[profcheck] Option to inject distinct small weights #159644
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@llvm/pr-subscribers-llvm-transforms Author: Mircea Trofin (mtrofin) ChangesThere are cases where the easiest way to regression-test a profile change is to add The list of weights used is a bunch of primes, used as a circular buffer. Full diff: https://github.com/llvm/llvm-project/pull/159644.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Utils/ProfileVerify.cpp b/llvm/lib/Transforms/Utils/ProfileVerify.cpp
index faacd422c009c..6119a49514b59 100644
--- a/llvm/lib/Transforms/Utils/ProfileVerify.cpp
+++ b/llvm/lib/Transforms/Utils/ProfileVerify.cpp
@@ -28,6 +28,10 @@ static cl::opt<bool>
AnnotateSelect("profcheck-annotate-select", cl::init(true),
cl::desc("Also inject (if missing) and verify MD_prof for "
"`select` instructions"));
+static cl::opt<bool>
+ WeightsForTest("profcheck-weights-for-test", cl::init(false),
+ cl::desc("Generate weights with small values for tests."));
+
static cl::opt<uint32_t> SelectTrueWeight(
"profcheck-default-select-true-weight", cl::init(2U),
cl::desc("When annotating `select` instructions, this value will be used "
@@ -91,6 +95,7 @@ bool ProfileInjector::inject() {
if (F.getEntryCount(/*AllowSynthetic=*/true)->getCount() == 0)
return false;
bool Changed = false;
+ uint32_t WeightsForTestOffset = 0;
for (auto &BB : F) {
if (AnnotateSelect) {
for (auto &I : BB) {
@@ -103,38 +108,49 @@ bool ProfileInjector::inject() {
if (!Term || Term->getMetadata(LLVMContext::MD_prof))
continue;
SmallVector<BranchProbability> Probs;
- Probs.reserve(Term->getNumSuccessors());
- for (auto I = 0U, E = Term->getNumSuccessors(); I < E; ++I)
- Probs.emplace_back(BPI.getEdgeProbability(&BB, Term->getSuccessor(I)));
- assert(llvm::find_if(Probs,
- [](const BranchProbability &P) {
- return P.isUnknown();
- }) == Probs.end() &&
- "All branch probabilities should be valid");
- const auto *FirstZeroDenominator =
- find_if(Probs, [](const BranchProbability &P) {
- return P.getDenominator() == 0;
- });
- (void)FirstZeroDenominator;
- assert(FirstZeroDenominator == Probs.end());
- const auto *FirstNonZeroNumerator =
- find_if(Probs, [](const BranchProbability &P) { return !P.isZero(); });
- assert(FirstNonZeroNumerator != Probs.end());
- DynamicAPInt LCM(Probs[0].getDenominator());
- DynamicAPInt GCD(FirstNonZeroNumerator->getNumerator());
- for (const auto &Prob : drop_begin(Probs)) {
- if (!Prob.getNumerator())
- continue;
- LCM = llvm::lcm(LCM, DynamicAPInt(Prob.getDenominator()));
- GCD = llvm::gcd(GCD, DynamicAPInt(Prob.getNumerator()));
- }
SmallVector<uint32_t> Weights;
Weights.reserve(Term->getNumSuccessors());
- for (const auto &Prob : Probs) {
- DynamicAPInt W =
- (Prob.getNumerator() * LCM / GCD) / Prob.getDenominator();
- Weights.emplace_back(static_cast<uint32_t>((int64_t)W));
+ if (WeightsForTest) {
+ static const std::vector<uint32_t> Primes{3, 5, 7, 11, 13, 17, 19,
+ 23, 29, 31, 37, 41, 43, 47,
+ 53, 59, 61, 67, 71};
+ for (uint32_t I = 0, E = Term->getNumSuccessors(); I < E; ++I)
+ Weights.emplace_back(
+ Primes[(WeightsForTestOffset + I) % Primes.size()]);
+ ++WeightsForTestOffset;
+ } else {
+ Probs.reserve(Term->getNumSuccessors());
+ for (auto I = 0U, E = Term->getNumSuccessors(); I < E; ++I)
+ Probs.emplace_back(BPI.getEdgeProbability(&BB, Term->getSuccessor(I)));
+
+ assert(llvm::find_if(Probs,
+ [](const BranchProbability &P) {
+ return P.isUnknown();
+ }) == Probs.end() &&
+ "All branch probabilities should be valid");
+ const auto *FirstZeroDenominator =
+ find_if(Probs, [](const BranchProbability &P) {
+ return P.getDenominator() == 0;
+ });
+ (void)FirstZeroDenominator;
+ assert(FirstZeroDenominator == Probs.end());
+ const auto *FirstNonZeroNumerator = find_if(
+ Probs, [](const BranchProbability &P) { return !P.isZero(); });
+ assert(FirstNonZeroNumerator != Probs.end());
+ DynamicAPInt LCM(Probs[0].getDenominator());
+ DynamicAPInt GCD(FirstNonZeroNumerator->getNumerator());
+ for (const auto &Prob : drop_begin(Probs)) {
+ if (!Prob.getNumerator())
+ continue;
+ LCM = llvm::lcm(LCM, DynamicAPInt(Prob.getDenominator()));
+ GCD = llvm::gcd(GCD, DynamicAPInt(Prob.getNumerator()));
+ }
+ for (const auto &Prob : Probs) {
+ DynamicAPInt W =
+ (Prob.getNumerator() * LCM / GCD) / Prob.getDenominator();
+ Weights.emplace_back(static_cast<uint32_t>((int64_t)W));
+ }
}
setBranchWeights(*Term, Weights, /*IsExpected=*/false);
Changed = true;
diff --git a/llvm/test/Transforms/PGOProfile/profcheck-synthetic.ll b/llvm/test/Transforms/PGOProfile/profcheck-synthetic.ll
new file mode 100644
index 0000000000000..a3fd6b1f512a9
--- /dev/null
+++ b/llvm/test/Transforms/PGOProfile/profcheck-synthetic.ll
@@ -0,0 +1,73 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --version 6
+; RUN: opt -passes=prof-inject -profcheck-weights-for-test %s -S -o - | FileCheck %s --check-prefixes=TEST,CHECK
+; RUN: opt -passes=prof-inject %s -S -o - | FileCheck %s --check-prefixes=NORMAL,CHECK
+
+define void @foo(i32 %cond) {
+; TEST-LABEL: define void @foo(
+; TEST-SAME: i32 [[COND:%.*]]) !prof [[PROF0:![0-9]+]] {
+; TEST-NEXT: [[I:%.*]] = icmp eq i32 [[COND]], 0
+; TEST-NEXT: br i1 [[I]], label %[[A:.*]], label %[[B:.*]], !prof [[PROF1:![0-9]+]]
+; TEST: [[A]]:
+; TEST-NEXT: switch i32 [[COND]], label %[[DEFAULT:.*]] [
+; TEST-NEXT: i32 10, label %[[C:.*]]
+; TEST-NEXT: i32 20, label %[[D:.*]]
+; TEST-NEXT: ], !prof [[PROF2:![0-9]+]]
+; TEST: [[BB1:.*:]]
+; TEST-NEXT: br label %[[B]]
+; TEST: [[B]]:
+; TEST-NEXT: ret void
+; TEST: [[DEFAULT]]:
+; TEST-NEXT: ret void
+; TEST: [[C]]:
+; TEST-NEXT: ret void
+; TEST: [[D]]:
+; TEST-NEXT: ret void
+;
+; NORMAL-LABEL: define void @foo(
+; NORMAL-SAME: i32 [[COND:%.*]]) !prof [[PROF0:![0-9]+]] {
+; NORMAL-NEXT: [[I:%.*]] = icmp eq i32 [[COND]], 0
+; NORMAL-NEXT: br i1 [[I]], label %[[A:.*]], label %[[B:.*]], !prof [[PROF1:![0-9]+]]
+; NORMAL: [[A]]:
+; NORMAL-NEXT: switch i32 [[COND]], label %[[DEFAULT:.*]] [
+; NORMAL-NEXT: i32 10, label %[[C:.*]]
+; NORMAL-NEXT: i32 20, label %[[D:.*]]
+; NORMAL-NEXT: ], !prof [[PROF2:![0-9]+]]
+; NORMAL: [[BB1:.*:]]
+; NORMAL-NEXT: br label %[[B]]
+; NORMAL: [[B]]:
+; NORMAL-NEXT: ret void
+; NORMAL: [[DEFAULT]]:
+; NORMAL-NEXT: ret void
+; NORMAL: [[C]]:
+; NORMAL-NEXT: ret void
+; NORMAL: [[D]]:
+; NORMAL-NEXT: ret void
+;
+ %i = icmp eq i32 %cond, 0
+ br i1 %i, label %a, label %b
+a:
+ switch i32 %cond, label %default [
+ i32 10, label %c
+ i32 20, label %d
+ ]
+ br label %b
+b:
+ ret void
+default:
+ ret void
+c:
+ ret void
+d:
+ ret void
+}
+;.
+; TEST: [[PROF0]] = !{!"function_entry_count", i64 1000}
+; TEST: [[PROF1]] = !{!"branch_weights", i32 3, i32 5}
+; TEST: [[PROF2]] = !{!"branch_weights", i32 5, i32 7, i32 11}
+;.
+; NORMAL: [[PROF0]] = !{!"function_entry_count", i64 1000}
+; NORMAL: [[PROF1]] = !{!"branch_weights", i32 3, i32 5}
+; NORMAL: [[PROF2]] = !{!"branch_weights", i32 1, i32 1, i32 1}
+;.
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}
|
|
@llvm/pr-subscribers-pgo Author: Mircea Trofin (mtrofin) ChangesThere are cases where the easiest way to regression-test a profile change is to add The list of weights used is a bunch of primes, used as a circular buffer. Full diff: https://github.com/llvm/llvm-project/pull/159644.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Utils/ProfileVerify.cpp b/llvm/lib/Transforms/Utils/ProfileVerify.cpp
index faacd422c009c..6119a49514b59 100644
--- a/llvm/lib/Transforms/Utils/ProfileVerify.cpp
+++ b/llvm/lib/Transforms/Utils/ProfileVerify.cpp
@@ -28,6 +28,10 @@ static cl::opt<bool>
AnnotateSelect("profcheck-annotate-select", cl::init(true),
cl::desc("Also inject (if missing) and verify MD_prof for "
"`select` instructions"));
+static cl::opt<bool>
+ WeightsForTest("profcheck-weights-for-test", cl::init(false),
+ cl::desc("Generate weights with small values for tests."));
+
static cl::opt<uint32_t> SelectTrueWeight(
"profcheck-default-select-true-weight", cl::init(2U),
cl::desc("When annotating `select` instructions, this value will be used "
@@ -91,6 +95,7 @@ bool ProfileInjector::inject() {
if (F.getEntryCount(/*AllowSynthetic=*/true)->getCount() == 0)
return false;
bool Changed = false;
+ uint32_t WeightsForTestOffset = 0;
for (auto &BB : F) {
if (AnnotateSelect) {
for (auto &I : BB) {
@@ -103,38 +108,49 @@ bool ProfileInjector::inject() {
if (!Term || Term->getMetadata(LLVMContext::MD_prof))
continue;
SmallVector<BranchProbability> Probs;
- Probs.reserve(Term->getNumSuccessors());
- for (auto I = 0U, E = Term->getNumSuccessors(); I < E; ++I)
- Probs.emplace_back(BPI.getEdgeProbability(&BB, Term->getSuccessor(I)));
- assert(llvm::find_if(Probs,
- [](const BranchProbability &P) {
- return P.isUnknown();
- }) == Probs.end() &&
- "All branch probabilities should be valid");
- const auto *FirstZeroDenominator =
- find_if(Probs, [](const BranchProbability &P) {
- return P.getDenominator() == 0;
- });
- (void)FirstZeroDenominator;
- assert(FirstZeroDenominator == Probs.end());
- const auto *FirstNonZeroNumerator =
- find_if(Probs, [](const BranchProbability &P) { return !P.isZero(); });
- assert(FirstNonZeroNumerator != Probs.end());
- DynamicAPInt LCM(Probs[0].getDenominator());
- DynamicAPInt GCD(FirstNonZeroNumerator->getNumerator());
- for (const auto &Prob : drop_begin(Probs)) {
- if (!Prob.getNumerator())
- continue;
- LCM = llvm::lcm(LCM, DynamicAPInt(Prob.getDenominator()));
- GCD = llvm::gcd(GCD, DynamicAPInt(Prob.getNumerator()));
- }
SmallVector<uint32_t> Weights;
Weights.reserve(Term->getNumSuccessors());
- for (const auto &Prob : Probs) {
- DynamicAPInt W =
- (Prob.getNumerator() * LCM / GCD) / Prob.getDenominator();
- Weights.emplace_back(static_cast<uint32_t>((int64_t)W));
+ if (WeightsForTest) {
+ static const std::vector<uint32_t> Primes{3, 5, 7, 11, 13, 17, 19,
+ 23, 29, 31, 37, 41, 43, 47,
+ 53, 59, 61, 67, 71};
+ for (uint32_t I = 0, E = Term->getNumSuccessors(); I < E; ++I)
+ Weights.emplace_back(
+ Primes[(WeightsForTestOffset + I) % Primes.size()]);
+ ++WeightsForTestOffset;
+ } else {
+ Probs.reserve(Term->getNumSuccessors());
+ for (auto I = 0U, E = Term->getNumSuccessors(); I < E; ++I)
+ Probs.emplace_back(BPI.getEdgeProbability(&BB, Term->getSuccessor(I)));
+
+ assert(llvm::find_if(Probs,
+ [](const BranchProbability &P) {
+ return P.isUnknown();
+ }) == Probs.end() &&
+ "All branch probabilities should be valid");
+ const auto *FirstZeroDenominator =
+ find_if(Probs, [](const BranchProbability &P) {
+ return P.getDenominator() == 0;
+ });
+ (void)FirstZeroDenominator;
+ assert(FirstZeroDenominator == Probs.end());
+ const auto *FirstNonZeroNumerator = find_if(
+ Probs, [](const BranchProbability &P) { return !P.isZero(); });
+ assert(FirstNonZeroNumerator != Probs.end());
+ DynamicAPInt LCM(Probs[0].getDenominator());
+ DynamicAPInt GCD(FirstNonZeroNumerator->getNumerator());
+ for (const auto &Prob : drop_begin(Probs)) {
+ if (!Prob.getNumerator())
+ continue;
+ LCM = llvm::lcm(LCM, DynamicAPInt(Prob.getDenominator()));
+ GCD = llvm::gcd(GCD, DynamicAPInt(Prob.getNumerator()));
+ }
+ for (const auto &Prob : Probs) {
+ DynamicAPInt W =
+ (Prob.getNumerator() * LCM / GCD) / Prob.getDenominator();
+ Weights.emplace_back(static_cast<uint32_t>((int64_t)W));
+ }
}
setBranchWeights(*Term, Weights, /*IsExpected=*/false);
Changed = true;
diff --git a/llvm/test/Transforms/PGOProfile/profcheck-synthetic.ll b/llvm/test/Transforms/PGOProfile/profcheck-synthetic.ll
new file mode 100644
index 0000000000000..a3fd6b1f512a9
--- /dev/null
+++ b/llvm/test/Transforms/PGOProfile/profcheck-synthetic.ll
@@ -0,0 +1,73 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --version 6
+; RUN: opt -passes=prof-inject -profcheck-weights-for-test %s -S -o - | FileCheck %s --check-prefixes=TEST,CHECK
+; RUN: opt -passes=prof-inject %s -S -o - | FileCheck %s --check-prefixes=NORMAL,CHECK
+
+define void @foo(i32 %cond) {
+; TEST-LABEL: define void @foo(
+; TEST-SAME: i32 [[COND:%.*]]) !prof [[PROF0:![0-9]+]] {
+; TEST-NEXT: [[I:%.*]] = icmp eq i32 [[COND]], 0
+; TEST-NEXT: br i1 [[I]], label %[[A:.*]], label %[[B:.*]], !prof [[PROF1:![0-9]+]]
+; TEST: [[A]]:
+; TEST-NEXT: switch i32 [[COND]], label %[[DEFAULT:.*]] [
+; TEST-NEXT: i32 10, label %[[C:.*]]
+; TEST-NEXT: i32 20, label %[[D:.*]]
+; TEST-NEXT: ], !prof [[PROF2:![0-9]+]]
+; TEST: [[BB1:.*:]]
+; TEST-NEXT: br label %[[B]]
+; TEST: [[B]]:
+; TEST-NEXT: ret void
+; TEST: [[DEFAULT]]:
+; TEST-NEXT: ret void
+; TEST: [[C]]:
+; TEST-NEXT: ret void
+; TEST: [[D]]:
+; TEST-NEXT: ret void
+;
+; NORMAL-LABEL: define void @foo(
+; NORMAL-SAME: i32 [[COND:%.*]]) !prof [[PROF0:![0-9]+]] {
+; NORMAL-NEXT: [[I:%.*]] = icmp eq i32 [[COND]], 0
+; NORMAL-NEXT: br i1 [[I]], label %[[A:.*]], label %[[B:.*]], !prof [[PROF1:![0-9]+]]
+; NORMAL: [[A]]:
+; NORMAL-NEXT: switch i32 [[COND]], label %[[DEFAULT:.*]] [
+; NORMAL-NEXT: i32 10, label %[[C:.*]]
+; NORMAL-NEXT: i32 20, label %[[D:.*]]
+; NORMAL-NEXT: ], !prof [[PROF2:![0-9]+]]
+; NORMAL: [[BB1:.*:]]
+; NORMAL-NEXT: br label %[[B]]
+; NORMAL: [[B]]:
+; NORMAL-NEXT: ret void
+; NORMAL: [[DEFAULT]]:
+; NORMAL-NEXT: ret void
+; NORMAL: [[C]]:
+; NORMAL-NEXT: ret void
+; NORMAL: [[D]]:
+; NORMAL-NEXT: ret void
+;
+ %i = icmp eq i32 %cond, 0
+ br i1 %i, label %a, label %b
+a:
+ switch i32 %cond, label %default [
+ i32 10, label %c
+ i32 20, label %d
+ ]
+ br label %b
+b:
+ ret void
+default:
+ ret void
+c:
+ ret void
+d:
+ ret void
+}
+;.
+; TEST: [[PROF0]] = !{!"function_entry_count", i64 1000}
+; TEST: [[PROF1]] = !{!"branch_weights", i32 3, i32 5}
+; TEST: [[PROF2]] = !{!"branch_weights", i32 5, i32 7, i32 11}
+;.
+; NORMAL: [[PROF0]] = !{!"function_entry_count", i64 1000}
+; NORMAL: [[PROF1]] = !{!"branch_weights", i32 3, i32 5}
+; NORMAL: [[PROF2]] = !{!"branch_weights", i32 1, i32 1, i32 1}
+;.
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}
|
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There are cases where the easiest way to regression-test a profile change is to add `!prof` metadata, with small numbers as to simplify manual verification. To ensure coverage, this (the inserting) may become tedious. This patch makes `prof-inject` do that for us, if so opted in. The list of weights used is a bunch of primes, used as a circular buffer. Issue llvm#147390
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There are cases where the easiest way to regression-test a profile change is to add
!prof metadata, with small numbers as to simplify manual verification. To ensure coverage, this (the inserting) may become tedious. This patch makesprof-inject do that for us, if so opted in.The list of weights used is a bunch of primes, used as a circular buffer.
Issue #147390