[llvm] 3e139be - [SystemZ][z/OS] Add support for function name field of PPA1

[Neumann Hon via llvm-commits]

Author: Neumann Hon
Date: 2023-08-10T04:40:19-04:00
New Revision: 3e139be29f8cd30f5ffab5ddf22dd4c8527cd541

URL: https://github.com/llvm/llvm-project/commit/3e139be29f8cd30f5ffab5ddf22dd4c8527cd541
DIFF: https://github.com/llvm/llvm-project/commit/3e139be29f8cd30f5ffab5ddf22dd4c8527cd541.diff

LOG: [SystemZ][z/OS] Add support for function name field of PPA1

This PR causes the PPA1 to emit the function's name if it exists. This field is not emitted for unnamed functions.

Reviewed By: uweigand

Differential Revision: https://reviews.llvm.org/D157494

Added: 
    

Modified: 
    llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
    llvm/test/CodeGen/SystemZ/zos-prologue-epilog.ll

Removed: 
    


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diff  --git a/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp b/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
index afebdd3f61490c..b89d80453280ca 100644
--- a/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
@@ -27,6 +27,7 @@
 #include "llvm/MC/MCSectionELF.h"
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/TargetRegistry.h"
+#include "llvm/Support/ConvertEBCDIC.h"
 
 using namespace llvm;
 
@@ -1043,7 +1044,8 @@ void SystemZAsmPrinter::emitFunctionBodyEnd() {
 }
 
 static void emitPPA1Flags(std::unique_ptr<MCStreamer> &OutStreamer, bool VarArg,
-                          bool StackProtector, bool FPRMask, bool VRMask) {
+                          bool StackProtector, bool FPRMask, bool VRMask,
+                          bool HasName) {
   enum class PPA1Flag1 : uint8_t {
     DSA64Bit = (0x80 >> 0),
     VarArg = (0x80 >> 7),
@@ -1069,7 +1071,7 @@ static void emitPPA1Flags(std::unique_ptr<MCStreamer> &OutStreamer, bool VarArg,
   auto Flags1 = PPA1Flag1(0);
   auto Flags2 = PPA1Flag2::ExternalProcedure;
   auto Flags3 = PPA1Flag3(0);
-  auto Flags4 = PPA1Flag4::EPMOffsetPresent | PPA1Flag4::ProcedureNamePresent;
+  auto Flags4 = PPA1Flag4::EPMOffsetPresent;
 
   Flags1 |= PPA1Flag1::DSA64Bit;
 
@@ -1086,6 +1088,9 @@ static void emitPPA1Flags(std::unique_ptr<MCStreamer> &OutStreamer, bool VarArg,
   if (VRMask)
     Flags4 |= PPA1Flag4::VRMask; // Add emit VR mask flag.
 
+  if (HasName)
+    Flags4 |= PPA1Flag4::ProcedureNamePresent; // Add optional name block.
+
   OutStreamer->AddComment("PPA1 Flags 1");
   if ((Flags1 & PPA1Flag1::DSA64Bit) == PPA1Flag1::DSA64Bit)
     OutStreamer->AddComment("  Bit 0: 1 = 64-bit DSA");
@@ -1113,10 +1118,37 @@ static void emitPPA1Flags(std::unique_ptr<MCStreamer> &OutStreamer, bool VarArg,
   OutStreamer->AddComment("PPA1 Flags 4");
   if ((Flags4 & PPA1Flag4::VRMask) == PPA1Flag4::VRMask)
     OutStreamer->AddComment("  Bit 2: 1 = Vector Reg Mask is in optional area");
+  if ((Flags4 & PPA1Flag4::ProcedureNamePresent) ==
+      PPA1Flag4::ProcedureNamePresent)
+    OutStreamer->AddComment("  Bit 7: 1 = Name Length and Name");
   OutStreamer->emitInt8(static_cast<uint8_t>(
       Flags4)); // Flags 4 (optional sections, always emit these).
 }
 
+static void emitPPA1Name(std::unique_ptr<MCStreamer> &OutStreamer,
+                         StringRef OutName) {
+  size_t NameSize = OutName.size();
+  uint16_t OutSize;
+  if (NameSize < UINT16_MAX) {
+    OutSize = static_cast<uint16_t>(NameSize);
+  } else {
+    OutName = OutName.substr(0, UINT16_MAX);
+    OutSize = UINT16_MAX;
+  }
+  // Emit padding to ensure that the next optional field word-aligned.
+  uint8_t ExtraZeros = 4 - ((2 + OutSize) % 4);
+
+  SmallString<512> OutnameConv;
+  ConverterEBCDIC::convertToEBCDIC(OutName, OutnameConv);
+  OutName = OutnameConv.str();
+
+  OutStreamer->AddComment("Length of Name");
+  OutStreamer->emitInt16(OutSize);
+  OutStreamer->AddComment("Name of Function");
+  OutStreamer->emitBytes(OutName);
+  OutStreamer->emitZeros(ExtraZeros);
+}
+
 void SystemZAsmPrinter::emitPPA1(MCSymbol *FnEndSym) {
   const TargetRegisterInfo *TRI = MF->getRegInfo().getTargetRegisterInfo();
   const SystemZSubtarget &Subtarget = MF->getSubtarget<SystemZSubtarget>();
@@ -1208,9 +1240,12 @@ void SystemZAsmPrinter::emitPPA1(MCSymbol *FnEndSym) {
   OutStreamer->AddComment("Saved GPR Mask");
   OutStreamer->emitInt16(SavedGPRMask);
 
+  bool HasName =
+      MF->getFunction().hasName() && MF->getFunction().getName().size() > 0;
+
   emitPPA1Flags(OutStreamer, MF->getFunction().isVarArg(),
                 MFFrame.hasStackProtectorIndex(), SavedFPRMask != 0,
-                TargetHasVector && SavedVRMask != 0);
+                TargetHasVector && SavedVRMask != 0, HasName);
 
   OutStreamer->AddComment("Length/4 of Parms");
   OutStreamer->emitInt16(
@@ -1252,6 +1287,10 @@ void SystemZAsmPrinter::emitPPA1(MCSymbol *FnEndSym) {
     OutStreamer->emitInt32(FrameAndVROffset);
   }
 
+  // Emit name length and name optional section (0x01 of flags 4)
+  if (HasName)
+    emitPPA1Name(OutStreamer, MF->getFunction().getName());
+
   // Emit offset to entry point optional section (0x80 of flags 4).
   OutStreamer->emitAbsoluteSymbolDiff(CurrentFnEPMarkerSym, CurrentFnPPA1Sym,
                                       4);

diff  --git a/llvm/test/CodeGen/SystemZ/zos-prologue-epilog.ll b/llvm/test/CodeGen/SystemZ/zos-prologue-epilog.ll
index 510b6188270ab8..202162ed4dd8c8 100644
--- a/llvm/test/CodeGen/SystemZ/zos-prologue-epilog.ll
+++ b/llvm/test/CodeGen/SystemZ/zos-prologue-epilog.ll
@@ -394,6 +394,27 @@ define i64 @leaf_func0(i64 %a, i64 %b, i64 %c) {
   ret i64 %o
 }
 
+
+; =============================
+;     Tests for PPA1 Fields
+; =============================
+; CHECK-LABEL: named_func
+; CHECK: .byte	129  * PPA1 Flags 4
+; CHECK-NEXT: *   Bit 7: 1 = Name Length and Name
+define i64 @named_func(i64 %arg) {
+  %sum = add i64 1, %arg
+  ret i64 %sum
+}
+
+; CHECK-LABEL: __unnamed_1
+; CHECK: .byte	128  * PPA1 Flags 4
+; CHECK-NOT: *   Bit 7: 1 = Name Length and Name
+define void @""(ptr %p) {
+  call i64 (ptr) @fun1(ptr %p)
+  ret void
+}
+
+
 declare i64 @fun(i64 %arg0)
 declare i64 @fun1(ptr %ptr)
 declare i64 @fun2(i64 %n, ptr %arr0, ptr %arr1)