Add `.pushsection', `.popsection', and `.previous' directives to Darwin ASM.
There are situations where inline ASM may want to change the section -- for
instance, to create a variable in the .data section. However, it cannot do this
without (potentially) restoring to the wrong section. E.g.:
asm volatile (".section __DATA, __data\n\t"
".globl _fnord\n\t"
"_fnord: .quad 1f\n\t"
".text\n\t"
"1:" :::);
This may be wrong if this is inlined into a function that has a "section"
attribute. The user should use `.pushsection' and `.popsection' here instead.
The addition of `.previous' is added for completeness.
<rdar://problem/12048387>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161477 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCParser/DarwinAsmParser.cpp b/lib/MC/MCParser/DarwinAsmParser.cpp
index 5662fea..18033d0 100644
--- a/lib/MC/MCParser/DarwinAsmParser.cpp
+++ b/lib/MC/MCParser/DarwinAsmParser.cpp
@@ -50,6 +50,9 @@
AddDirectiveHandler<&DarwinAsmParser::ParseDirectiveDumpOrLoad>(".dump");
AddDirectiveHandler<&DarwinAsmParser::ParseDirectiveDumpOrLoad>(".load");
AddDirectiveHandler<&DarwinAsmParser::ParseDirectiveSection>(".section");
+ AddDirectiveHandler<&DarwinAsmParser::ParseDirectivePushSection>(".pushsection");
+ AddDirectiveHandler<&DarwinAsmParser::ParseDirectivePopSection>(".popsection");
+ AddDirectiveHandler<&DarwinAsmParser::ParseDirectivePrevious>(".previous");
AddDirectiveHandler<&DarwinAsmParser::ParseDirectiveSecureLogUnique>(
".secure_log_unique");
AddDirectiveHandler<&DarwinAsmParser::ParseDirectiveSecureLogReset>(
@@ -112,6 +115,9 @@
bool ParseDirectiveDumpOrLoad(StringRef, SMLoc);
bool ParseDirectiveLsym(StringRef, SMLoc);
bool ParseDirectiveSection(StringRef, SMLoc);
+ bool ParseDirectivePushSection(StringRef, SMLoc);
+ bool ParseDirectivePopSection(StringRef, SMLoc);
+ bool ParseDirectivePrevious(StringRef, SMLoc);
bool ParseDirectiveSecureLogReset(StringRef, SMLoc);
bool ParseDirectiveSecureLogUnique(StringRef, SMLoc);
bool ParseDirectiveSubsectionsViaSymbols(StringRef, SMLoc);
@@ -297,7 +303,7 @@
};
-}
+} // end anonymous namespace
bool DarwinAsmParser::ParseSectionSwitch(const char *Segment,
const char *Section,
@@ -457,6 +463,37 @@
return false;
}
+/// ParseDirectivePushSection:
+/// ::= .pushsection identifier (',' identifier)*
+bool DarwinAsmParser::ParseDirectivePushSection(StringRef S, SMLoc Loc) {
+ getStreamer().PushSection();
+
+ if (ParseDirectiveSection(S, Loc)) {
+ getStreamer().PopSection();
+ return true;
+ }
+
+ return false;
+}
+
+/// ParseDirectivePopSection:
+/// ::= .popsection
+bool DarwinAsmParser::ParseDirectivePopSection(StringRef, SMLoc) {
+ if (!getStreamer().PopSection())
+ return TokError(".popsection without corresponding .pushsection");
+ return false;
+}
+
+/// ParseDirectivePrevious:
+/// ::= .previous
+bool DarwinAsmParser::ParseDirectivePrevious(StringRef DirName, SMLoc) {
+ const MCSection *PreviousSection = getStreamer().getPreviousSection();
+ if (PreviousSection == NULL)
+ return TokError(".previous without corresponding .section");
+ getStreamer().SwitchSection(PreviousSection);
+ return false;
+}
+
/// ParseDirectiveSecureLogUnique
/// ::= .secure_log_unique ... message ...
bool DarwinAsmParser::ParseDirectiveSecureLogUnique(StringRef, SMLoc IDLoc) {
@@ -707,4 +744,4 @@
return new DarwinAsmParser;
}
-}
+} // end llvm namespace