[AIX] use the original name as the input to create the new symbol for TLS symbol.

[Esme]

Summary

Currently, an error was reported when a thread local symbol has an invalid name.
D100956 create a new symbol to prefix the TLS symbol name with a dot. When the symbol name is renamed, the error occurs.
This patch uses the original symbol name (name in the symbol table) as the input for the symbol for TOC entry.

[shchenz]

@@ -2601,19 +2603,27 @@ void PPCAIXAsmPrinter::emitEndOfAsmFile(Module &M) {
       SmallString<128> Name;
       StringRef Prefix = ".";
       Name += Prefix;
-      Name += I.first.first->getName();
+      Name += cast<MCSymbolXCOFF>(I.first.first)->getSymbolTableName();

Will this make more sense? I saw for normal global variables, we will use the original symbol name(name in the symbol table) as the input for the symbol for TOC entry. See function MCSection *TargetLoweringObjectFileXCOFF::getSectionForTOCEntry().

[Esme]

Thanks @shchenz 's comments.

[Esme]

In D132348#3738746, @shchenz wrote:

@@ -2601,19 +2603,27 @@ void PPCAIXAsmPrinter::emitEndOfAsmFile(Module &M) {
       SmallString<128> Name;
       StringRef Prefix = ".";
       Name += Prefix;
-      Name += I.first.first->getName();
+      Name += cast<MCSymbolXCOFF>(I.first.first)->getSymbolTableName();

Will this make more sense? I saw for normal global variables, we will use the original symbol name(name in the symbol table) as the input for the symbol for TOC entry. See function MCSection *TargetLoweringObjectFileXCOFF::getSectionForTOCEntry().

Thanks! @shchenz It's much more reasonable than the previous fix. I did not notice that we can get the original name from the symbol table.

[shchenz]

LGTM

[lkail]

LG

llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp

for (auto &I : TOC) {
     MCSectionXCOFF *TCEntry;
     // Setup the csect for the current TC entry. If the variant kind is
     // VK_PPC_AIX_TLSGDM the entry represents the region handle, we create a
     // new symbol to prefix the name with a dot.
     if (I.first.second == MCSymbolRefExpr::VariantKind::VK_PPC_AIX_TLSGDM) {
       SmallString<128> Name;
       StringRef Prefix = ".";
       Name += Prefix;
-      Name += I.first.first->getName();
+      Name += cast<MCSymbolXCOFF>(I.first.first)->getSymbolTableName();
       MCSymbol *S = OutContext.getOrCreateSymbol(Name);
       TCEntry = cast<MCSectionXCOFF>(
           getObjFileLowering().getSectionForTOCEntry(S, TM));
     } else {
       TCEntry = cast<MCSectionXCOFF>(
           getObjFileLowering().getSectionForTOCEntry(I.first.first, TM));
     }
     OutStreamer->switchSection(TCEntry);

llvm/test/CodeGen/PowerPC/aix-xcoff-tls-rename.ll

+; RUN: llc -verify-machineinstrs -mtriple powerpc64-ibm-aix-xcoff -mcpu=pwr4 \
+; RUN:     -mattr=-altivec -data-sections=false -xcoff-traceback-table=false < %s | FileCheck %s
+
+; CHECK:      .extern .__tls_get_addr[PR]
+; CHECK-NEXT: .csect .tdata[TL],2
+; CHECK-NEXT: .globl  _Renamed..24f_f                 # @"f$f"
+; CHECK-NEXT: .rename _Renamed..24f_f,"f$f"
+
+@"f$f" = thread_local global i32 10, align 4
+
+define void @fun() {
+entry:
+  store i32 1, ptr @"f$f", align 4
+  ret void
+}