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Differential D119584

[ConstraintElimination] Support add with precondition.
AbandonedPublic

Authored by markdewing on Feb 11 2022, 1:15 PM.

Details

Reviewers
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Summary

If we can prove that an addition without wrap flags won't wrap, decompse
the operation.

Issue #48253

Diff Detail

Unit TestsFailed

TimeTest
60,080 msx64 debian > AddressSanitizer-x86_64-linux.TestCases::scariness_score_test.cpp
60,120 msx64 debian > Clang.CodeGen/RISCV/rvv-intrinsics::vloxseg.c
60,190 msx64 debian > Clang.CodeGen/RISCV/rvv-intrinsics::vluxseg.c
60,200 msx64 debian > Clang.CodeGen/RISCV/rvv-intrinsics-overloaded::vloxseg.c
60,100 msx64 debian > Clang.CodeGen/RISCV/rvv-intrinsics-overloaded::vluxseg.c

Event Timeline

markdewing created this revision.Feb 11 2022, 1:15 PM
Herald added a subscriber: hiraditya. · View Herald TranscriptFeb 11 2022, 1:15 PM
markdewing requested review of this revision.Feb 11 2022, 1:15 PM
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Herald added a subscriber: llvm-commits. · View Herald Transcript
markdewing abandoned this revision.Feb 11 2022, 1:18 PM
Harbormaster completed remote builds in B149087: Diff 408026.Feb 11 2022, 3:01 PM

Revision Contents

PathSize
llvm/
lib/
Transforms/
Scalar/
6 lines
test/
Transforms/
ConstraintElimination/
8 lines

Diff 408026

llvm/lib/Transforms/Scalar/ConstraintElimination.cpp

//===-- ConstraintElimination.cpp - Eliminate conds using constraints. ----===// //===-- ConstraintElimination.cpp - Eliminate conds using constraints. ----===//
Lint: Lint
Inline Actions

clang-format not found in user’s local PATH; not linting file.

Lint: Lint: clang-format not found in user’s local PATH; not linting file.
// //
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information. // See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// //
//===----------------------------------------------------------------------===// //===----------------------------------------------------------------------===//
// //
▲ Show 20 Lines • Show All 215 Lines • ▼ Show 20 Linesdecompose(Value *V, SmallVector<PreconditionTy, 4> &Preconditions,
Value *Op0; Value *Op0;
if (match(V, m_ZExt(m_Value(Op0)))) if (match(V, m_ZExt(m_Value(Op0))))
V = Op0; V = Op0;
Value *Op1; Value *Op1;
ConstantInt *CI; ConstantInt *CI;
if (match(V, m_NUWAdd(m_Value(Op0), m_ConstantInt(CI)))) if (match(V, m_NUWAdd(m_Value(Op0), m_ConstantInt(CI))))
return {{CI->getSExtValue(), nullptr}, {1, Op0}}; return {{CI->getSExtValue(), nullptr}, {1, Op0}};
if (match(V, m_Add(m_Value(Op0), m_ConstantInt(CI))) && CI->isNegative()) {
Preconditions.emplace_back(
CmpInst::ICMP_UGE, Op0,
ConstantInt::get(Op0->getType(), CI->getSExtValue() * -1));
return {{CI->getSExtValue(), nullptr}, {1, Op0}};
}
if (match(V, m_NUWAdd(m_Value(Op0), m_Value(Op1)))) if (match(V, m_NUWAdd(m_Value(Op0), m_Value(Op1))))
return {{0, nullptr}, {1, Op0}, {1, Op1}}; return {{0, nullptr}, {1, Op0}, {1, Op1}};
if (match(V, m_NUWSub(m_Value(Op0), m_ConstantInt(CI)))) if (match(V, m_NUWSub(m_Value(Op0), m_ConstantInt(CI))))
return {{-1 * CI->getSExtValue(), nullptr}, {1, Op0}}; return {{-1 * CI->getSExtValue(), nullptr}, {1, Op0}};
if (match(V, m_NUWSub(m_Value(Op0), m_Value(Op1)))) if (match(V, m_NUWSub(m_Value(Op0), m_Value(Op1))))
return {{0, nullptr}, {1, Op0}, {-1, Op1}}; return {{0, nullptr}, {1, Op0}, {-1, Op1}};
▲ Show 20 Lines • Show All 464 Lines • Show Last 20 Lines

llvm/test/Transforms/ConstraintElimination/wrapping-math.ll

Show All 16 Lines
define i1 @wrapping_add_known_1(i8 %a) { define i1 @wrapping_add_known_1(i8 %a) {
; CHECK-LABEL: @wrapping_add_known_1( ; CHECK-LABEL: @wrapping_add_known_1(
; CHECK-NEXT: entry: ; CHECK-NEXT: entry:
; CHECK-NEXT: [[PRE:%.*]] = icmp eq i8 [[A:%.*]], 1 ; CHECK-NEXT: [[PRE:%.*]] = icmp eq i8 [[A:%.*]], 1
; CHECK-NEXT: br i1 [[PRE]], label [[THEN:%.*]], label [[ELSE:%.*]] ; CHECK-NEXT: br i1 [[PRE]], label [[THEN:%.*]], label [[ELSE:%.*]]
; CHECK: then: ; CHECK: then:
; CHECK-NEXT: [[SUB_1:%.*]] = add i8 [[A]], -1 ; CHECK-NEXT: [[SUB_1:%.*]] = add i8 [[A]], -1
; CHECK-NEXT: [[C_1:%.*]] = icmp eq i8 [[SUB_1]], 0 ; CHECK-NEXT: [[C_1:%.*]] = icmp eq i8 [[SUB_1]], 0
; CHECK-NEXT: ret i1 [[C_1]] ; CHECK-NEXT: ret i1 true
; CHECK: else: ; CHECK: else:
; CHECK-NEXT: [[SUB_2:%.*]] = add i8 [[A]], -1 ; CHECK-NEXT: [[SUB_2:%.*]] = add i8 [[A]], -1
; CHECK-NEXT: [[C_2:%.*]] = icmp eq i8 [[SUB_2]], 0 ; CHECK-NEXT: [[C_2:%.*]] = icmp eq i8 [[SUB_2]], 0
; CHECK-NEXT: ret i1 [[C_2]] ; CHECK-NEXT: ret i1 [[C_2]]
; ;
entry: entry:
%pre = icmp eq i8 %a, 1 %pre = icmp eq i8 %a, 1
br i1 %pre, label %then, label %else br i1 %pre, label %then, label %else
▲ Show 20 Lines • Show All 46 Lines • ▼ Show 20 Lines
; CHECK-NEXT: [[CMP_2:%.*]] = icmp eq i8 [[B]], 0 ; CHECK-NEXT: [[CMP_2:%.*]] = icmp eq i8 [[B]], 0
; CHECK-NEXT: [[OR:%.*]] = or i1 [[CMP_1]], [[CMP_2]] ; CHECK-NEXT: [[OR:%.*]] = or i1 [[CMP_1]], [[CMP_2]]
; CHECK-NEXT: br i1 [[OR]], label [[EXIT_1:%.*]], label [[IF_END:%.*]] ; CHECK-NEXT: br i1 [[OR]], label [[EXIT_1:%.*]], label [[IF_END:%.*]]
; CHECK: if.end: ; CHECK: if.end:
; CHECK-NEXT: [[SUB_1:%.*]] = add i8 [[B]], -1 ; CHECK-NEXT: [[SUB_1:%.*]] = add i8 [[B]], -1
; CHECK-NEXT: [[T_1:%.*]] = icmp ult i8 [[SUB_1]], [[A]] ; CHECK-NEXT: [[T_1:%.*]] = icmp ult i8 [[SUB_1]], [[A]]
; CHECK-NEXT: [[SUB_2:%.*]] = add i8 [[B]], -2 ; CHECK-NEXT: [[SUB_2:%.*]] = add i8 [[B]], -2
; CHECK-NEXT: [[C_2:%.*]] = icmp ult i8 [[SUB_2]], [[A]] ; CHECK-NEXT: [[C_2:%.*]] = icmp ult i8 [[SUB_2]], [[A]]
; CHECK-NEXT: [[XOR_1:%.*]] = xor i1 [[T_1]], [[C_2]] ; CHECK-NEXT: [[XOR_1:%.*]] = xor i1 true, [[C_2]]
; CHECK-NEXT: ret i1 [[XOR_1]] ; CHECK-NEXT: ret i1 [[XOR_1]]
; CHECK: exit.1: ; CHECK: exit.1:
; CHECK-NEXT: [[SUB_3:%.*]] = add i8 [[B]], -1 ; CHECK-NEXT: [[SUB_3:%.*]] = add i8 [[B]], -1
; CHECK-NEXT: [[C_3:%.*]] = icmp ult i8 [[SUB_3]], [[A]] ; CHECK-NEXT: [[C_3:%.*]] = icmp ult i8 [[SUB_3]], [[A]]
; CHECK-NEXT: [[SUB_4:%.*]] = add i8 [[B]], -2 ; CHECK-NEXT: [[SUB_4:%.*]] = add i8 [[B]], -2
; CHECK-NEXT: [[C_4:%.*]] = icmp ult i8 [[SUB_4]], [[A]] ; CHECK-NEXT: [[C_4:%.*]] = icmp ult i8 [[SUB_4]], [[A]]
; CHECK-NEXT: [[XOR_2:%.*]] = xor i1 [[C_3]], [[C_4]] ; CHECK-NEXT: [[XOR_2:%.*]] = xor i1 [[C_3]], [[C_4]]
; CHECK-NEXT: ret i1 [[XOR_2]] ; CHECK-NEXT: ret i1 [[XOR_2]]
Show All 31 Lines
; CHECK-NEXT: [[SUB_2:%.*]] = add i8 [[A]], -2 ; CHECK-NEXT: [[SUB_2:%.*]] = add i8 [[A]], -2
; CHECK-NEXT: [[SUB_3:%.*]] = add i8 [[A]], -20 ; CHECK-NEXT: [[SUB_3:%.*]] = add i8 [[A]], -20
; CHECK-NEXT: [[SUB_4:%.*]] = add i8 [[A]], 21 ; CHECK-NEXT: [[SUB_4:%.*]] = add i8 [[A]], 21
; CHECK-NEXT: [[ADD_1:%.*]] = add i8 [[A]], 1 ; CHECK-NEXT: [[ADD_1:%.*]] = add i8 [[A]], 1
; CHECK-NEXT: br i1 [[AND]], label [[IF_END:%.*]], label [[EXIT_1:%.*]] ; CHECK-NEXT: br i1 [[AND]], label [[IF_END:%.*]], label [[EXIT_1:%.*]]
; CHECK: if.end: ; CHECK: if.end:
; CHECK-NEXT: [[T_1:%.*]] = icmp ult i8 [[SUB_1]], [[B]] ; CHECK-NEXT: [[T_1:%.*]] = icmp ult i8 [[SUB_1]], [[B]]
; CHECK-NEXT: [[T_2:%.*]] = icmp ult i8 [[SUB_2]], [[B]] ; CHECK-NEXT: [[T_2:%.*]] = icmp ult i8 [[SUB_2]], [[B]]
; CHECK-NEXT: [[XOR_1:%.*]] = xor i1 [[T_1]], [[T_2]] ; CHECK-NEXT: [[XOR_1:%.*]] = xor i1 true, true
; CHECK-NEXT: [[T_3:%.*]] = icmp ult i8 [[SUB_3]], [[B]] ; CHECK-NEXT: [[T_3:%.*]] = icmp ult i8 [[SUB_3]], [[B]]
; CHECK-NEXT: [[XOR_2:%.*]] = xor i1 [[XOR_1]], [[T_3]] ; CHECK-NEXT: [[XOR_2:%.*]] = xor i1 [[XOR_1]], true
; CHECK-NEXT: [[C_1:%.*]] = icmp ult i8 [[SUB_4]], [[B]] ; CHECK-NEXT: [[C_1:%.*]] = icmp ult i8 [[SUB_4]], [[B]]
; CHECK-NEXT: [[XOR_3:%.*]] = xor i1 [[XOR_2]], [[C_1]] ; CHECK-NEXT: [[XOR_3:%.*]] = xor i1 [[XOR_2]], [[C_1]]
; CHECK-NEXT: [[C_2:%.*]] = icmp ult i8 [[ADD_1]], [[B]] ; CHECK-NEXT: [[C_2:%.*]] = icmp ult i8 [[ADD_1]], [[B]]
; CHECK-NEXT: [[XOR_4:%.*]] = xor i1 [[XOR_3]], [[C_2]] ; CHECK-NEXT: [[XOR_4:%.*]] = xor i1 [[XOR_3]], [[C_2]]
; CHECK-NEXT: ret i1 [[XOR_4]] ; CHECK-NEXT: ret i1 [[XOR_4]]
; CHECK: exit.1: ; CHECK: exit.1:
; CHECK-NEXT: [[C_3:%.*]] = icmp ult i8 [[SUB_1]], [[B]] ; CHECK-NEXT: [[C_3:%.*]] = icmp ult i8 [[SUB_1]], [[B]]
; CHECK-NEXT: [[C_4:%.*]] = icmp ult i8 [[SUB_2]], [[B]] ; CHECK-NEXT: [[C_4:%.*]] = icmp ult i8 [[SUB_2]], [[B]]
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