %for.body9.4.1 ], [ %incdec.ptr.4, %for.inc.4 ]
				%incdec.ptr.4.1 = getelementptr inbounds i32, i32* %13, i64 -1
				br i1 undef, label %for.body9.4.1, label %for.inc.4.1

				for.inc.4.1: ; preds = %for.body9.4.1
				br label %for.body9.4.2

				for.body9.4.2: ; preds = %for.body9.4.2, %for.inc.4.1
				%14 = phi i32** [ %incdec.ptr.4.2, %for.body9.4.2 ], [ %incdec.ptr.4.1, %for.inc.4.1 ]
				%incdec.ptr.4.2 = getelementptr inbounds i32, i32* %14, i64 -1
				br i1 undef, label %for.body9.4.2, label %for.inc.4.2

				for.inc.4.2: ; preds = %for.body9.4.2
				br label %for.body9.4.3

				for.body9.4.3: ; preds = %for.body9.4.3, %for.inc.4.2
				%15 = phi i32** [ %incdec.ptr.4.3, %for.body9.4.3 ], [ %incdec.ptr.4.2, %for.inc.4.2 ]
				%incdec.ptr.4.3 = getelementptr inbounds i32, i32* %15, i64 -1
				br i1 undef, label %for.body9.4.3, label %for.inc.4.3

				for.inc.4.3: ; preds = %for.body9.4.3
				br label %for.body9.4.4

				for.body9.4.4: ; preds = %for.body9.4.4, %for.inc.4.3
				%16 = phi i32** [ %incdec.ptr.4.4, %for.body9.4.4 ], [ %incdec.ptr.4.3, %for.inc.4.3 ]
				%incdec.ptr.4.4 = getelementptr inbounds i32, i32* %16, i64 -1
				br i1 undef, label %for.body9.4.4, label %for.inc.4.4

				for.inc.4.4: ; preds = %for.body9.4.4
				br label %for.body9.4.5

				for.body9.4.5: ; preds = %for.body9.4.5, %for.inc.4.4
				%17 = phi i32** [ %incdec.ptr.4.5, %for.body9.4.5 ], [ %incdec.ptr.4.4, %for.inc.4.4 ]
				%incdec.ptr.4.5 = getelementptr inbounds i32, i32* %17, i64 -1
				br i1 undef, label %for.body9.4.5, label %for.inc.4.5

				for.inc.4.5: ; preds = %for.body9.4.5
				br label %for.body9.5

				for.body9.3.1: ; preds = %for.body9.3.1, %for.inc.3
				%18 = phi i32** [ %incdec.ptr.3.1, %for.body9.3.1 ], [ %incdec.ptr.3, %for.inc.3 ]
				%incdec.ptr.3.1 = getelementptr inbounds i32, i32* %18, i64 -1
				br i1 undef, label %for.body9.3.1, label %for.inc.3.1

				for.inc.3.1: ; preds = %for.body9.3.1
				br label %for.body9.3.2

				for.body9.3.2: ; preds = %for.body9.3.2, %for.inc.3.1
				%19 = phi i32** [ %incdec.ptr.3.2, %for.body9.3.2 ], [ %incdec.ptr.3.1, %for.inc.3.1 ]
				%incdec.ptr.3.2 = getelementptr inbounds i32, i32* %19, i64 -1
				br i1 undef, label %for.body9.3.2, label %for.inc.3.2

				for.inc.3.2: ; preds = %for.body9.3.2
				br label %for.body9.3.3

				for.body9.3.3: ; preds = %for.body9.3.3, %for.inc.3.2
				%20 = phi i32** [ %incdec.ptr.3.3, %for.body9.3.3 ], [ %incdec.ptr.3.2, %for.inc.3.2 ]
				%incdec.ptr.3.3 = getelementptr inbounds i32, i32* %20, i64 -1
				br i1 undef, label %for.body9.3.3, label %for.inc.3.3

				for.inc.3.3: ; preds = %for.body9.3.3
				br label %for.body9.3.4

				for.body9.3.4: ; preds = %for.body9.3.4, %for.inc.3.3
				%21 = phi i32** [ %incdec.ptr.3.4, %for.body9.3.4 ], [ %incdec.ptr.3.3, %for.inc.3.3 ]
				%incdec.ptr.3.4 = getelementptr inbounds i32, i32* %21, i64 -1
				br i1 undef, label %for.body9.3.4, label %for.inc.3.4

				for.inc.3.4: ; preds = %for.body9.3.4
				br label %for.body9.3.5

				for.body9.3.5: ; preds = %for.body9.3.5, %for.inc.3.4
				%22 = phi i32** [ %incdec.ptr.3.5, %for.body9.3.5 ], [ %incdec.ptr.3.4, %for.inc.3.4 ]
				%incdec.ptr.3.5 = getelementptr inbounds i32, i32* %22, i64 -1
				br i1 undef, label %for.body9.3.5, label %for.inc.3.5

				for.inc.3.5: ; preds = %for.body9.3.5
				br label %for.body9.4

				for.body9.2.1: ; preds = %for.body9.2.1, %for.inc.2
				%23 = phi i32** [ %incdec.ptr.2.1, %for.body9.2.1 ], [ %incdec.ptr.2, %for.inc.2 ]
				%incdec.ptr.2.1 = getelementptr inbounds i32, i32* %23, i64 -1
				br i1 undef, label %for.body9.2.1, label %for.inc.2.1

				for.inc.2.1: ; preds = %for.body9.2.1
				br label %for.body9.2.2

				for.body9.2.2: ; preds = %for.body9.2.2, %for.inc.2.1
				%24 = phi i32** [ %incdec.ptr.2.2, %for.body9.2.2 ], [ %incdec.ptr.2.1, %for.inc.2.1 ]
				%incdec.ptr.2.2 = getelementptr inbounds i32, i32* %24, i64 -1
				br i1 undef, label %for.body9.2.2, label %for.inc.2.2

				for.inc.2.2: ; preds = %for.body9.2.2
				br label %for.body9.2.3

				for.body9.2.3: ; preds = %for.body9.2.3, %for.inc.2.2
				%25 = phi i32** [ %incdec.ptr.2.3, %for.body9.2.3 ], [ %incdec.ptr.2.2, %for.inc.2.2 ]
				%incdec.ptr.2.3 = getelementptr inbounds i32, i32* %25, i64 -1
				br i1 undef, label %for.body9.2.3, label %for.inc.2.3

				for.inc.2.3: ; preds = %for.body9.2.3
				br label %for.body9.2.4

				for.body9.2.4: ; preds = %for.body9.2.4, %for.inc.2.3
				%26 = phi i32** [ %incdec.ptr.2.4, %for.body9.2.4 ], [ %incdec.ptr.2.3, %for.inc.2.3 ]
				%incdec.ptr.2.4 = getelementptr inbounds i32, i32* %26, i64 -1
				br i1 undef, label %for.body9.2.4, label %for.inc.2.4

				for.inc.2.4: ; preds = %for.body9.2.4
				br label %for.body9.2.5

				for.body9.2.5: ; preds = %for.body9.2.5, %for.inc.2.4
				%27 = phi i32** [ %incdec.ptr.2.5, %for.body9.2.5 ], [ %incdec.ptr.2.4, %for.inc.2.4 ]
				%incdec.ptr.2.5 = getelementptr inbounds i32, i32* %27, i64 -1
				br i1 undef, label %for.body9.2.5, label %for.inc.2.5

				for.inc.2.5: ; preds = %for.body9.2.5
				br label %for.body9.3

				for.body9.1.1: ; preds = %for.body9.1.1, %for.inc.1
				%28 = phi i32** [ %incdec.ptr.1.1, %for.body9.1.1 ], [ %incdec.ptr.1, %for.inc.1 ]
				%incdec.ptr.1.1 = getelementptr inbounds i32, i32* %28, i64 -1
				br i1 undef, label %for.body9.1.1, label %for.inc.1.1

				for.inc.1.1: ; preds = %for.body9.1.1
				br label %for.body9.1.2

				for.body9.1.2: ; preds = %for.body9.1.2, %for.inc.1.1
				%29 = phi i32** [ %incdec.ptr.1.2, %for.body9.1.2 ], [ %incdec.ptr.1.1, %for.inc.1.1 ]
				%incdec.ptr.1.2 = getelementptr inbounds i32, i32* %29, i64 -1
				br i1 undef, label %for.body9.1.2, label %for.inc.1.2

				for.inc.1.2: ; preds = %for.body9.1.2
				br label %for.body9.1.3

				for.body9.1.3: ; preds = %for.body9.1.3, %for.inc.1.2
				%30 = phi i32** [ %incdec.ptr.1.3, %for.body9.1.3 ], [ %incdec.ptr.1.2, %for.inc.1.2 ]
				%incdec.ptr.1.3 = getelementptr inbounds i32, i32* %30, i64 -1
				br i1 undef, label %for.body9.1.3, label %for.inc.1.3

				for.inc.1.3: ; preds = %for.body9.1.3
				br label %for.body9.1.4

				for.body9.1.4: ; preds = %for.body9.1.4, %for.inc.1.3
				%31 = phi i32** [ %incdec.ptr.1.4, %for.body9.1.4 ], [ %incdec.ptr.1.3, %for.inc.1.3 ]
				%incdec.ptr.1.4 = getelementptr inbounds i32, i32* %31, i64 -1
				br i1 undef, label %for.body9.1.4, label %for.inc.1.4

				for.inc.1.4: ; preds = %for.body9.1.4
				br label %for.body9.1.5

				for.body9.1.5: ; preds = %for.body9.1.5, %for.inc.1.4
				%32 = phi i32** [ %incdec.ptr.1.5, %for.body9.1.5 ], [ %incdec.ptr.1.4, %for.inc.1.4 ]
				%incdec.ptr.1.5 = getelementptr inbounds i32, i32* %32, i64 -1
				br i1 undef, label %for.body9.1.5, label %for.inc.1.5

				for.inc.1.5: ; preds = %for.body9.1.5
				br label %for.body9.2

				for.body9.118: ; preds = %for.body9.118, %for.inc
				%33 = phi i32** [ %incdec.ptr, %for.inc ], [ %incdec.ptr.114, %for.body9.118 ]
				%incdec.ptr.114 = getelementptr inbounds i32, i32* %33, i64 -1
				br i1 undef, label %for.body9.118, label %for.inc.119

				for.inc.119: ; preds = %for.body9.118
				br label %for.body9.225

				for.body9.225: ; preds = %for.body9.225, %for.inc.119
				%34 = phi i32** [ %incdec.ptr.114, %for.inc.119 ], [ %incdec.ptr.221, %for.body9.225 ]
				%incdec.ptr.221 = getelementptr inbounds i32, i32* %34, i64 -1
				%35 = bitcast i32** %34 to i64*
				%36 = load i64, i64* %35, align 8
				br i1 undef, label %for.body9.225, label %for.inc.226

				for.inc.226: ; preds = %for.body9.225
				br label %for.body9.332

				for.body9.332: ; preds = %for.body9.332, %for.inc.226
				%37 = phi i32** [ %incdec.ptr.221, %for.inc.226 ], [ %incdec.ptr.328, %for.body9.332 ]
				%incdec.ptr.328 = getelementptr inbounds i32, i32* %37, i64 -1
				br i1 undef, label %for.body9.332, label %for.inc.333

				for.inc.333: ; preds = %for.body9.332
				br label %for.body9.439

				for.body9.439: ; preds = %for.body9.439, %for.inc.333
				%38 = phi i32** [ %incdec.ptr.328, %for.inc.333 ], [ %incdec.ptr.435, %for.body9.439 ]
				%incdec.ptr.435 = getelementptr inbounds i32, i32* %38, i64 -1
				br i1 undef, label %for.body9.439, label %for.inc.440

				for.inc.440: ; preds = %for.body9.439
				br label %for.body9.546

				for.body9.546: ; preds = %for.body9.546, %for.inc.440
				%39 = phi i32** [ %incdec.ptr.435, %for.inc.440 ], [ %incdec.ptr.542, %for.body9.546 ]
				%incdec.ptr.542 = getelementptr inbounds i32, i32* %39, i64 -1
				br i1 undef, label %for.body9.546, label %for.inc.547

				for.inc.547: ; preds = %for.body9.546
				br label %for.body9.1
				}