[clang] [TBAA] Emit int TBAA metadata on FP math libcalls (PR #96025)
via cfe-commits
cfe-commits at lists.llvm.org
Tue Jun 25 23:17:08 PDT 2024
https://github.com/vfdff updated https://github.com/llvm/llvm-project/pull/96025
>From ed6292fd0e9119322c39e5f37e2225c76e324101 Mon Sep 17 00:00:00 2001
From: zhongyunde 00443407 <zhongyunde at huawei.com>
Date: Tue, 18 Jun 2024 09:21:07 -0400
Subject: [PATCH 1/5] [TBAA] Emit int TBAA metadata on FP math libcalls
Base on the discussion https://discourse.llvm.org/t/fp-can-we-add-pure-attribute-for-math-library-functions-default/79459,
math libcalls set errno, so it should emit "int" TBAA metadata on FP libcalls
to solve the alias issue.
Fix https://github.com/llvm/llvm-project/issues/86635
---
clang/lib/CodeGen/CGBuiltin.cpp | 33 ++++++++++++++++++++++-
clang/test/CodeGen/math-libcalls-tbaa.cpp | 22 +++++++++++++++
2 files changed, 54 insertions(+), 1 deletion(-)
create mode 100644 clang/test/CodeGen/math-libcalls-tbaa.cpp
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 08a89bd123d03..dc4af109cdbdb 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -707,7 +707,38 @@ static RValue emitLibraryCall(CodeGenFunction &CGF, const FunctionDecl *FD,
const CallExpr *E, llvm::Constant *calleeValue) {
CodeGenFunction::CGFPOptionsRAII FPOptsRAII(CGF, E);
CGCallee callee = CGCallee::forDirect(calleeValue, GlobalDecl(FD));
- return CGF.EmitCall(E->getCallee()->getType(), callee, E, ReturnValueSlot());
+ RValue Call =
+ CGF.EmitCall(E->getCallee()->getType(), callee, E, ReturnValueSlot());
+
+ // Check the supported intrinsic.
+ if (unsigned BuiltinID = FD->getBuiltinID()) {
+ auto IntrinsicID = [&]() -> unsigned {
+ switch (BuiltinID) {
+ case Builtin::BIexpf:
+ case Builtin::BI__builtin_expf:
+ case Builtin::BI__builtin_expf128:
+ return true;
+ }
+ // TODO: support more FP math libcalls
+ return false;
+ }();
+
+ if (IntrinsicID) {
+ llvm::MDBuilder MDHelper(CGF.getLLVMContext());
+ MDNode *RootMD;
+ if (CGF.getLangOpts().CPlusPlus)
+ RootMD = MDHelper.createTBAARoot("Simple C++ TBAA");
+ else
+ RootMD = MDHelper.createTBAARoot("Simple C/C++ TBAA");
+ // Emit "int" TBAA metadata on FP math libcalls.
+ MDNode *AliasType = MDHelper.createTBAANode("int", RootMD);
+ MDNode *MDInt = MDHelper.createTBAAStructTagNode(AliasType, AliasType, 0);
+
+ Value *Val = Call.getScalarVal();
+ cast<llvm::Instruction>(Val)->setMetadata(LLVMContext::MD_tbaa, MDInt);
+ }
+ }
+ return Call;
}
/// Emit a call to llvm.{sadd,uadd,ssub,usub,smul,umul}.with.overflow.*
diff --git a/clang/test/CodeGen/math-libcalls-tbaa.cpp b/clang/test/CodeGen/math-libcalls-tbaa.cpp
new file mode 100644
index 0000000000000..d5b0741a476cb
--- /dev/null
+++ b/clang/test/CodeGen/math-libcalls-tbaa.cpp
@@ -0,0 +1,22 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 2
+// RUN: %clang -S -O3 -emit-llvm -o - -x c++ %s | FileCheck %s -check-prefixes=CHECK
+
+#include <math.h>
+
+
+// Emit int TBAA metadata on FP math libcalls, which is useful for alias analysis
+
+// CHECK-LABEL: define dso_local noundef float @_Z3fooPffi
+// CHECK-SAME: (ptr nocapture noundef readonly [[NUM:%.*]], float noundef [[R2INV:%.*]], i32 noundef [[N:%.*]]) local_unnamed_addr #[[ATTR0:[0-9]+]] {
+// CHECK-NEXT: entry:
+// CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[NUM]], i64 40
+// CHECK-NEXT: [[TMP0:%.*]] = load float, ptr [[ARRAYIDX]], align 4, !tbaa [[TBAA6:![0-9]+]]
+// CHECK-NEXT: [[CALL_I:%.*]] = tail call noundef float @expf(float noundef [[TMP0]]) #[[ATTR2:[0-9]+]], !tbaa [[TBAA10:![0-9]+]]
+// CHECK-NEXT: [[MUL:%.*]] = fmul float [[TMP0]], [[CALL_I]]
+// CHECK-NEXT: ret float [[MUL]]
+//
+float foo (float num[], float r2inv, int n) {
+ const float expm2 = std::exp(num[10]); // Emit TBAA metadata on @expf
+ float tmp = expm2 * num[10];
+ return tmp;
+}
>From 9990877a2b9736c684c8cabeb03c6d98a3d078ce Mon Sep 17 00:00:00 2001
From: zhongyunde 00443407 <zhongyunde at huawei.com>
Date: Thu, 20 Jun 2024 02:29:11 -0400
Subject: [PATCH 2/5] Address comment, reuse CodeGenTBAA::getRoot
---
clang/lib/CodeGen/CGBuiltin.cpp | 6 +-----
clang/lib/CodeGen/CodeGenModule.h | 2 ++
clang/lib/CodeGen/CodeGenTBAA.h | 8 ++++----
clang/test/CodeGen/math-libcalls-tbaa.cpp | 20 +++++++++++++++-----
4 files changed, 22 insertions(+), 14 deletions(-)
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index dc4af109cdbdb..3f448e11bca1a 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -725,11 +725,7 @@ static RValue emitLibraryCall(CodeGenFunction &CGF, const FunctionDecl *FD,
if (IntrinsicID) {
llvm::MDBuilder MDHelper(CGF.getLLVMContext());
- MDNode *RootMD;
- if (CGF.getLangOpts().CPlusPlus)
- RootMD = MDHelper.createTBAARoot("Simple C++ TBAA");
- else
- RootMD = MDHelper.createTBAARoot("Simple C/C++ TBAA");
+ MDNode *RootMD = CGF.CGM.getTBAARoot();
// Emit "int" TBAA metadata on FP math libcalls.
MDNode *AliasType = MDHelper.createTBAANode("int", RootMD);
MDNode *MDInt = MDHelper.createTBAAStructTagNode(AliasType, AliasType, 0);
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index 9b63f47ef42cb..ea77007fdc48d 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -783,6 +783,8 @@ class CodeGenModule : public CodeGenTypeCache {
CtorList &getGlobalCtors() { return GlobalCtors; }
CtorList &getGlobalDtors() { return GlobalDtors; }
+ llvm::MDNode *getTBAARoot() { return TBAA->getRoot(); };
+
/// getTBAATypeInfo - Get metadata used to describe accesses to objects of
/// the given type.
llvm::MDNode *getTBAATypeInfo(QualType QTy);
diff --git a/clang/lib/CodeGen/CodeGenTBAA.h b/clang/lib/CodeGen/CodeGenTBAA.h
index 5d9ecec3ff0fe..2a3a73bd3fd34 100644
--- a/clang/lib/CodeGen/CodeGenTBAA.h
+++ b/clang/lib/CodeGen/CodeGenTBAA.h
@@ -140,10 +140,6 @@ class CodeGenTBAA {
llvm::MDNode *Root;
llvm::MDNode *Char;
- /// getRoot - This is the mdnode for the root of the metadata type graph
- /// for this translation unit.
- llvm::MDNode *getRoot();
-
/// getChar - This is the mdnode for "char", which is special, and any types
/// considered to be equivalent to it.
llvm::MDNode *getChar();
@@ -178,6 +174,10 @@ class CodeGenTBAA {
MangleContext &MContext);
~CodeGenTBAA();
+ /// getRoot - This is the mdnode for the root of the metadata type graph
+ /// for this translation unit.
+ llvm::MDNode *getRoot();
+
/// getTypeInfo - Get metadata used to describe accesses to objects of the
/// given type.
llvm::MDNode *getTypeInfo(QualType QTy);
diff --git a/clang/test/CodeGen/math-libcalls-tbaa.cpp b/clang/test/CodeGen/math-libcalls-tbaa.cpp
index d5b0741a476cb..b0a748b86e423 100644
--- a/clang/test/CodeGen/math-libcalls-tbaa.cpp
+++ b/clang/test/CodeGen/math-libcalls-tbaa.cpp
@@ -1,14 +1,16 @@
-// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 2
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
+// The test may fail as time out on windows
+// REQUIRES: system-linux
+
// RUN: %clang -S -O3 -emit-llvm -o - -x c++ %s | FileCheck %s -check-prefixes=CHECK
#include <math.h>
-
// Emit int TBAA metadata on FP math libcalls, which is useful for alias analysis
-// CHECK-LABEL: define dso_local noundef float @_Z3fooPffi
-// CHECK-SAME: (ptr nocapture noundef readonly [[NUM:%.*]], float noundef [[R2INV:%.*]], i32 noundef [[N:%.*]]) local_unnamed_addr #[[ATTR0:[0-9]+]] {
-// CHECK-NEXT: entry:
+// CHECK-LABEL: define dso_local noundef float @_Z3fooPffi(
+// CHECK-SAME: ptr nocapture noundef readonly [[NUM:%.*]], float noundef [[R2INV:%.*]], i32 noundef [[N:%.*]]) local_unnamed_addr #[[ATTR0:[0-9]+]] {
+// CHECK-NEXT: [[ENTRY:.*:]]
// CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i8, ptr [[NUM]], i64 40
// CHECK-NEXT: [[TMP0:%.*]] = load float, ptr [[ARRAYIDX]], align 4, !tbaa [[TBAA6:![0-9]+]]
// CHECK-NEXT: [[CALL_I:%.*]] = tail call noundef float @expf(float noundef [[TMP0]]) #[[ATTR2:[0-9]+]], !tbaa [[TBAA10:![0-9]+]]
@@ -20,3 +22,11 @@ float foo (float num[], float r2inv, int n) {
float tmp = expm2 * num[10];
return tmp;
}
+//.
+// CHECK: [[TBAA6]] = !{[[META7:![0-9]+]], [[META7]], i64 0}
+// CHECK: [[META7]] = !{!"float", [[META8:![0-9]+]], i64 0}
+// CHECK: [[META8]] = !{!"omnipotent char", [[META9:![0-9]+]], i64 0}
+// CHECK: [[META9]] = !{!"Simple C++ TBAA"}
+// CHECK: [[TBAA10]] = !{[[META11:![0-9]+]], [[META11]], i64 0}
+// CHECK: [[META11]] = !{!"int", [[META9]]}
+//.
>From 3f2c23e24e6329d7279aefd7b0b00baaf6a5b2c9 Mon Sep 17 00:00:00 2001
From: zhongyunde 00443407 <zhongyunde at huawei.com>
Date: Sat, 22 Jun 2024 03:30:03 -0400
Subject: [PATCH 3/5] Restrict to target system and update to
createTBAAScalarTypeNode
---
clang/lib/CodeGen/CGBuiltin.cpp | 6 ++++--
clang/test/CodeGen/math-libcalls-tbaa.cpp | 2 +-
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 3f448e11bca1a..71ba267ee1dd1 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -723,11 +723,13 @@ static RValue emitLibraryCall(CodeGenFunction &CGF, const FunctionDecl *FD,
return false;
}();
- if (IntrinsicID) {
+ const llvm::Triple &T = CGF.getTarget().getTriple();
+ // Restrict to Linux because not all targets set errno, such as MacOS.
+ if (IntrinsicID && T.getOS() == llvm::Triple::Linux) {
llvm::MDBuilder MDHelper(CGF.getLLVMContext());
MDNode *RootMD = CGF.CGM.getTBAARoot();
// Emit "int" TBAA metadata on FP math libcalls.
- MDNode *AliasType = MDHelper.createTBAANode("int", RootMD);
+ MDNode *AliasType = MDHelper.createTBAAScalarTypeNode("int", RootMD);
MDNode *MDInt = MDHelper.createTBAAStructTagNode(AliasType, AliasType, 0);
Value *Val = Call.getScalarVal();
diff --git a/clang/test/CodeGen/math-libcalls-tbaa.cpp b/clang/test/CodeGen/math-libcalls-tbaa.cpp
index b0a748b86e423..ef70fa3518a21 100644
--- a/clang/test/CodeGen/math-libcalls-tbaa.cpp
+++ b/clang/test/CodeGen/math-libcalls-tbaa.cpp
@@ -28,5 +28,5 @@ float foo (float num[], float r2inv, int n) {
// CHECK: [[META8]] = !{!"omnipotent char", [[META9:![0-9]+]], i64 0}
// CHECK: [[META9]] = !{!"Simple C++ TBAA"}
// CHECK: [[TBAA10]] = !{[[META11:![0-9]+]], [[META11]], i64 0}
-// CHECK: [[META11]] = !{!"int", [[META9]]}
+// CHECK: [[META11]] = !{!"int", [[META9]], i64 0}
//.
>From 6be8a2a55c325237c1272f15271ffce6860f14b4 Mon Sep 17 00:00:00 2001
From: zhongyunde 00443407 <zhongyunde at huawei.com>
Date: Tue, 25 Jun 2024 01:06:54 -0400
Subject: [PATCH 4/5] support new-struct-path-tbaa and update with
getTBAATypeInfo
---
clang/lib/CodeGen/CGBuiltin.cpp | 15 ++++++++------
clang/lib/CodeGen/CodeGenModule.h | 2 --
clang/lib/CodeGen/CodeGenTBAA.h | 8 ++++----
clang/test/CodeGen/math-libcalls-tbaa.cpp | 25 ++++++++++++++++-------
4 files changed, 31 insertions(+), 19 deletions(-)
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 71ba267ee1dd1..a7970e5b8d10d 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -723,15 +723,18 @@ static RValue emitLibraryCall(CodeGenFunction &CGF, const FunctionDecl *FD,
return false;
}();
- const llvm::Triple &T = CGF.getTarget().getTriple();
- // Restrict to Linux because not all targets set errno, such as MacOS.
- if (IntrinsicID && T.getOS() == llvm::Triple::Linux) {
+ // Restrict to target with errno, for example, MacOS doesn't set errno.
+ if (IntrinsicID && CGF.CGM.getLangOpts().MathErrno) {
llvm::MDBuilder MDHelper(CGF.getLLVMContext());
- MDNode *RootMD = CGF.CGM.getTBAARoot();
+ ASTContext &Context = CGF.getContext();
// Emit "int" TBAA metadata on FP math libcalls.
- MDNode *AliasType = MDHelper.createTBAAScalarTypeNode("int", RootMD);
+ clang::QualType IntTy = Context.IntTy;
+ MDNode *AliasType = CGF.CGM.getTBAATypeInfo(IntTy);
MDNode *MDInt = MDHelper.createTBAAStructTagNode(AliasType, AliasType, 0);
-
+ if (CGF.CGM.getCodeGenOpts().NewStructPathTBAA) {
+ uint64_t Size = Context.getTypeSizeInChars(IntTy).getQuantity();
+ MDInt = MDHelper.createTBAAAccessTag(AliasType, AliasType, 0, Size);
+ }
Value *Val = Call.getScalarVal();
cast<llvm::Instruction>(Val)->setMetadata(LLVMContext::MD_tbaa, MDInt);
}
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index ea77007fdc48d..9b63f47ef42cb 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -783,8 +783,6 @@ class CodeGenModule : public CodeGenTypeCache {
CtorList &getGlobalCtors() { return GlobalCtors; }
CtorList &getGlobalDtors() { return GlobalDtors; }
- llvm::MDNode *getTBAARoot() { return TBAA->getRoot(); };
-
/// getTBAATypeInfo - Get metadata used to describe accesses to objects of
/// the given type.
llvm::MDNode *getTBAATypeInfo(QualType QTy);
diff --git a/clang/lib/CodeGen/CodeGenTBAA.h b/clang/lib/CodeGen/CodeGenTBAA.h
index 2a3a73bd3fd34..5d9ecec3ff0fe 100644
--- a/clang/lib/CodeGen/CodeGenTBAA.h
+++ b/clang/lib/CodeGen/CodeGenTBAA.h
@@ -140,6 +140,10 @@ class CodeGenTBAA {
llvm::MDNode *Root;
llvm::MDNode *Char;
+ /// getRoot - This is the mdnode for the root of the metadata type graph
+ /// for this translation unit.
+ llvm::MDNode *getRoot();
+
/// getChar - This is the mdnode for "char", which is special, and any types
/// considered to be equivalent to it.
llvm::MDNode *getChar();
@@ -174,10 +178,6 @@ class CodeGenTBAA {
MangleContext &MContext);
~CodeGenTBAA();
- /// getRoot - This is the mdnode for the root of the metadata type graph
- /// for this translation unit.
- llvm::MDNode *getRoot();
-
/// getTypeInfo - Get metadata used to describe accesses to objects of the
/// given type.
llvm::MDNode *getTypeInfo(QualType QTy);
diff --git a/clang/test/CodeGen/math-libcalls-tbaa.cpp b/clang/test/CodeGen/math-libcalls-tbaa.cpp
index ef70fa3518a21..37cf5dae10f40 100644
--- a/clang/test/CodeGen/math-libcalls-tbaa.cpp
+++ b/clang/test/CodeGen/math-libcalls-tbaa.cpp
@@ -2,7 +2,8 @@
// The test may fail as time out on windows
// REQUIRES: system-linux
-// RUN: %clang -S -O3 -emit-llvm -o - -x c++ %s | FileCheck %s -check-prefixes=CHECK
+// RUN: %clang -S -O3 -emit-llvm -o - -x c++ %s | FileCheck %s -check-prefixes=CHECK,NoNewStructPathTBAA
+// RUN: %clang -S -O3 -Xclang -new-struct-path-tbaa -emit-llvm -o - -x c++ %s | FileCheck %s -check-prefixes=CHECK,NewStructPathTBAA
#include <math.h>
@@ -23,10 +24,20 @@ float foo (float num[], float r2inv, int n) {
return tmp;
}
//.
-// CHECK: [[TBAA6]] = !{[[META7:![0-9]+]], [[META7]], i64 0}
-// CHECK: [[META7]] = !{!"float", [[META8:![0-9]+]], i64 0}
-// CHECK: [[META8]] = !{!"omnipotent char", [[META9:![0-9]+]], i64 0}
-// CHECK: [[META9]] = !{!"Simple C++ TBAA"}
-// CHECK: [[TBAA10]] = !{[[META11:![0-9]+]], [[META11]], i64 0}
-// CHECK: [[META11]] = !{!"int", [[META9]], i64 0}
+// NoNewStructPathTBAA: [[TBAA6]] = !{[[META7:![0-9]+]], [[META7]], i64 0}
+// NoNewStructPathTBAA: [[META7]] = !{!"float", [[META8:![0-9]+]], i64 0}
+// NoNewStructPathTBAA: [[META8]] = !{!"omnipotent char", [[META9:![0-9]+]], i64 0}
+// NoNewStructPathTBAA: [[META9]] = !{!"Simple C++ TBAA"}
+// NoNewStructPathTBAA: [[TBAA10]] = !{[[META11:![0-9]+]], [[META11]], i64 0}
+// NoNewStructPathTBAA: [[META11]] = !{!"int", [[META8]], i64 0}
//.
+// NewStructPathTBAA: [[TBAA6]] = !{[[META7:![0-9]+]], [[META7]], i64 0, i64 4}
+// NewStructPathTBAA: [[META7]] = !{[[META8:![0-9]+]], i64 4, !"float"}
+// NewStructPathTBAA: [[META8]] = !{[[META9:![0-9]+]], i64 1, !"omnipotent char"}
+// NewStructPathTBAA: [[META9]] = !{!"Simple C++ TBAA"}
+// NewStructPathTBAA: [[TBAA10]] = !{[[META11:![0-9]+]], [[META11]], i64 0, i64 4}
+// NewStructPathTBAA: [[META11]] = !{[[META8]], i64 4, !"int"}
+//.
+//// NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+// NewStructPathTBAA: {{.*}}
+// NoNewStructPathTBAA: {{.*}}
>From e785613ab86b3d6f2c9c700d7b063075d084d22d Mon Sep 17 00:00:00 2001
From: zhongyunde 00443407 <zhongyunde at huawei.com>
Date: Wed, 26 Jun 2024 01:07:04 -0400
Subject: [PATCH 5/5] Updata with getTBAAAccessTagInfo
---
clang/lib/CodeGen/CGBuiltin.cpp | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index a7970e5b8d10d..634063a226e47 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -729,14 +729,10 @@ static RValue emitLibraryCall(CodeGenFunction &CGF, const FunctionDecl *FD,
ASTContext &Context = CGF.getContext();
// Emit "int" TBAA metadata on FP math libcalls.
clang::QualType IntTy = Context.IntTy;
- MDNode *AliasType = CGF.CGM.getTBAATypeInfo(IntTy);
- MDNode *MDInt = MDHelper.createTBAAStructTagNode(AliasType, AliasType, 0);
- if (CGF.CGM.getCodeGenOpts().NewStructPathTBAA) {
- uint64_t Size = Context.getTypeSizeInChars(IntTy).getQuantity();
- MDInt = MDHelper.createTBAAAccessTag(AliasType, AliasType, 0, Size);
- }
- Value *Val = Call.getScalarVal();
- cast<llvm::Instruction>(Val)->setMetadata(LLVMContext::MD_tbaa, MDInt);
+ TBAAAccessInfo TBAAInfo = CGF.CGM.getTBAAAccessInfo(IntTy);
+ MDNode *Tag = CGF.CGM.getTBAAAccessTagInfo(TBAAInfo);
+ Instruction *Inst = cast<llvm::Instruction>(Call.getScalarVal());
+ Inst->setMetadata(LLVMContext::MD_tbaa, Tag);
}
}
return Call;
More information about the cfe-commits
mailing list