[clang] [lldb] [lldb] Analyze enum promotion type during parsing (PR #115005)
Ilia Kuklin via cfe-commits
cfe-commits at lists.llvm.org
Tue Nov 5 07:21:36 PST 2024
https://github.com/kuilpd updated https://github.com/llvm/llvm-project/pull/115005
>From 5290832b802d98b9d293b6910c0837911ec490c4 Mon Sep 17 00:00:00 2001
From: Ilia Kuklin <ikuklin at accesssoftek.com>
Date: Mon, 4 Nov 2024 14:33:45 +0500
Subject: [PATCH 1/4] [lldb] Analyze enum promotion type during parsing
---
clang/include/clang/AST/Decl.h | 2 +-
.../SymbolFile/DWARF/DWARFASTParserClang.cpp | 95 ++++++++++++++++++-
.../TypeSystem/Clang/TypeSystemClang.cpp | 29 +-----
3 files changed, 100 insertions(+), 26 deletions(-)
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 8c39ef3d5a9fa6..a78e6c92abb22b 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -3891,6 +3891,7 @@ class EnumDecl : public TagDecl {
void setInstantiationOfMemberEnum(ASTContext &C, EnumDecl *ED,
TemplateSpecializationKind TSK);
+public:
/// Sets the width in bits required to store all the
/// non-negative enumerators of this enum.
void setNumPositiveBits(unsigned Num) {
@@ -3902,7 +3903,6 @@ class EnumDecl : public TagDecl {
/// negative enumerators of this enum. (see getNumNegativeBits)
void setNumNegativeBits(unsigned Num) { EnumDeclBits.NumNegativeBits = Num; }
-public:
/// True if this tag declaration is a scoped enumeration. Only
/// possible in C++11 mode.
void setScoped(bool Scoped = true) { EnumDeclBits.IsScoped = Scoped; }
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
index a30d898a93cc4d..a21607c2020161 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -2248,6 +2248,8 @@ size_t DWARFASTParserClang::ParseChildEnumerators(
return 0;
size_t enumerators_added = 0;
+ unsigned NumNegativeBits = 0;
+ unsigned NumPositiveBits = 0;
for (DWARFDIE die : parent_die.children()) {
const dw_tag_t tag = die.Tag();
@@ -2299,11 +2301,102 @@ size_t DWARFASTParserClang::ParseChildEnumerators(
}
if (name && name[0] && got_value) {
- m_ast.AddEnumerationValueToEnumerationType(
+ auto ECD = m_ast.AddEnumerationValueToEnumerationType(
clang_type, decl, name, enum_value, enumerator_byte_size * 8);
++enumerators_added;
+
+ llvm::APSInt InitVal = ECD->getInitVal();
+ // Keep track of the size of positive and negative values.
+ if (InitVal.isUnsigned() || InitVal.isNonNegative()) {
+ // If the enumerator is zero that should still be counted as a positive
+ // bit since we need a bit to store the value zero.
+ unsigned ActiveBits = InitVal.getActiveBits();
+ NumPositiveBits = std::max({NumPositiveBits, ActiveBits, 1u});
+ } else {
+ NumNegativeBits =
+ std::max(NumNegativeBits, (unsigned)InitVal.getSignificantBits());
+ }
}
}
+
+ /// The following code follows the same logic as in Sema::ActOnEnumBody
+ /// clang/lib/Sema/SemaDecl.cpp
+ // If we have an empty set of enumerators we still need one bit.
+ // From [dcl.enum]p8
+ // If the enumerator-list is empty, the values of the enumeration are as if
+ // the enumeration had a single enumerator with value 0
+ if (!NumPositiveBits && !NumNegativeBits)
+ NumPositiveBits = 1;
+
+ clang::QualType qual_type(ClangUtil::GetQualType(clang_type));
+ clang::EnumDecl *enum_decl = qual_type->getAs<clang::EnumType>()->getDecl();
+ enum_decl->setNumPositiveBits(NumPositiveBits);
+ enum_decl->setNumNegativeBits(NumNegativeBits);
+
+ // C++0x N3000 [conv.prom]p3:
+ // An rvalue of an unscoped enumeration type whose underlying
+ // type is not fixed can be converted to an rvalue of the first
+ // of the following types that can represent all the values of
+ // the enumeration: int, unsigned int, long int, unsigned long
+ // int, long long int, or unsigned long long int.
+ // C99 6.4.4.3p2:
+ // An identifier declared as an enumeration constant has type int.
+ // The C99 rule is modified by C23.
+ clang::QualType BestPromotionType;
+ unsigned BestWidth;
+
+ auto &Context = m_ast.getASTContext();
+ unsigned LongWidth = Context.getTargetInfo().getLongWidth();
+ unsigned IntWidth = Context.getTargetInfo().getIntWidth();
+ unsigned CharWidth = Context.getTargetInfo().getCharWidth();
+ unsigned ShortWidth = Context.getTargetInfo().getShortWidth();
+
+ bool is_cpp = Language::LanguageIsCPlusPlus(
+ SymbolFileDWARF::GetLanguage(*parent_die.GetCU()));
+
+ if (NumNegativeBits) {
+ // If there is a negative value, figure out the smallest integer type (of
+ // int/long/longlong) that fits.
+ if (NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
+ BestWidth = CharWidth;
+ } else if (NumNegativeBits <= ShortWidth && NumPositiveBits < ShortWidth) {
+ BestWidth = ShortWidth;
+ } else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
+ BestWidth = IntWidth;
+ } else if (NumNegativeBits <= LongWidth && NumPositiveBits < LongWidth) {
+ BestWidth = LongWidth;
+ } else {
+ BestWidth = Context.getTargetInfo().getLongLongWidth();
+ }
+ BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : qual_type);
+ } else {
+ // If there is no negative value, figure out the smallest type that fits
+ // all of the enumerator values.
+ if (NumPositiveBits <= CharWidth) {
+ BestPromotionType = Context.IntTy;
+ BestWidth = CharWidth;
+ } else if (NumPositiveBits <= ShortWidth) {
+ BestPromotionType = Context.IntTy;
+ BestWidth = ShortWidth;
+ } else if (NumPositiveBits <= IntWidth) {
+ BestWidth = IntWidth;
+ BestPromotionType = (NumPositiveBits == BestWidth || !is_cpp)
+ ? Context.UnsignedIntTy
+ : Context.IntTy;
+ } else if (NumPositiveBits <= LongWidth) {
+ BestWidth = LongWidth;
+ BestPromotionType = (NumPositiveBits == BestWidth || !is_cpp)
+ ? Context.UnsignedLongTy
+ : Context.LongTy;
+ } else {
+ BestWidth = Context.getTargetInfo().getLongLongWidth();
+ BestPromotionType = (NumPositiveBits == BestWidth || !is_cpp)
+ ? Context.UnsignedLongLongTy
+ : Context.LongLongTy;
+ }
+ }
+ enum_decl->setPromotionType(BestPromotionType);
+
return enumerators_added;
}
diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
index f5063175d6e070..68bc81f51e6a92 100644
--- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
+++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
@@ -2341,7 +2341,6 @@ CompilerType TypeSystemClang::CreateEnumerationType(
if (decl_ctx)
decl_ctx->addDecl(enum_decl);
- // TODO: check if we should be setting the promotion type too?
enum_decl->setIntegerType(ClangUtil::GetQualType(integer_clang_type));
enum_decl->setAccess(AS_public); // TODO respect what's in the debug info
@@ -8461,30 +8460,11 @@ bool TypeSystemClang::CompleteTagDeclarationDefinition(
if (enum_decl->isCompleteDefinition())
return true;
- clang::ASTContext &ast = lldb_ast->getASTContext();
-
- /// TODO This really needs to be fixed.
-
QualType integer_type(enum_decl->getIntegerType());
if (!integer_type.isNull()) {
- unsigned NumPositiveBits = 1;
- unsigned NumNegativeBits = 0;
-
- clang::QualType promotion_qual_type;
- // If the enum integer type is less than an integer in bit width,
- // then we must promote it to an integer size.
- if (ast.getTypeSize(enum_decl->getIntegerType()) <
- ast.getTypeSize(ast.IntTy)) {
- if (enum_decl->getIntegerType()->isSignedIntegerType())
- promotion_qual_type = ast.IntTy;
- else
- promotion_qual_type = ast.UnsignedIntTy;
- } else
- promotion_qual_type = enum_decl->getIntegerType();
-
- enum_decl->completeDefinition(enum_decl->getIntegerType(),
- promotion_qual_type, NumPositiveBits,
- NumNegativeBits);
+ enum_decl->completeDefinition(
+ enum_decl->getIntegerType(), enum_decl->getPromotionType(),
+ enum_decl->getNumPositiveBits(), enum_decl->getNumNegativeBits());
}
return true;
}
@@ -8544,7 +8524,8 @@ clang::EnumConstantDecl *TypeSystemClang::AddEnumerationValueToEnumerationType(
bool is_signed = false;
underlying_type.IsIntegerType(is_signed);
- llvm::APSInt value(enum_value_bit_size, is_signed);
+ // APSInt constructor's sign argument is isUnsigned
+ llvm::APSInt value(enum_value_bit_size, !is_signed);
value = enum_value;
return AddEnumerationValueToEnumerationType(enum_type, decl, name, value);
>From b2f5a17fddd324c3c3814b8ca645868999254de8 Mon Sep 17 00:00:00 2001
From: Ilia Kuklin <ikuklin at accesssoftek.com>
Date: Tue, 5 Nov 2024 19:18:41 +0500
Subject: [PATCH 2/4] Fix enum's underlying type retrieval
---
.../Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
index a21607c2020161..520fd40eda4825 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -2328,8 +2328,8 @@ size_t DWARFASTParserClang::ParseChildEnumerators(
if (!NumPositiveBits && !NumNegativeBits)
NumPositiveBits = 1;
- clang::QualType qual_type(ClangUtil::GetQualType(clang_type));
- clang::EnumDecl *enum_decl = qual_type->getAs<clang::EnumType>()->getDecl();
+ clang::EnumDecl *enum_decl =
+ ClangUtil::GetQualType(clang_type)->getAs<clang::EnumType>()->getDecl();
enum_decl->setNumPositiveBits(NumPositiveBits);
enum_decl->setNumNegativeBits(NumNegativeBits);
@@ -2368,7 +2368,8 @@ size_t DWARFASTParserClang::ParseChildEnumerators(
} else {
BestWidth = Context.getTargetInfo().getLongLongWidth();
}
- BestPromotionType = (BestWidth <= IntWidth ? Context.IntTy : qual_type);
+ BestPromotionType =
+ BestWidth <= IntWidth ? Context.IntTy : enum_decl->getIntegerType();
} else {
// If there is no negative value, figure out the smallest type that fits
// all of the enumerator values.
>From 62c801145a2312d2c9339d30cf116fc2e709d630 Mon Sep 17 00:00:00 2001
From: Ilia Kuklin <ikuklin at accesssoftek.com>
Date: Tue, 5 Nov 2024 19:19:14 +0500
Subject: [PATCH 3/4] Add a test
---
.../test/API/lang/cpp/enum_promotion/Makefile | 3 ++
.../enum_promotion/TestCPPEnumPromotion.py | 37 +++++++++++++++++++
.../test/API/lang/cpp/enum_promotion/main.cpp | 22 +++++++++++
3 files changed, 62 insertions(+)
create mode 100644 lldb/test/API/lang/cpp/enum_promotion/Makefile
create mode 100644 lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py
create mode 100644 lldb/test/API/lang/cpp/enum_promotion/main.cpp
diff --git a/lldb/test/API/lang/cpp/enum_promotion/Makefile b/lldb/test/API/lang/cpp/enum_promotion/Makefile
new file mode 100644
index 00000000000000..99998b20bcb050
--- /dev/null
+++ b/lldb/test/API/lang/cpp/enum_promotion/Makefile
@@ -0,0 +1,3 @@
+CXX_SOURCES := main.cpp
+
+include Makefile.rules
diff --git a/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py b/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py
new file mode 100644
index 00000000000000..a4eed53c8d80f2
--- /dev/null
+++ b/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py
@@ -0,0 +1,37 @@
+"""
+Test LLDB type promotion of unscoped enums.
+"""
+
+import lldb
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+class TestCPPEnumPromotion(TestBase):
+
+ @skipIf(debug_info=no_match(["dwarf", "dwo"]))
+ def test(self):
+ self.build()
+ lldbutil.run_to_source_breakpoint(
+ self, "// break here", lldb.SBFileSpec("main.cpp")
+ )
+ UChar_promoted = self.frame().FindVariable("UChar_promoted")
+ UShort_promoted = self.frame().FindVariable("UShort_promoted")
+ UInt_promoted = self.frame().FindVariable("UInt_promoted")
+ SLong_promoted = self.frame().FindVariable("SLong_promoted")
+ ULong_promoted = self.frame().FindVariable("ULong_promoted")
+ NChar_promoted = self.frame().FindVariable("NChar_promoted")
+ NShort_promoted = self.frame().FindVariable("NShort_promoted")
+ NInt_promoted = self.frame().FindVariable("NInt_promoted")
+ NLong_promoted = self.frame().FindVariable("NLong_promoted")
+
+ # Check that LLDB's promoted type is the same as the compiler's
+ self.expect_expr("+EnumUChar::UChar", result_type=UChar_promoted.type.name)
+ self.expect_expr("+EnumUShort::UShort", result_type=UShort_promoted.type.name)
+ self.expect_expr("+EnumUInt::UInt", result_type=UInt_promoted.type.name)
+ self.expect_expr("+EnumSLong::SLong", result_type=SLong_promoted.type.name)
+ self.expect_expr("+EnumULong::ULong", result_type=ULong_promoted.type.name)
+ self.expect_expr("+EnumNChar::NChar", result_type=NChar_promoted.type.name)
+ self.expect_expr("+EnumNShort::NShort", result_type=NShort_promoted.type.name)
+ self.expect_expr("+EnumNInt::NInt", result_type=NInt_promoted.type.name)
+ self.expect_expr("+EnumNLong::NLong", result_type=NLong_promoted.type.name)
diff --git a/lldb/test/API/lang/cpp/enum_promotion/main.cpp b/lldb/test/API/lang/cpp/enum_promotion/main.cpp
new file mode 100644
index 00000000000000..fafb96f6c7b075
--- /dev/null
+++ b/lldb/test/API/lang/cpp/enum_promotion/main.cpp
@@ -0,0 +1,22 @@
+enum EnumUChar { UChar = 1 };
+enum EnumUShort { UShort = 0x101 };
+enum EnumUInt { UInt = 0x10001 };
+enum EnumSLong { SLong = 0x100000001 };
+enum EnumULong { ULong = 0xFFFFFFFFFFFFFFF0 };
+enum EnumNChar { NChar = -1 };
+enum EnumNShort { NShort= -0x101 };
+enum EnumNInt { NInt = -0x10001 };
+enum EnumNLong { NLong = -0x100000001 };
+
+int main() {
+ auto UChar_promoted = +EnumUChar::UChar;
+ auto UShort_promoted = +EnumUShort::UShort;
+ auto UInt_promoted = +EnumUInt::UInt;
+ auto SLong_promoted = +EnumSLong::SLong;
+ auto ULong_promoted = +EnumULong::ULong;
+ auto NChar_promoted = +EnumNChar::NChar;
+ auto NShort_promoted = +EnumNShort::NShort;
+ auto NInt_promoted = +EnumNInt::NInt;
+ auto NLong_promoted = +EnumNLong::NLong;
+ return 0; // break here
+}
>From 19b98ad94b73adeb59025218397ac1903e25d109 Mon Sep 17 00:00:00 2001
From: Ilia Kuklin <ikuklin at accesssoftek.com>
Date: Tue, 5 Nov 2024 20:10:58 +0500
Subject: [PATCH 4/4] Fix formatting
---
lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py | 2 +-
lldb/test/API/lang/cpp/enum_promotion/main.cpp | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py b/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py
index a4eed53c8d80f2..3cf110441a0ae7 100644
--- a/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py
+++ b/lldb/test/API/lang/cpp/enum_promotion/TestCPPEnumPromotion.py
@@ -7,8 +7,8 @@
from lldbsuite.test.lldbtest import *
from lldbsuite.test import lldbutil
-class TestCPPEnumPromotion(TestBase):
+class TestCPPEnumPromotion(TestBase):
@skipIf(debug_info=no_match(["dwarf", "dwo"]))
def test(self):
self.build()
diff --git a/lldb/test/API/lang/cpp/enum_promotion/main.cpp b/lldb/test/API/lang/cpp/enum_promotion/main.cpp
index fafb96f6c7b075..bcdb0adff5d401 100644
--- a/lldb/test/API/lang/cpp/enum_promotion/main.cpp
+++ b/lldb/test/API/lang/cpp/enum_promotion/main.cpp
@@ -4,7 +4,7 @@ enum EnumUInt { UInt = 0x10001 };
enum EnumSLong { SLong = 0x100000001 };
enum EnumULong { ULong = 0xFFFFFFFFFFFFFFF0 };
enum EnumNChar { NChar = -1 };
-enum EnumNShort { NShort= -0x101 };
+enum EnumNShort { NShort = -0x101 };
enum EnumNInt { NInt = -0x10001 };
enum EnumNLong { NLong = -0x100000001 };
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