[llvm] Emit canonical linkage correct function symbol (llvm#166487)

In the call graph section, we were emitting the temporary label
pointing to the start of the function instead of the canonical linkage
correct function symbol. This patch fixes it and updates the
corresponding tests.

Author: Prabhuk

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -1708,7 +1708,6 @@ void AsmPrinter::emitCallGraphSection(const MachineFunction &MF,
   OutStreamer->pushSection();
   OutStreamer->switchSection(FuncCGSection);
 
-  const MCSymbol *FunctionSymbol = getFunctionBegin();
   const Function &F = MF.getFunction();
   // If this function has external linkage or has its address taken and
   // it is not a callback, then anything could call it.
@@ -1747,7 +1746,7 @@ void AsmPrinter::emitCallGraphSection(const MachineFunction &MF,
   // 8) Each unique indirect target type id.
   OutStreamer->emitInt8(CallGraphSectionFormatVersion::V_0);
   OutStreamer->emitInt8(static_cast<uint8_t>(CGFlags));
-  OutStreamer->emitSymbolValue(FunctionSymbol, TM.getProgramPointerSize());
+  OutStreamer->emitSymbolValue(getSymbol(&F), TM.getProgramPointerSize());
   const auto *TypeId = extractNumericCGTypeId(F);
   if (IsIndirectTarget && TypeId)
     OutStreamer->emitInt64(TypeId->getZExtValue());

llvm/test/CodeGen/ARM/call-graph-section-addrtaken.ll

@@ -14,7 +14,6 @@ entry:
 }
 
 ; CHECK: _ZL10myCallbacki:
-; CHECK-NEXT: [[LABEL_FUNC:\.Lfunc_begin[0-9]+]]:
 define internal void @_ZL10myCallbacki(i32 %value) !type !2 {
 entry:
   %sink = alloca i32, align 4
@@ -33,7 +32,7 @@ entry:
 ;; Flags -- Potential indirect target so LSB is set to 1. Other bits are 0.
 ; CHECK-NEXT: .byte   1
 ;; Function Entry PC
-; CHECK-NEXT: .long   [[LABEL_FUNC]]
+; CHECK-NEXT: .long _ZL10myCallbacki
 ;; Function type ID -5212364466660467813
 ; CHECK-NEXT: .long	1154849691
 ; CHECK-NEXT: .long	3081369122

llvm/test/CodeGen/ARM/call-graph-section-assembly.ll

@@ -11,7 +11,6 @@ declare !type !1 i32 @direct_bar(i8)
 declare !type !2 ptr @direct_baz(ptr)
 
 ; CHECK: ball:
-; CHECK-NEXT: [[LABEL_FUNC:\.Lfunc_begin[0-9]+]]:
 define ptr @ball() {
 entry:
   call void @direct_foo()
@@ -42,7 +41,7 @@ entry:
 ;; Flags
 ; CHECK-NEXT: .byte   7
 ;; Function Entry PC
-; CHECK-NEXT: .long   [[LABEL_FUNC]]
+; CHECK-NEXT: .long ball
 ;; Function type ID -- set to 0 as no type metadata attached to function.
 ; CHECK-NEXT: .long   0
 ; CHECK-NEXT: .long   0

llvm/test/CodeGen/ARM/call-graph-section-tailcall.ll

@@ -29,6 +29,6 @@ declare !type !2 i32 @bar(i8 signext)
 
 ; CHECK:      Hex dump of section '.llvm.callgraph':
 ; CHECK-NEXT: 0x00000000 00050000 00008e19 0b7f3326 e3000154
-; CHECK-NEXT: 0x00000010 86bc5981 4b8e3000 05100000 00a150b8
+; CHECK-NEXT: 0x00000010 86bc5981 4b8e3000 05000000 00a150b8
 ;; Verify that the type id 0x308e4b8159bc8654 is in section.
 ; CHECK-NEXT: 0x00000020 3e0cfe3c b2015486 bc59814b 8e30

llvm/test/CodeGen/X86/call-graph-section-addrtaken.ll

@@ -14,7 +14,6 @@ entry:
 }
 
 ; CHECK: _ZL10myCallbacki:
-; CHECK-NEXT: [[LABEL_FUNC:\.Lfunc_begin[0-9]+]]:
 define internal void @_ZL10myCallbacki(i32 %value) !type !2 {
 entry:
   %sink = alloca i32, align 4
@@ -33,6 +32,6 @@ entry:
 ;; Flags -- Potential indirect target so LSB is set to 1. Other bits are 0.
 ; CHECK-NEXT: .byte   1
 ;; Function Entry PC
-; CHECK-NEXT: .quad   [[LABEL_FUNC]]
+; CHECK-NEXT: .quad   _ZL10myCallbacki
 ;; Function type ID
 ; CHECK-NEXT: .quad   -5212364466660467813

llvm/test/CodeGen/X86/call-graph-section-assembly.ll

@@ -11,7 +11,6 @@ declare !type !1 i32 @direct_bar(i8)
 declare !type !2 ptr @direct_baz(ptr)
 
 ; CHECK: ball:
-; CHECK-NEXT: [[LABEL_FUNC:\.Lfunc_begin[0-9]+]]:
 define ptr @ball() {
 entry:
   call void @direct_foo()
@@ -42,7 +41,7 @@ entry:
 ;; Flags
 ; CHECK-NEXT: .byte   7
 ;; Function Entry PC
-; CHECK-NEXT: .quad   [[LABEL_FUNC]]
+; CHECK-NEXT: .quad ball
 ;; Function type ID -- set to 0 as no type metadata attached to function.
 ; CHECK-NEXT: .quad   0
 ;; Number of unique direct callees.