[llvm-branch-commits] [llvm] [KeyInstr] Add Atom Group waterline to LLVMContext (PR #133478)
Orlando Cazalet-Hyams via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Thu May 1 05:56:09 PDT 2025
https://github.com/OCHyams updated https://github.com/llvm/llvm-project/pull/133478
>From 511ee0a22ab388a8794dd4f487a23615eb4ad800 Mon Sep 17 00:00:00 2001
From: Orlando Cazalet-Hyams <orlando.hyams at sony.com>
Date: Tue, 18 Mar 2025 16:50:17 +0000
Subject: [PATCH 1/5] [KeyInstr] Add Atom Group waterline to LLVMContext
The waterline is managed through DILocation creation,
LLVMContext::incNextAtomGroup, and LLVMContext::updateAtomGroupWaterline.
Add unittest.
---
llvm/include/llvm/IR/LLVMContext.h | 8 +++++++
llvm/lib/IR/DebugInfoMetadata.cpp | 3 +++
llvm/lib/IR/LLVMContext.cpp | 8 +++++++
llvm/lib/IR/LLVMContextImpl.h | 10 ++++++++
llvm/unittests/IR/MetadataTest.cpp | 38 ++++++++++++++++++++++++++++++
5 files changed, 67 insertions(+)
diff --git a/llvm/include/llvm/IR/LLVMContext.h b/llvm/include/llvm/IR/LLVMContext.h
index bbd125fd38cf1..d3cdd31e0b12f 100644
--- a/llvm/include/llvm/IR/LLVMContext.h
+++ b/llvm/include/llvm/IR/LLVMContext.h
@@ -335,6 +335,14 @@ class LLVMContext {
StringRef getDefaultTargetFeatures();
void setDefaultTargetFeatures(StringRef Features);
+ /// Key Instructions: update the highest number atom group emitted for any
+ /// function.
+ void updateAtomGroupWaterline(uint64_t G);
+
+ /// Key Instructions: get the next free atom group number and increment
+ /// the global tracker.
+ uint64_t incNextAtomGroup();
+
private:
// Module needs access to the add/removeModule methods.
friend class Module;
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index f4f9fca38945c..aefda2f7be0b0 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -67,6 +67,9 @@ DILocation::DILocation(LLVMContext &C, StorageType Storage, unsigned Line,
#ifdef EXPERIMENTAL_KEY_INSTRUCTIONS
assert(AtomRank <= 7 && "AtomRank number should fit in 3 bits");
#endif
+ if (AtomRank)
+ C.updateAtomGroupWaterline(AtomGroup + 1);
+
assert((MDs.size() == 1 || MDs.size() == 2) &&
"Expected a scope and optional inlined-at");
// Set line and column.
diff --git a/llvm/lib/IR/LLVMContext.cpp b/llvm/lib/IR/LLVMContext.cpp
index 447e5d92e0b99..4781085b30431 100644
--- a/llvm/lib/IR/LLVMContext.cpp
+++ b/llvm/lib/IR/LLVMContext.cpp
@@ -377,3 +377,11 @@ StringRef LLVMContext::getDefaultTargetFeatures() {
void LLVMContext::setDefaultTargetFeatures(StringRef Features) {
pImpl->DefaultTargetFeatures = Features;
}
+
+void LLVMContext::updateAtomGroupWaterline(uint64_t V) {
+ pImpl->NextAtomGroup = std::max(pImpl->NextAtomGroup, V);
+}
+
+uint64_t LLVMContext::incNextAtomGroup() {
+ return pImpl->NextAtomGroup++;
+}
diff --git a/llvm/lib/IR/LLVMContextImpl.h b/llvm/lib/IR/LLVMContextImpl.h
index 99f0d8837de52..5a52d41834095 100644
--- a/llvm/lib/IR/LLVMContextImpl.h
+++ b/llvm/lib/IR/LLVMContextImpl.h
@@ -1832,6 +1832,16 @@ class LLVMContextImpl {
std::string DefaultTargetCPU;
std::string DefaultTargetFeatures;
+
+ /// The next available source atom group number. The front end is responsible
+ /// for assigning source atom numbers, but certain optimisations need to
+ /// assign new group numbers to a set of instructions. Most often code
+ /// duplication optimisations like loop unroll. Tracking a global maximum
+ /// value means we can know (cheaply) we're never using a group number that's
+ /// already used within this function.
+ ///
+ /// Start a 1 because 0 means the source location isn't part of an atom group.
+ uint64_t NextAtomGroup = 1;
};
} // end namespace llvm
diff --git a/llvm/unittests/IR/MetadataTest.cpp b/llvm/unittests/IR/MetadataTest.cpp
index 94cebb0406598..8a1c1f9d306c6 100644
--- a/llvm/unittests/IR/MetadataTest.cpp
+++ b/llvm/unittests/IR/MetadataTest.cpp
@@ -6,6 +6,7 @@
//
//===----------------------------------------------------------------------===//
+#include "../lib/IR/LLVMContextImpl.h"
#include "llvm/IR/Metadata.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
@@ -1366,6 +1367,43 @@ TEST_F(DILocationTest, discriminatorSpecialCases) {
EXPECT_EQ(std::nullopt, L4->cloneByMultiplyingDuplicationFactor(0x1000));
}
+TEST_F(DILocationTest, KeyInstructions) {
+ Context.pImpl->NextAtomGroup = 1;
+
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 1u);
+ DILocation *A1 = DILocation::get(Context, 1, 0, getSubprogram(), nullptr, false, 1, 2);
+ // The group is only applied to the DILocation if the build has opted into
+ // the additional DILocation fields needed for the feature.
+#ifdef EXPERIMENTAL_KEY_INSTRUCTIONS
+ EXPECT_EQ(A1->getAtomGroup(), 1u);
+ EXPECT_EQ(A1->getAtomRank(), 2u);
+#else
+ EXPECT_EQ(A1->getAtomGroup(), 0u);
+ EXPECT_EQ(A1->getAtomRank(), 0u);
+#endif
+
+ // Group number 1 has been "used" so next available is 2.
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 2u);
+
+ // Set a group number higher than current + 1, then check the waterline.
+ DILocation::get(Context, 2, 0, getSubprogram(), nullptr, false, 5, 1);
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 6u);
+
+ // The waterline should be unchanged (group <= next).
+ DILocation::get(Context, 3, 0, getSubprogram(), nullptr, false, 4, 1);
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 6u);
+ DILocation::get(Context, 3, 0, getSubprogram(), nullptr, false, 5, 1);
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 6u);
+
+ // Check the waterline gets incremented by 1.
+ EXPECT_EQ(Context.incNextAtomGroup(), 6u);
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 7u);
+
+ Context.updateAtomGroupWaterline(8);
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 8u);
+ Context.updateAtomGroupWaterline(7);
+ EXPECT_EQ(Context.pImpl->NextAtomGroup, 8u);
+}
typedef MetadataTest GenericDINodeTest;
>From 72efd59c62fa6dded259b593ce23f94f7867e3a9 Mon Sep 17 00:00:00 2001
From: Orlando Cazalet-Hyams <orlando.hyams at sony.com>
Date: Thu, 1 May 2025 13:19:36 +0100
Subject: [PATCH 2/5] clang-format
---
llvm/lib/IR/LLVMContext.cpp | 4 +---
llvm/unittests/IR/MetadataTest.cpp | 5 +++--
2 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/llvm/lib/IR/LLVMContext.cpp b/llvm/lib/IR/LLVMContext.cpp
index 4781085b30431..5a11c28671409 100644
--- a/llvm/lib/IR/LLVMContext.cpp
+++ b/llvm/lib/IR/LLVMContext.cpp
@@ -382,6 +382,4 @@ void LLVMContext::updateAtomGroupWaterline(uint64_t V) {
pImpl->NextAtomGroup = std::max(pImpl->NextAtomGroup, V);
}
-uint64_t LLVMContext::incNextAtomGroup() {
- return pImpl->NextAtomGroup++;
-}
+uint64_t LLVMContext::incNextAtomGroup() { return pImpl->NextAtomGroup++; }
diff --git a/llvm/unittests/IR/MetadataTest.cpp b/llvm/unittests/IR/MetadataTest.cpp
index 8a1c1f9d306c6..a94a5aaf5f10b 100644
--- a/llvm/unittests/IR/MetadataTest.cpp
+++ b/llvm/unittests/IR/MetadataTest.cpp
@@ -6,8 +6,8 @@
//
//===----------------------------------------------------------------------===//
-#include "../lib/IR/LLVMContextImpl.h"
#include "llvm/IR/Metadata.h"
+#include "../lib/IR/LLVMContextImpl.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/Constants.h"
@@ -1371,7 +1371,8 @@ TEST_F(DILocationTest, KeyInstructions) {
Context.pImpl->NextAtomGroup = 1;
EXPECT_EQ(Context.pImpl->NextAtomGroup, 1u);
- DILocation *A1 = DILocation::get(Context, 1, 0, getSubprogram(), nullptr, false, 1, 2);
+ DILocation *A1 =
+ DILocation::get(Context, 1, 0, getSubprogram(), nullptr, false, 1, 2);
// The group is only applied to the DILocation if the build has opted into
// the additional DILocation fields needed for the feature.
#ifdef EXPERIMENTAL_KEY_INSTRUCTIONS
>From b0fd78a79209fa7a62a8c1922d00b672457db6a2 Mon Sep 17 00:00:00 2001
From: Orlando Cazalet-Hyams <orlando.hyams at sony.com>
Date: Thu, 1 May 2025 13:40:03 +0100
Subject: [PATCH 3/5] rename functions
---
llvm/include/llvm/IR/LLVMContext.h | 4 ++--
llvm/lib/IR/DebugInfoMetadata.cpp | 2 +-
llvm/lib/IR/LLVMContext.cpp | 6 ++++--
3 files changed, 7 insertions(+), 5 deletions(-)
diff --git a/llvm/include/llvm/IR/LLVMContext.h b/llvm/include/llvm/IR/LLVMContext.h
index d3cdd31e0b12f..6dde7a968b570 100644
--- a/llvm/include/llvm/IR/LLVMContext.h
+++ b/llvm/include/llvm/IR/LLVMContext.h
@@ -337,11 +337,11 @@ class LLVMContext {
/// Key Instructions: update the highest number atom group emitted for any
/// function.
- void updateAtomGroupWaterline(uint64_t G);
+ void updateDILocationAtomGroupWaterline(uint64_t G);
/// Key Instructions: get the next free atom group number and increment
/// the global tracker.
- uint64_t incNextAtomGroup();
+ uint64_t incNextDILocationAtomGroup();
private:
// Module needs access to the add/removeModule methods.
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index aefda2f7be0b0..a34093084dc35 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -68,7 +68,7 @@ DILocation::DILocation(LLVMContext &C, StorageType Storage, unsigned Line,
assert(AtomRank <= 7 && "AtomRank number should fit in 3 bits");
#endif
if (AtomRank)
- C.updateAtomGroupWaterline(AtomGroup + 1);
+ C.updateDILocationAtomGroupWaterline(AtomGroup + 1);
assert((MDs.size() == 1 || MDs.size() == 2) &&
"Expected a scope and optional inlined-at");
diff --git a/llvm/lib/IR/LLVMContext.cpp b/llvm/lib/IR/LLVMContext.cpp
index 5a11c28671409..57532cd491dd6 100644
--- a/llvm/lib/IR/LLVMContext.cpp
+++ b/llvm/lib/IR/LLVMContext.cpp
@@ -378,8 +378,10 @@ void LLVMContext::setDefaultTargetFeatures(StringRef Features) {
pImpl->DefaultTargetFeatures = Features;
}
-void LLVMContext::updateAtomGroupWaterline(uint64_t V) {
+void LLVMContext::updateDILocationAtomGroupWaterline(uint64_t V) {
pImpl->NextAtomGroup = std::max(pImpl->NextAtomGroup, V);
}
-uint64_t LLVMContext::incNextAtomGroup() { return pImpl->NextAtomGroup++; }
+uint64_t LLVMContext::incNextDILocationAtomGroup() {
+ return pImpl->NextAtomGroup++;
+}
>From f01e83a1fe20295002a272d67d60116ead4e076a Mon Sep 17 00:00:00 2001
From: Orlando Cazalet-Hyams <orlando.hyams at sony.com>
Date: Thu, 1 May 2025 13:41:48 +0100
Subject: [PATCH 4/5] fix my fixme comment
---
llvm/lib/IR/DebugInfoMetadata.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index a34093084dc35..1a14e416dddd0 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -67,7 +67,7 @@ DILocation::DILocation(LLVMContext &C, StorageType Storage, unsigned Line,
#ifdef EXPERIMENTAL_KEY_INSTRUCTIONS
assert(AtomRank <= 7 && "AtomRank number should fit in 3 bits");
#endif
- if (AtomRank)
+ if (AtomGroup)
C.updateDILocationAtomGroupWaterline(AtomGroup + 1);
assert((MDs.size() == 1 || MDs.size() == 2) &&
>From 9c1e61e5e01a455aceba2581bc440ae072286491 Mon Sep 17 00:00:00 2001
From: Orlando Cazalet-Hyams <orlando.hyams at sony.com>
Date: Thu, 1 May 2025 13:46:57 +0100
Subject: [PATCH 5/5] simplify comment
---
llvm/unittests/IR/MetadataTest.cpp | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/llvm/unittests/IR/MetadataTest.cpp b/llvm/unittests/IR/MetadataTest.cpp
index a94a5aaf5f10b..90e38ac7004dc 100644
--- a/llvm/unittests/IR/MetadataTest.cpp
+++ b/llvm/unittests/IR/MetadataTest.cpp
@@ -1373,8 +1373,8 @@ TEST_F(DILocationTest, KeyInstructions) {
EXPECT_EQ(Context.pImpl->NextAtomGroup, 1u);
DILocation *A1 =
DILocation::get(Context, 1, 0, getSubprogram(), nullptr, false, 1, 2);
- // The group is only applied to the DILocation if the build has opted into
- // the additional DILocation fields needed for the feature.
+ // The group is only applied to the DILocation if we've built LLVM with
+ // EXPERIMENTAL_KEY_INSTRUCTIONS.
#ifdef EXPERIMENTAL_KEY_INSTRUCTIONS
EXPECT_EQ(A1->getAtomGroup(), 1u);
EXPECT_EQ(A1->getAtomRank(), 2u);
More information about the llvm-branch-commits
mailing list