[XCOFF][obj2yaml] Support SymbolAlignmentAndType as 2 separate fields in YAML. #76828
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@llvm/pr-subscribers-objectyaml Author: None (stephenpeckham) ChangesXCOFF encodes a symbol type and alignment in a single 8-bit field. It is easier to read and write YAML files if the fields can be specified separately. This PR causes obj2yaml to write the fields separately and allows yaml2obj to read either the single combined field or the separate fields. Full diff: https://github.com/llvm/llvm-project/pull/76828.diff 6 Files Affected:
diff --git a/llvm/include/llvm/ObjectYAML/XCOFFYAML.h b/llvm/include/llvm/ObjectYAML/XCOFFYAML.h
index f1e821fe5fa369..dd359ac8e53dd3 100644
--- a/llvm/include/llvm/ObjectYAML/XCOFFYAML.h
+++ b/llvm/include/llvm/ObjectYAML/XCOFFYAML.h
@@ -121,6 +121,9 @@ struct CsectAuxEnt : AuxSymbolEnt {
// Common fields for both XCOFF32 and XCOFF64.
std::optional<uint32_t> ParameterHashIndex;
std::optional<uint16_t> TypeChkSectNum;
+ std::optional<XCOFF::SymbolType> SymbolType;
+ std::optional<uint8_t> SymbolAlignment;
+ // The two previous values can be encoded as a single value.
std::optional<uint8_t> SymbolAlignmentAndType;
std::optional<XCOFF::StorageMappingClass> StorageMappingClass;
@@ -237,6 +240,10 @@ template <> struct ScalarEnumerationTraits<XCOFF::StorageMappingClass> {
static void enumeration(IO &IO, XCOFF::StorageMappingClass &Value);
};
+template <> struct ScalarEnumerationTraits<XCOFF::SymbolType> {
+ static void enumeration(IO &IO, XCOFF::SymbolType &Value);
+};
+
template <> struct ScalarEnumerationTraits<XCOFF::CFileStringType> {
static void enumeration(IO &IO, XCOFF::CFileStringType &Type);
};
diff --git a/llvm/lib/ObjectYAML/XCOFFEmitter.cpp b/llvm/lib/ObjectYAML/XCOFFEmitter.cpp
index ccf768c06aebfe..327440c6b87103 100644
--- a/llvm/lib/ObjectYAML/XCOFFEmitter.cpp
+++ b/llvm/lib/ObjectYAML/XCOFFEmitter.cpp
@@ -23,6 +23,7 @@
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
+using namespace llvm::object;
namespace {
@@ -525,11 +526,19 @@ bool XCOFFWriter::writeRelocations() {
}
void XCOFFWriter::writeAuxSymbol(const XCOFFYAML::CsectAuxEnt &AuxSym) {
+ uint8_t SymAlignAndType = AuxSym.SymbolAlignmentAndType.value_or(0);
+ if (AuxSym.SymbolType)
+ SymAlignAndType = (SymAlignAndType & ~XCOFFCsectAuxRef::SymbolTypeMask) |
+ *AuxSym.SymbolType;
+ if (AuxSym.SymbolAlignment)
+ SymAlignAndType =
+ (SymAlignAndType & ~XCOFFCsectAuxRef::SymbolAlignmentMask) |
+ (*AuxSym.SymbolAlignment << XCOFFCsectAuxRef::SymbolAlignmentBitOffset);
if (Is64Bit) {
W.write<uint32_t>(AuxSym.SectionOrLengthLo.value_or(0));
W.write<uint32_t>(AuxSym.ParameterHashIndex.value_or(0));
W.write<uint16_t>(AuxSym.TypeChkSectNum.value_or(0));
- W.write<uint8_t>(AuxSym.SymbolAlignmentAndType.value_or(0));
+ W.write<uint8_t>(SymAlignAndType);
W.write<uint8_t>(AuxSym.StorageMappingClass.value_or(XCOFF::XMC_PR));
W.write<uint32_t>(AuxSym.SectionOrLengthHi.value_or(0));
W.write<uint8_t>(0);
@@ -538,7 +547,7 @@ void XCOFFWriter::writeAuxSymbol(const XCOFFYAML::CsectAuxEnt &AuxSym) {
W.write<uint32_t>(AuxSym.SectionOrLength.value_or(0));
W.write<uint32_t>(AuxSym.ParameterHashIndex.value_or(0));
W.write<uint16_t>(AuxSym.TypeChkSectNum.value_or(0));
- W.write<uint8_t>(AuxSym.SymbolAlignmentAndType.value_or(0));
+ W.write<uint8_t>(SymAlignAndType);
W.write<uint8_t>(AuxSym.StorageMappingClass.value_or(XCOFF::XMC_PR));
W.write<uint32_t>(AuxSym.StabInfoIndex.value_or(0));
W.write<uint16_t>(AuxSym.StabSectNum.value_or(0));
diff --git a/llvm/lib/ObjectYAML/XCOFFYAML.cpp b/llvm/lib/ObjectYAML/XCOFFYAML.cpp
index 398b09c72170ba..a1eea621a1056e 100644
--- a/llvm/lib/ObjectYAML/XCOFFYAML.cpp
+++ b/llvm/lib/ObjectYAML/XCOFFYAML.cpp
@@ -127,6 +127,16 @@ void ScalarEnumerationTraits<XCOFF::StorageMappingClass>::enumeration(
#undef ECase
}
+void ScalarEnumerationTraits<XCOFF::SymbolType>::enumeration(
+ IO &IO, XCOFF::SymbolType &Value) {
+#define ECase(X) IO.enumCase(Value, #X, XCOFF::X)
+ ECase(XTY_ER);
+ ECase(XTY_SD);
+ ECase(XTY_LD);
+ ECase(XTY_CM);
+#undef ECase
+}
+
void ScalarEnumerationTraits<XCOFFYAML::AuxSymbolType>::enumeration(
IO &IO, XCOFFYAML::AuxSymbolType &Type) {
#define ECase(X) IO.enumCase(Type, #X, XCOFFYAML::X)
@@ -229,6 +239,8 @@ static void auxSymMapping(IO &IO, XCOFFYAML::CsectAuxEnt &AuxSym, bool Is64) {
IO.mapOptional("ParameterHashIndex", AuxSym.ParameterHashIndex);
IO.mapOptional("TypeChkSectNum", AuxSym.TypeChkSectNum);
IO.mapOptional("SymbolAlignmentAndType", AuxSym.SymbolAlignmentAndType);
+ IO.mapOptional("SymbolType", AuxSym.SymbolType);
+ IO.mapOptional("SymbolAlignment", AuxSym.SymbolAlignment);
IO.mapOptional("StorageMappingClass", AuxSym.StorageMappingClass);
if (Is64) {
IO.mapOptional("SectionOrLengthLo", AuxSym.SectionOrLengthLo);
@@ -350,7 +362,8 @@ void MappingTraits<XCOFFYAML::Symbol>::mapping(IO &IO, XCOFFYAML::Symbol &S) {
IO.mapOptional("AuxEntries", S.AuxEntries);
}
-void MappingTraits<XCOFFYAML::StringTable>::mapping(IO &IO, XCOFFYAML::StringTable &Str) {
+void MappingTraits<XCOFFYAML::StringTable>::mapping(
+ IO &IO, XCOFFYAML::StringTable &Str) {
IO.mapOptional("ContentSize", Str.ContentSize);
IO.mapOptional("Length", Str.Length);
IO.mapOptional("Strings", Str.Strings);
diff --git a/llvm/test/tools/obj2yaml/XCOFF/aix.yaml b/llvm/test/tools/obj2yaml/XCOFF/aix.yaml
index fbd5fa0629d10b..9f2f68b646b6f4 100644
--- a/llvm/test/tools/obj2yaml/XCOFF/aix.yaml
+++ b/llvm/test/tools/obj2yaml/XCOFF/aix.yaml
@@ -56,7 +56,8 @@
# CHECK32-NEXT: - Type: AUX_CSECT
# CHECK32-NEXT: ParameterHashIndex: 0
# CHECK32-NEXT: TypeChkSectNum: 0
-# CHECK32-NEXT: SymbolAlignmentAndType: 0
+# CHECK32-NEXT: SymbolType: XTY_ER
+# CHECK32-NEXT: SymbolAlignment: 0
# CHECK32-NEXT: StorageMappingClass: XMC_PR
# CHECK32-NEXT: SectionOrLength: 0
# CHECK32-NEXT: StabInfoIndex: 0
@@ -71,7 +72,8 @@
# CHECK32-NEXT: - Type: AUX_CSECT
# CHECK32-NEXT: ParameterHashIndex: 0
# CHECK32-NEXT: TypeChkSectNum: 0
-# CHECK32-NEXT: SymbolAlignmentAndType: 0
+# CHECK32-NEXT: SymbolType: XTY_ER
+# CHECK32-NEXT: SymbolAlignment: 0
# CHECK32-NEXT: StorageMappingClass: XMC_PR
# CHECK32-NEXT: SectionOrLength: 0
# CHECK32-NEXT: StabInfoIndex: 0
@@ -128,7 +130,8 @@
# CHECK64-NEXT: - Type: AUX_CSECT
# CHECK64-NEXT: ParameterHashIndex: 0
# CHECK64-NEXT: TypeChkSectNum: 0
-# CHECK64-NEXT: SymbolAlignmentAndType: 0
+# CHECK64-NEXT: SymbolType: XTY_ER
+# CHECK64-NEXT: SymbolAlignment: 0
# CHECK64-NEXT: StorageMappingClass: XMC_PR
# CHECK64-NEXT: SectionOrLengthLo: 0
# CHECK64-NEXT: SectionOrLengthHi: 0
@@ -142,7 +145,8 @@
# CHECK64-NEXT: - Type: AUX_CSECT
# CHECK64-NEXT: ParameterHashIndex: 0
# CHECK64-NEXT: TypeChkSectNum: 0
-# CHECK64-NEXT: SymbolAlignmentAndType: 0
+# CHECK64-NEXT: SymbolType: XTY_ER
+# CHECK64-NEXT: SymbolAlignment: 0
# CHECK64-NEXT: StorageMappingClass: XMC_PR
# CHECK64-NEXT: SectionOrLengthLo: 0
# CHECK64-NEXT: SectionOrLengthHi: 0
diff --git a/llvm/test/tools/obj2yaml/XCOFF/aux-symbols.yaml b/llvm/test/tools/obj2yaml/XCOFF/aux-symbols.yaml
index 7f93b8dae0ca9b..2260bb07749898 100644
--- a/llvm/test/tools/obj2yaml/XCOFF/aux-symbols.yaml
+++ b/llvm/test/tools/obj2yaml/XCOFF/aux-symbols.yaml
@@ -34,7 +34,8 @@
# CHECK32-NEXT: - Type: AUX_CSECT
# CHECK32-NEXT: ParameterHashIndex: 1
# CHECK32-NEXT: TypeChkSectNum: 2
-# CHECK32-NEXT: SymbolAlignmentAndType: 41
+# CHECK32-NEXT: SymbolType: XTY_SD
+# CHECK32-NEXT: SymbolAlignment: 5
# CHECK32-NEXT: StorageMappingClass: XMC_PR
# CHECK32-NEXT: SectionOrLength: 3
# CHECK32-NEXT: StabInfoIndex: 4
@@ -54,7 +55,8 @@
# CHECK32-NEXT: - Type: AUX_CSECT
# CHECK32-NEXT: ParameterHashIndex: 1
# CHECK32-NEXT: TypeChkSectNum: 2
-# CHECK32-NEXT: SymbolAlignmentAndType: 17
+# CHECK32-NEXT: SymbolType: XTY_SD
+# CHECK32-NEXT: SymbolAlignment: 2
# CHECK32-NEXT: StorageMappingClass: XMC_PR
# CHECK32-NEXT: SectionOrLength: 4
# CHECK32-NEXT: StabInfoIndex: 5
@@ -105,7 +107,8 @@ Symbols:
- Type: AUX_CSECT
ParameterHashIndex: 1
TypeChkSectNum: 2
- SymbolAlignmentAndType: 41
+ SymbolAlignment: 5
+ SymbolType: XTY_SD
SectionOrLength: 3
StabInfoIndex: 4
StabSectNum: 5
@@ -174,7 +177,8 @@ Symbols:
# CHECK64-NEXT: - Type: AUX_CSECT
# CHECK64-NEXT: ParameterHashIndex: 1
# CHECK64-NEXT: TypeChkSectNum: 2
-# CHECK64-NEXT: SymbolAlignmentAndType: 41
+# CHECK64-NEXT: SymbolType: XTY_SD
+# CHECK64-NEXT: SymbolAlignment: 5
# CHECK64-NEXT: StorageMappingClass: XMC_PR
# CHECK64-NEXT: SectionOrLengthLo: 3
# CHECK64-NEXT: SectionOrLengthHi: 4
@@ -196,7 +200,8 @@ Symbols:
# CHECK64-NEXT: - Type: AUX_CSECT
# CHECK64-NEXT: ParameterHashIndex: 1
# CHECK64-NEXT: TypeChkSectNum: 2
-# CHECK64-NEXT: SymbolAlignmentAndType: 17
+# CHECK64-NEXT: SymbolType: XTY_SD
+# CHECK64-NEXT: SymbolAlignment: 2
# CHECK64-NEXT: StorageMappingClass: XMC_PR
# CHECK64-NEXT: SectionOrLengthLo: 3
# CHECK64-NEXT: SectionOrLengthHi: 4
diff --git a/llvm/tools/obj2yaml/xcoff2yaml.cpp b/llvm/tools/obj2yaml/xcoff2yaml.cpp
index f7c2bae7479895..e426b645cbeff6 100644
--- a/llvm/tools/obj2yaml/xcoff2yaml.cpp
+++ b/llvm/tools/obj2yaml/xcoff2yaml.cpp
@@ -37,7 +37,7 @@ class XCOFFDumper {
Error dumpAuxSyms(XCOFFYAML::Symbol &Sym, const XCOFFSymbolRef &SymbolEntRef);
void dumpFuncAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress);
void dumpExpAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress);
- void dumpCscetAuxSym(XCOFFYAML::Symbol &Sym,
+ void dumpCsectAuxSym(XCOFFYAML::Symbol &Sym,
const object::XCOFFCsectAuxRef &AuxEntPtr);
public:
@@ -204,12 +204,14 @@ void XCOFFDumper::dumpExpAuxSym(XCOFFYAML::Symbol &Sym,
std::make_unique<XCOFFYAML::ExcpetionAuxEnt>(ExceptAuxSym));
}
-void XCOFFDumper::dumpCscetAuxSym(XCOFFYAML::Symbol &Sym,
+void XCOFFDumper::dumpCsectAuxSym(XCOFFYAML::Symbol &Sym,
const object::XCOFFCsectAuxRef &AuxEntPtr) {
XCOFFYAML::CsectAuxEnt CsectAuxSym;
CsectAuxSym.ParameterHashIndex = AuxEntPtr.getParameterHashIndex();
CsectAuxSym.TypeChkSectNum = AuxEntPtr.getTypeChkSectNum();
- CsectAuxSym.SymbolAlignmentAndType = AuxEntPtr.getSymbolAlignmentAndType();
+ CsectAuxSym.SymbolAlignment = AuxEntPtr.getAlignmentLog2();
+ CsectAuxSym.SymbolType =
+ static_cast<XCOFF::SymbolType>(AuxEntPtr.getSymbolType());
CsectAuxSym.StorageMappingClass = AuxEntPtr.getStorageMappingClass();
if (Obj.is64Bit()) {
@@ -237,7 +239,7 @@ Error XCOFFDumper::dumpAuxSyms(XCOFFYAML::Symbol &Sym,
for (uint8_t I = 1; I <= Sym.NumberOfAuxEntries; ++I) {
if (I == Sym.NumberOfAuxEntries && !Obj.is64Bit()) {
- dumpCscetAuxSym(Sym, CsectAuxRef);
+ dumpCsectAuxSym(Sym, CsectAuxRef);
return Error::success();
}
@@ -247,7 +249,7 @@ Error XCOFFDumper::dumpAuxSyms(XCOFFYAML::Symbol &Sym,
if (Obj.is64Bit()) {
XCOFF::SymbolAuxType Type = *Obj.getSymbolAuxType(AuxAddress);
if (Type == XCOFF::SymbolAuxType::AUX_CSECT)
- dumpCscetAuxSym(Sym, CsectAuxRef);
+ dumpCsectAuxSym(Sym, CsectAuxRef);
else if (Type == XCOFF::SymbolAuxType::AUX_FCN)
dumpFuncAuxSym(Sym, AuxAddress);
else if (Type == XCOFF::SymbolAuxType::AUX_EXCEPT)
|
llvm/tools/obj2yaml/xcoff2yaml.cpp
Outdated
| @@ -37,7 +37,7 @@ class XCOFFDumper { | |||
| Error dumpAuxSyms(XCOFFYAML::Symbol &Sym, const XCOFFSymbolRef &SymbolEntRef); | |||
| void dumpFuncAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress); | |||
| void dumpExpAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress); | |||
| void dumpCscetAuxSym(XCOFFYAML::Symbol &Sym, | |||
| void dumpCsectAuxSym(XCOFFYAML::Symbol &Sym, | |||
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Thanks for correcting typo. :)
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This should be fixed separately. No need for a review though.
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I can use a separate PR. But in general, I think fixing minor typos along with functional changes makes life easier for everyone. And the typo is related to the functional change.
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I couldn't find an exact reference from the community guidelines, but it's strongly related to this part of the "How to submit a patch" section describing what a patch must be:
be an isolated change. Independent changes should be submitted as separate patches as this makes reviewing easier.
The norm is to do the nfc fix immediately before landing the real patch.
llvm/lib/ObjectYAML/XCOFFEmitter.cpp
Outdated
| if (AuxSym.SymbolAlignment) | ||
| SymAlignAndType = | ||
| (SymAlignAndType & ~XCOFFCsectAuxRef::SymbolAlignmentMask) | | ||
| (*AuxSym.SymbolAlignment << XCOFFCsectAuxRef::SymbolAlignmentBitOffset); |
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Please add a test case in yaml stating that SymbolAlignmentAndType will be overridden if SymbolType/SymbolAlignment is defined.
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In similar cases in ELF yaml2obj, it is an error to specify both forms. I think the same should apply here (and be tested of course).
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I think it's harmless to allow both forms.
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if both forms in a YAML file, in the source code "SymbolType/SymbolAlignment" will override SymbolAlignment, but the user may not know the rule, I have same opinion as Jame to emit an error to specify both forms.
We use obj2yaml to generate a yaml file and use the yaml as input for llvm test case usually. we rarely write yaml of XCOFF in llvm test case from scratch. since you only output SymbolType/SymbolAlignment in the obj2yaml . if it is difficult to emit error/warning, I am prefer support "SymbolType/SymbolAlignment" not support SymbolAlignment.
llvm/lib/ObjectYAML/XCOFFEmitter.cpp
Outdated
| if (AuxSym.SymbolAlignment) | ||
| SymAlignAndType = | ||
| (SymAlignAndType & ~XCOFFCsectAuxRef::SymbolAlignmentMask) | | ||
| (*AuxSym.SymbolAlignment << XCOFFCsectAuxRef::SymbolAlignmentBitOffset); |
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In similar cases in ELF yaml2obj, it is an error to specify both forms. I think the same should apply here (and be tested of course).
llvm/tools/obj2yaml/xcoff2yaml.cpp
Outdated
| @@ -37,7 +37,7 @@ class XCOFFDumper { | |||
| Error dumpAuxSyms(XCOFFYAML::Symbol &Sym, const XCOFFSymbolRef &SymbolEntRef); | |||
| void dumpFuncAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress); | |||
| void dumpExpAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress); | |||
| void dumpCscetAuxSym(XCOFFYAML::Symbol &Sym, | |||
| void dumpCsectAuxSym(XCOFFYAML::Symbol &Sym, | |||
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This should be fixed separately. No need for a review though.
|
I forgot to add that your testing needs to show what happens if one or both of the fields are missing. |
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Code was added to validate the alignment field. |
llvm/lib/ObjectYAML/XCOFFEmitter.cpp
Outdated
| if (AuxSym.SymbolAlignment) | ||
| SymAlignAndType = | ||
| (SymAlignAndType & ~XCOFFCsectAuxRef::SymbolAlignmentMask) | | ||
| (*AuxSym.SymbolAlignment << XCOFFCsectAuxRef::SymbolAlignmentBitOffset); |
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if both forms in a YAML file, in the source code "SymbolType/SymbolAlignment" will override SymbolAlignment, but the user may not know the rule, I have same opinion as Jame to emit an error to specify both forms.
We use obj2yaml to generate a yaml file and use the yaml as input for llvm test case usually. we rarely write yaml of XCOFF in llvm test case from scratch. since you only output SymbolType/SymbolAlignment in the obj2yaml . if it is difficult to emit error/warning, I am prefer support "SymbolType/SymbolAlignment" not support SymbolAlignment.
| AuxEntries: | ||
| - Type: AUX_CSECT | ||
| SymbolAlignmentAndType: 17 | ||
| SymbolAlignment: 4 |
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if user have YAML as
SymbolAlignmentAndType: 17
SymbolAlignment: 4
I am prefer to emit error or warning in this test scenario as James's suggestion.
| - Type: AUX_CSECT | ||
| SymbolAlignment: 2 | ||
| SymbolType: XTY_SD | ||
| [[SectionOrLength]]: 4 |
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do we need the [[SectionOrLength]]: 4 in this test case ?
| AuxEntries: | ||
| - Type: AUX_FILE | ||
| FileNameOrString: FileName | ||
| FileStringType: XFT_CD |
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and we do not care about the StorageClass: C_FILE when we test the new functionality of the PR. Can we delete it?
| AuxEntries: | ||
| - Type: AUX_CSECT | ||
| SymbolType: XTY_SD | ||
| [[SectionOrLength]]: 4 |
|
|
||
| ## Ensure that SymbolAlignment is in range. | ||
| # RUN: not yaml2obj %s --docnum=2 -o %t 2>&1 | FileCheck %s --check-prefix=ERROR1 | ||
| # ERROR1: Symbol alignment must be less than 32 |
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I am not sure which one is better 32 or 2^32 ?
| FileHeader: | ||
| MagicNumber: 0x1F7 | ||
| Symbols: | ||
| - StorageClass: C_FILE |
| FileHeader: | ||
| MagicNumber: 0x1DF | ||
| Symbols: | ||
| - StorageClass: C_FILE |
| FileHeader: | ||
| MagicNumber: 0x1DF | ||
| Symbols: | ||
| - StorageClass: C_FILE |
llvm/tools/obj2yaml/xcoff2yaml.cpp
Outdated
| @@ -37,7 +37,7 @@ class XCOFFDumper { | |||
| Error dumpAuxSyms(XCOFFYAML::Symbol &Sym, const XCOFFSymbolRef &SymbolEntRef); | |||
| void dumpFuncAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress); | |||
| void dumpExpAuxSym(XCOFFYAML::Symbol &Sym, const uintptr_t AuxAddress); | |||
| void dumpCscetAuxSym(XCOFFYAML::Symbol &Sym, | |||
| void dumpCsectAuxSym(XCOFFYAML::Symbol &Sym, | |||
There was a problem hiding this comment.
I couldn't find an exact reference from the community guidelines, but it's strongly related to this part of the "How to submit a patch" section describing what a patch must be:
be an isolated change. Independent changes should be submitted as separate patches as this makes reviewing easier.
The norm is to do the nfc fix immediately before landing the real patch.
|
Actually, please could you check the buildkit failures: they look to be tied to this PR, so I'm concerned there might be something you've done wrong? |
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I fixed a problem what showed up in the Linux environment. The Windows build failed immediately. |
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Linux passes. Windows fails, probably because of a buildbot error. |
XCOFF encodes a symbol type and alignment in a single 8-bit field. It is easier to read and write YAML files if the fields can be specified separately. This PR causes obj2yaml to write the fields separately and allows yaml2obj to read either the single combined field or the separate fields.