[ConstantRange] Add support for shlWithNoWrap
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@llvm/pr-subscribers-llvm-transforms Author: Yingwei Zheng (dtcxzyw) ChangesThis patch adds initial support for Full diff: https://github.com/llvm/llvm-project/pull/100594.diff 4 Files Affected:
diff --git a/llvm/include/llvm/IR/ConstantRange.h b/llvm/include/llvm/IR/ConstantRange.h
index 86d0a6b35d748..d086c25390fd2 100644
--- a/llvm/include/llvm/IR/ConstantRange.h
+++ b/llvm/include/llvm/IR/ConstantRange.h
@@ -501,6 +501,14 @@ class [[nodiscard]] ConstantRange {
/// TODO: This isn't fully implemented yet.
ConstantRange shl(const ConstantRange &Other) const;
+ /// Return a new range representing the possible values resulting
+ /// from a left shift with wrap type \p NoWrapKind of a value in this
+ /// range and a value in \p Other.
+ /// If the result range is disjoint, the preferred range is determined by the
+ /// \p PreferredRangeType.
+ ConstantRange shlWithNoWrap(const ConstantRange &Other, unsigned NoWrapKind,
+ PreferredRangeType RangeType = Smallest) const;
+
/// Return a new range representing the possible values resulting from a
/// logical right shift of a value in this range and a value in \p Other.
ConstantRange lshr(const ConstantRange &Other) const;
diff --git a/llvm/lib/IR/ConstantRange.cpp b/llvm/lib/IR/ConstantRange.cpp
index 6068540cf08da..50b211a302e8f 100644
--- a/llvm/lib/IR/ConstantRange.cpp
+++ b/llvm/lib/IR/ConstantRange.cpp
@@ -988,6 +988,8 @@ ConstantRange ConstantRange::overflowingBinaryOp(Instruction::BinaryOps BinOp,
return subWithNoWrap(Other, NoWrapKind);
case Instruction::Mul:
return multiplyWithNoWrap(Other, NoWrapKind);
+ case Instruction::Shl:
+ return shlWithNoWrap(Other, NoWrapKind);
default:
// Don't know about this Overflowing Binary Operation.
// Conservatively fallback to plain binop handling.
@@ -1615,6 +1617,23 @@ ConstantRange::shl(const ConstantRange &Other) const {
return ConstantRange::getNonEmpty(std::move(Min), std::move(Max) + 1);
}
+ConstantRange ConstantRange::shlWithNoWrap(const ConstantRange &Other,
+ unsigned NoWrapKind,
+ PreferredRangeType RangeType) const {
+ if (isEmptySet() || Other.isEmptySet())
+ return getEmpty();
+
+ ConstantRange Result = shl(Other);
+
+ if (NoWrapKind & OverflowingBinaryOperator::NoSignedWrap)
+ Result = Result.intersectWith(sshl_sat(Other), RangeType);
+
+ if (NoWrapKind & OverflowingBinaryOperator::NoUnsignedWrap)
+ Result = Result.intersectWith(ushl_sat(Other), RangeType);
+
+ return Result;
+}
+
ConstantRange
ConstantRange::lshr(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
diff --git a/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll b/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll
index 88311219dee58..8b4dbc98425bf 100644
--- a/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll
+++ b/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll
@@ -86,7 +86,7 @@ define i8 @test4(i8 %a, i8 %b) {
; CHECK-NEXT: br i1 [[CMP]], label [[BB:%.*]], label [[EXIT:%.*]]
; CHECK: bb:
; CHECK-NEXT: [[SHL:%.*]] = shl nuw nsw i8 [[A:%.*]], [[B]]
-; CHECK-NEXT: ret i8 [[SHL]]
+; CHECK-NEXT: ret i8 -1
; CHECK: exit:
; CHECK-NEXT: ret i8 0
;
@@ -382,8 +382,7 @@ define i1 @nuw_range1(i8 %b) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[C:%.*]] = add nuw nsw i8 [[B:%.*]], 1
; CHECK-NEXT: [[SHL:%.*]] = shl nuw i8 [[C]], 2
-; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[SHL]], 0
-; CHECK-NEXT: ret i1 [[CMP]]
+; CHECK-NEXT: ret i1 false
;
entry:
%c = add nuw nsw i8 %b, 1
@@ -397,8 +396,7 @@ define i1 @nuw_range2(i8 %b) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[C:%.*]] = add nuw nsw i8 [[B:%.*]], 3
; CHECK-NEXT: [[SHL:%.*]] = shl nuw i8 [[C]], 2
-; CHECK-NEXT: [[CMP:%.*]] = icmp ult i8 [[SHL]], 2
-; CHECK-NEXT: ret i1 [[CMP]]
+; CHECK-NEXT: ret i1 false
;
entry:
%c = add nuw nsw i8 %b, 3
@@ -420,3 +418,59 @@ entry:
%cmp = icmp slt i8 %c, %shl
ret i1 %cmp
}
+
+define i64 @shl_nuw_nsw_test1(i32 %x) {
+; CHECK-LABEL: @shl_nuw_nsw_test1(
+; CHECK-NEXT: [[SHL1:%.*]] = shl nuw nsw i32 1, [[X:%.*]]
+; CHECK-NEXT: [[ADD1:%.*]] = add nsw i32 [[SHL1]], -1
+; CHECK-NEXT: [[EXT:%.*]] = zext nneg i32 [[ADD1]] to i64
+; CHECK-NEXT: [[SHL2:%.*]] = shl nuw nsw i64 [[EXT]], 2
+; CHECK-NEXT: [[ADD2:%.*]] = add nuw nsw i64 [[SHL2]], 39
+; CHECK-NEXT: [[LSHR:%.*]] = lshr i64 [[ADD2]], 3
+; CHECK-NEXT: ret i64 [[LSHR]]
+;
+ %shl1 = shl nuw nsw i32 1, %x
+ %add1 = add nsw i32 %shl1, -1
+ %ext = sext i32 %add1 to i64
+ %shl2 = shl nsw i64 %ext, 2
+ %add2 = add nsw i64 %shl2, 39
+ %lshr = lshr i64 %add2, 3
+ %and = and i64 %lshr, 4294967295
+ ret i64 %and
+}
+
+define i32 @shl_nuw_nsw_test2(i32 range(i32 -2147483248, 1) %x) {
+; CHECK-LABEL: @shl_nuw_nsw_test2(
+; CHECK-NEXT: [[SHL:%.*]] = shl nsw i32 [[X:%.*]], 1
+; CHECK-NEXT: ret i32 200
+;
+ %shl = shl nsw i32 %x, 1
+ %smax = call i32 @llvm.smax.i32(i32 %shl, i32 200)
+ ret i32 %smax
+}
+
+define i64 @shl_nuw_nsw_test3(i1 %cond, i64 range(i64 1, 0) %x, i64 range(i64 3, 0) %y) {
+; CHECK-LABEL: @shl_nuw_nsw_test3(
+; CHECK-NEXT: [[SHL:%.*]] = shl nuw i64 1, [[X:%.*]]
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[COND:%.*]], i64 [[Y:%.*]], i64 [[SHL]]
+; CHECK-NEXT: ret i64 [[SEL]]
+;
+ %shl = shl nuw i64 1, %x
+ %sel = select i1 %cond, i64 %y, i64 %shl
+ %umax = call i64 @llvm.umax.i64(i64 %sel, i64 2)
+ ret i64 %umax
+}
+
+define i1 @shl_nuw_nsw_test4(i32 %x, i32 range(i32 0, 32) %k) {
+; CHECK-LABEL: @shl_nuw_nsw_test4(
+; CHECK-NEXT: [[CONV:%.*]] = sext i32 [[X:%.*]] to i64
+; CHECK-NEXT: [[SH_PROM:%.*]] = zext nneg i32 [[K:%.*]] to i64
+; CHECK-NEXT: [[SHL:%.*]] = shl nsw i64 [[CONV]], [[SH_PROM]]
+; CHECK-NEXT: ret i1 false
+;
+ %conv = sext i32 %x to i64
+ %sh_prom = zext nneg i32 %k to i64
+ %shl = shl nsw i64 %conv, %sh_prom
+ %cmp = icmp eq i64 %shl, -9223372036854775808
+ ret i1 %cmp
+}
diff --git a/llvm/unittests/IR/ConstantRangeTest.cpp b/llvm/unittests/IR/ConstantRangeTest.cpp
index 7977a78a7d3ec..1705f3e6af977 100644
--- a/llvm/unittests/IR/ConstantRangeTest.cpp
+++ b/llvm/unittests/IR/ConstantRangeTest.cpp
@@ -1502,6 +1502,48 @@ TEST_F(ConstantRangeTest, Shl) {
});
}
+TEST_F(ConstantRangeTest, ShlWithNoWrap) {
+ using OBO = OverflowingBinaryOperator;
+ TestBinaryOpExhaustive(
+ [](const ConstantRange &CR1, const ConstantRange &CR2) {
+ return CR1.shlWithNoWrap(CR2, OBO::NoUnsignedWrap);
+ },
+ [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+ bool IsOverflow;
+ APInt Res = N1.ushl_ov(N2, IsOverflow);
+ if (IsOverflow)
+ return std::nullopt;
+ return Res;
+ },
+ PreferSmallest, CheckCorrectnessOnly);
+ TestBinaryOpExhaustive(
+ [](const ConstantRange &CR1, const ConstantRange &CR2) {
+ return CR1.shlWithNoWrap(CR2, OBO::NoSignedWrap);
+ },
+ [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+ bool IsOverflow;
+ APInt Res = N1.sshl_ov(N2, IsOverflow);
+ if (IsOverflow)
+ return std::nullopt;
+ return Res;
+ },
+ PreferSmallest, CheckCorrectnessOnly);
+ TestBinaryOpExhaustive(
+ [](const ConstantRange &CR1, const ConstantRange &CR2) {
+ return CR1.shlWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
+ },
+ [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+ bool IsOverflow1, IsOverflow2;
+ APInt Res1 = N1.ushl_ov(N2, IsOverflow1);
+ APInt Res2 = N1.sshl_ov(N2, IsOverflow2);
+ if (IsOverflow1 || IsOverflow2)
+ return std::nullopt;
+ assert(Res1 == Res2 && "Left shift results differ?");
+ return Res1;
+ },
+ PreferSmallest, CheckCorrectnessOnly);
+}
+
TEST_F(ConstantRangeTest, Lshr) {
EXPECT_EQ(Full.lshr(Full), Full);
EXPECT_EQ(Full.lshr(Empty), Empty);
|
|
@llvm/pr-subscribers-llvm-ir Author: Yingwei Zheng (dtcxzyw) ChangesThis patch adds initial support for Full diff: https://github.com/llvm/llvm-project/pull/100594.diff 4 Files Affected:
diff --git a/llvm/include/llvm/IR/ConstantRange.h b/llvm/include/llvm/IR/ConstantRange.h
index 86d0a6b35d748..d086c25390fd2 100644
--- a/llvm/include/llvm/IR/ConstantRange.h
+++ b/llvm/include/llvm/IR/ConstantRange.h
@@ -501,6 +501,14 @@ class [[nodiscard]] ConstantRange {
/// TODO: This isn't fully implemented yet.
ConstantRange shl(const ConstantRange &Other) const;
+ /// Return a new range representing the possible values resulting
+ /// from a left shift with wrap type \p NoWrapKind of a value in this
+ /// range and a value in \p Other.
+ /// If the result range is disjoint, the preferred range is determined by the
+ /// \p PreferredRangeType.
+ ConstantRange shlWithNoWrap(const ConstantRange &Other, unsigned NoWrapKind,
+ PreferredRangeType RangeType = Smallest) const;
+
/// Return a new range representing the possible values resulting from a
/// logical right shift of a value in this range and a value in \p Other.
ConstantRange lshr(const ConstantRange &Other) const;
diff --git a/llvm/lib/IR/ConstantRange.cpp b/llvm/lib/IR/ConstantRange.cpp
index 6068540cf08da..50b211a302e8f 100644
--- a/llvm/lib/IR/ConstantRange.cpp
+++ b/llvm/lib/IR/ConstantRange.cpp
@@ -988,6 +988,8 @@ ConstantRange ConstantRange::overflowingBinaryOp(Instruction::BinaryOps BinOp,
return subWithNoWrap(Other, NoWrapKind);
case Instruction::Mul:
return multiplyWithNoWrap(Other, NoWrapKind);
+ case Instruction::Shl:
+ return shlWithNoWrap(Other, NoWrapKind);
default:
// Don't know about this Overflowing Binary Operation.
// Conservatively fallback to plain binop handling.
@@ -1615,6 +1617,23 @@ ConstantRange::shl(const ConstantRange &Other) const {
return ConstantRange::getNonEmpty(std::move(Min), std::move(Max) + 1);
}
+ConstantRange ConstantRange::shlWithNoWrap(const ConstantRange &Other,
+ unsigned NoWrapKind,
+ PreferredRangeType RangeType) const {
+ if (isEmptySet() || Other.isEmptySet())
+ return getEmpty();
+
+ ConstantRange Result = shl(Other);
+
+ if (NoWrapKind & OverflowingBinaryOperator::NoSignedWrap)
+ Result = Result.intersectWith(sshl_sat(Other), RangeType);
+
+ if (NoWrapKind & OverflowingBinaryOperator::NoUnsignedWrap)
+ Result = Result.intersectWith(ushl_sat(Other), RangeType);
+
+ return Result;
+}
+
ConstantRange
ConstantRange::lshr(const ConstantRange &Other) const {
if (isEmptySet() || Other.isEmptySet())
diff --git a/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll b/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll
index 88311219dee58..8b4dbc98425bf 100644
--- a/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll
+++ b/llvm/test/Transforms/CorrelatedValuePropagation/shl.ll
@@ -86,7 +86,7 @@ define i8 @test4(i8 %a, i8 %b) {
; CHECK-NEXT: br i1 [[CMP]], label [[BB:%.*]], label [[EXIT:%.*]]
; CHECK: bb:
; CHECK-NEXT: [[SHL:%.*]] = shl nuw nsw i8 [[A:%.*]], [[B]]
-; CHECK-NEXT: ret i8 [[SHL]]
+; CHECK-NEXT: ret i8 -1
; CHECK: exit:
; CHECK-NEXT: ret i8 0
;
@@ -382,8 +382,7 @@ define i1 @nuw_range1(i8 %b) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[C:%.*]] = add nuw nsw i8 [[B:%.*]], 1
; CHECK-NEXT: [[SHL:%.*]] = shl nuw i8 [[C]], 2
-; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[SHL]], 0
-; CHECK-NEXT: ret i1 [[CMP]]
+; CHECK-NEXT: ret i1 false
;
entry:
%c = add nuw nsw i8 %b, 1
@@ -397,8 +396,7 @@ define i1 @nuw_range2(i8 %b) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[C:%.*]] = add nuw nsw i8 [[B:%.*]], 3
; CHECK-NEXT: [[SHL:%.*]] = shl nuw i8 [[C]], 2
-; CHECK-NEXT: [[CMP:%.*]] = icmp ult i8 [[SHL]], 2
-; CHECK-NEXT: ret i1 [[CMP]]
+; CHECK-NEXT: ret i1 false
;
entry:
%c = add nuw nsw i8 %b, 3
@@ -420,3 +418,59 @@ entry:
%cmp = icmp slt i8 %c, %shl
ret i1 %cmp
}
+
+define i64 @shl_nuw_nsw_test1(i32 %x) {
+; CHECK-LABEL: @shl_nuw_nsw_test1(
+; CHECK-NEXT: [[SHL1:%.*]] = shl nuw nsw i32 1, [[X:%.*]]
+; CHECK-NEXT: [[ADD1:%.*]] = add nsw i32 [[SHL1]], -1
+; CHECK-NEXT: [[EXT:%.*]] = zext nneg i32 [[ADD1]] to i64
+; CHECK-NEXT: [[SHL2:%.*]] = shl nuw nsw i64 [[EXT]], 2
+; CHECK-NEXT: [[ADD2:%.*]] = add nuw nsw i64 [[SHL2]], 39
+; CHECK-NEXT: [[LSHR:%.*]] = lshr i64 [[ADD2]], 3
+; CHECK-NEXT: ret i64 [[LSHR]]
+;
+ %shl1 = shl nuw nsw i32 1, %x
+ %add1 = add nsw i32 %shl1, -1
+ %ext = sext i32 %add1 to i64
+ %shl2 = shl nsw i64 %ext, 2
+ %add2 = add nsw i64 %shl2, 39
+ %lshr = lshr i64 %add2, 3
+ %and = and i64 %lshr, 4294967295
+ ret i64 %and
+}
+
+define i32 @shl_nuw_nsw_test2(i32 range(i32 -2147483248, 1) %x) {
+; CHECK-LABEL: @shl_nuw_nsw_test2(
+; CHECK-NEXT: [[SHL:%.*]] = shl nsw i32 [[X:%.*]], 1
+; CHECK-NEXT: ret i32 200
+;
+ %shl = shl nsw i32 %x, 1
+ %smax = call i32 @llvm.smax.i32(i32 %shl, i32 200)
+ ret i32 %smax
+}
+
+define i64 @shl_nuw_nsw_test3(i1 %cond, i64 range(i64 1, 0) %x, i64 range(i64 3, 0) %y) {
+; CHECK-LABEL: @shl_nuw_nsw_test3(
+; CHECK-NEXT: [[SHL:%.*]] = shl nuw i64 1, [[X:%.*]]
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[COND:%.*]], i64 [[Y:%.*]], i64 [[SHL]]
+; CHECK-NEXT: ret i64 [[SEL]]
+;
+ %shl = shl nuw i64 1, %x
+ %sel = select i1 %cond, i64 %y, i64 %shl
+ %umax = call i64 @llvm.umax.i64(i64 %sel, i64 2)
+ ret i64 %umax
+}
+
+define i1 @shl_nuw_nsw_test4(i32 %x, i32 range(i32 0, 32) %k) {
+; CHECK-LABEL: @shl_nuw_nsw_test4(
+; CHECK-NEXT: [[CONV:%.*]] = sext i32 [[X:%.*]] to i64
+; CHECK-NEXT: [[SH_PROM:%.*]] = zext nneg i32 [[K:%.*]] to i64
+; CHECK-NEXT: [[SHL:%.*]] = shl nsw i64 [[CONV]], [[SH_PROM]]
+; CHECK-NEXT: ret i1 false
+;
+ %conv = sext i32 %x to i64
+ %sh_prom = zext nneg i32 %k to i64
+ %shl = shl nsw i64 %conv, %sh_prom
+ %cmp = icmp eq i64 %shl, -9223372036854775808
+ ret i1 %cmp
+}
diff --git a/llvm/unittests/IR/ConstantRangeTest.cpp b/llvm/unittests/IR/ConstantRangeTest.cpp
index 7977a78a7d3ec..1705f3e6af977 100644
--- a/llvm/unittests/IR/ConstantRangeTest.cpp
+++ b/llvm/unittests/IR/ConstantRangeTest.cpp
@@ -1502,6 +1502,48 @@ TEST_F(ConstantRangeTest, Shl) {
});
}
+TEST_F(ConstantRangeTest, ShlWithNoWrap) {
+ using OBO = OverflowingBinaryOperator;
+ TestBinaryOpExhaustive(
+ [](const ConstantRange &CR1, const ConstantRange &CR2) {
+ return CR1.shlWithNoWrap(CR2, OBO::NoUnsignedWrap);
+ },
+ [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+ bool IsOverflow;
+ APInt Res = N1.ushl_ov(N2, IsOverflow);
+ if (IsOverflow)
+ return std::nullopt;
+ return Res;
+ },
+ PreferSmallest, CheckCorrectnessOnly);
+ TestBinaryOpExhaustive(
+ [](const ConstantRange &CR1, const ConstantRange &CR2) {
+ return CR1.shlWithNoWrap(CR2, OBO::NoSignedWrap);
+ },
+ [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+ bool IsOverflow;
+ APInt Res = N1.sshl_ov(N2, IsOverflow);
+ if (IsOverflow)
+ return std::nullopt;
+ return Res;
+ },
+ PreferSmallest, CheckCorrectnessOnly);
+ TestBinaryOpExhaustive(
+ [](const ConstantRange &CR1, const ConstantRange &CR2) {
+ return CR1.shlWithNoWrap(CR2, OBO::NoUnsignedWrap | OBO::NoSignedWrap);
+ },
+ [](const APInt &N1, const APInt &N2) -> std::optional<APInt> {
+ bool IsOverflow1, IsOverflow2;
+ APInt Res1 = N1.ushl_ov(N2, IsOverflow1);
+ APInt Res2 = N1.sshl_ov(N2, IsOverflow2);
+ if (IsOverflow1 || IsOverflow2)
+ return std::nullopt;
+ assert(Res1 == Res2 && "Left shift results differ?");
+ return Res1;
+ },
+ PreferSmallest, CheckCorrectnessOnly);
+}
+
TEST_F(ConstantRangeTest, Lshr) {
EXPECT_EQ(Full.lshr(Full), Full);
EXPECT_EQ(Full.lshr(Empty), Empty);
|
How come? Due to the suboptimal ranges found? |
Yeah, LLVM now produces |
banach-space
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that referenced
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Aug 7, 2024
This patch adds initial support for `ConstantRange:: shlWithNoWrap` to fold dtcxzyw/llvm-tools#22. However, this patch cannot fix the original issue. Improvements will be submitted in subsequent patches.
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This patch adds initial support for
ConstantRange:: shlWithNoWrapto fold dtcxzyw/llvm-tools#22. However, this patch cannot fix the original issue. Improvements forConstantRange::[u|s]shl_satwill be submitted in subsequent patches.