[mips][mips16] Re-work the inline assembly stubs to work with IAS. NFC.

Summary:
Previously, we were inserting an InlineAsm statement for each line of the
inline assembly. This works for GAS but it triggers prologue/epilogue
emission when IAS is in use. This caused:
    .set noreorder
    .cpload $25
to be emitted as:
    .set push
    .set reorder
    .set noreorder
    .set pop
    .set push
    .set reorder
    .cpload $25
    .set pop
which led to assembler errors and caused the test to fail.

The whitespace-after-comma changes included in this patch are necessary to
match the output when IAS is in use.

Reviewers: vkalintiris

Subscribers: rkotler, llvm-commits, dsanders

Differential Revision: http://reviews.llvm.org/D13653

llvm-svn: 250895

1 files changed, 99 insertions, 89 deletions

diff --git a/llvm/lib/Target/Mips/Mips16HardFloat.cpp b/llvm/lib/Target/Mips/Mips16HardFloat.cpp
index 6d34f4a1c5f..b2bc7e74c70 100644
--- a/llvm/lib/Target/Mips/Mips16HardFloat.cpp
+++ b/llvm/lib/Target/Mips/Mips16HardFloat.cpp
@@ -40,26 +40,17 @@ namespace {
     const MipsTargetMachine &TM;
   };
 
-  class InlineAsmHelper {
-    LLVMContext &C;
-    BasicBlock *BB;
-  public:
-    InlineAsmHelper(LLVMContext &C_, BasicBlock *BB_) :
-      C(C_), BB(BB_) {
-      }
-
-    void Out(StringRef AsmString) {
-      std::vector<llvm::Type *> AsmArgTypes;
-      std::vector<llvm::Value*> AsmArgs;
-
-      llvm::FunctionType *AsmFTy = llvm::FunctionType::get(Type::getVoidTy(C),
-                                                           AsmArgTypes, false);
-      llvm::InlineAsm *IA = llvm::InlineAsm::get(AsmFTy, AsmString, "", true,
-                                                 /* IsAlignStack */ false,
-                                                 llvm::InlineAsm::AD_ATT);
-      CallInst::Create(IA, AsmArgs, "", BB);
-    }
-  };
+  static void EmitInlineAsm(LLVMContext &C, BasicBlock *BB, StringRef AsmText) {
+    std::vector<llvm::Type *> AsmArgTypes;
+    std::vector<llvm::Value *> AsmArgs;
+
+    llvm::FunctionType *AsmFTy =
+        llvm::FunctionType::get(Type::getVoidTy(C), AsmArgTypes, false);
+    llvm::InlineAsm *IA =
+        llvm::InlineAsm::get(AsmFTy, AsmText, "", true,
+                             /* IsAlignStack */ false, llvm::InlineAsm::AD_ATT);
+    CallInst::Create(IA, AsmArgs, "", BB);
+  }
 
   char Mips16HardFloat::ID = 0;
 }
@@ -195,63 +186,72 @@ static bool needsFPHelperFromSig(Function &F) {
 // We swap between FP and Integer registers to allow Mips16 and Mips32 to
 // interoperate
 //
-static void swapFPIntParams(FPParamVariant PV, Module *M, InlineAsmHelper &IAH,
-                            bool LE, bool ToFP) {
-  //LLVMContext &Context = M->getContext();
-  std::string MI = ToFP? "mtc1 ": "mfc1 ";
+static std::string swapFPIntParams(FPParamVariant PV, Module *M, bool LE,
+                                   bool ToFP) {
+  std::string MI = ToFP ? "mtc1 ": "mfc1 ";
+  std::string AsmText;
+
   switch (PV) {
   case FSig:
-    IAH.Out(MI + "$$4,$$f12");
+    AsmText += MI + "$$4, $$f12\n";
     break;
+
   case FFSig:
-    IAH.Out(MI +"$$4,$$f12");
-    IAH.Out(MI + "$$5,$$f14");
+    AsmText += MI + "$$4, $$f12\n";
+    AsmText += MI + "$$5, $$f14\n";
     break;
+
   case FDSig:
-    IAH.Out(MI + "$$4,$$f12");
+    AsmText += MI + "$$4, $$f12\n";
     if (LE) {
-      IAH.Out(MI + "$$6,$$f14");
-      IAH.Out(MI + "$$7,$$f15");
+      AsmText += MI + "$$6, $$f14\n";
+      AsmText += MI + "$$7, $$f15\n";
     } else {
-      IAH.Out(MI + "$$7,$$f14");
-      IAH.Out(MI + "$$6,$$f15");
+      AsmText += MI + "$$7, $$f14\n";
+      AsmText += MI + "$$6, $$f15\n";
     }
     break;
+
   case DSig:
     if (LE) {
-      IAH.Out(MI + "$$4,$$f12");
-      IAH.Out(MI + "$$5,$$f13");
+      AsmText += MI + "$$4, $$f12\n";
+      AsmText += MI + "$$5, $$f13\n";
     } else {
-      IAH.Out(MI + "$$5,$$f12");
-      IAH.Out(MI + "$$4,$$f13");
+      AsmText += MI + "$$5, $$f12\n";
+      AsmText += MI + "$$4, $$f13\n";
     }
     break;
+
   case DDSig:
     if (LE) {
-      IAH.Out(MI + "$$4,$$f12");
-      IAH.Out(MI + "$$5,$$f13");
-      IAH.Out(MI + "$$6,$$f14");
-      IAH.Out(MI + "$$7,$$f15");
+      AsmText += MI + "$$4, $$f12\n";
+      AsmText += MI + "$$5, $$f13\n";
+      AsmText += MI + "$$6, $$f14\n";
+      AsmText += MI + "$$7, $$f15\n";
     } else {
-      IAH.Out(MI + "$$5,$$f12");
-      IAH.Out(MI + "$$4,$$f13");
-      IAH.Out(MI + "$$7,$$f14");
-      IAH.Out(MI + "$$6,$$f15");
+      AsmText += MI + "$$5, $$f12\n";
+      AsmText += MI + "$$4, $$f13\n";
+      AsmText += MI + "$$7, $$f14\n";
+      AsmText += MI + "$$6, $$f15\n";
     }
     break;
+
   case DFSig:
     if (LE) {
-      IAH.Out(MI + "$$4,$$f12");
-      IAH.Out(MI + "$$5,$$f13");
+      AsmText += MI + "$$4, $$f12\n";
+      AsmText += MI + "$$5, $$f13\n";
     } else {
-      IAH.Out(MI + "$$5,$$f12");
-      IAH.Out(MI + "$$4,$$f13");
+      AsmText += MI + "$$5, $$f12\n";
+      AsmText += MI + "$$4, $$f13\n";
     }
-    IAH.Out(MI + "$$6,$$f14");
+    AsmText += MI + "$$6, $$f14\n";
     break;
+
   case NoSig:
-    return;
+    break;
   }
+
+  return AsmText;
 }
 
 //
@@ -282,61 +282,70 @@ static void assureFPCallStub(Function &F, Module *M,
   FStub->addFnAttr("nomips16");
   FStub->setSection(SectionName);
   BasicBlock *BB = BasicBlock::Create(Context, "entry", FStub);
-  InlineAsmHelper IAH(Context, BB);
-  IAH.Out(".set reorder");
   FPReturnVariant RV = whichFPReturnVariant(FStub->getReturnType());
   FPParamVariant PV = whichFPParamVariantNeeded(F);
-  swapFPIntParams(PV, M, IAH, LE, true);
+
+  std::string AsmText;
+  AsmText += ".set reorder\n";
+  AsmText += swapFPIntParams(PV, M, LE, true);
   if (RV != NoFPRet) {
-    IAH.Out("move $$18, $$31");
-    IAH.Out("jal " + Name);
+    AsmText += "move $$18, $$31\n";
+    AsmText += "jal " + Name + "\n";
   } else {
-    IAH.Out("lui  $$25,%hi(" + Name + ")");
-    IAH.Out("addiu  $$25,$$25,%lo(" + Name + ")" );
+    AsmText += "lui  $$25, %hi(" + Name + ")\n";
+    AsmText += "addiu  $$25, $$25, %lo(" + Name + ")\n";
   }
+
   switch (RV) {
   case FRet:
-    IAH.Out("mfc1 $$2,$$f0");
+    AsmText += "mfc1 $$2, $$f0\n";
     break;
+
   case DRet:
     if (LE) {
-      IAH.Out("mfc1 $$2,$$f0");
-      IAH.Out("mfc1 $$3,$$f1");
+      AsmText += "mfc1 $$2, $$f0\n";
+      AsmText += "mfc1 $$3, $$f1\n";
     } else {
-      IAH.Out("mfc1 $$3,$$f0");
-      IAH.Out("mfc1 $$2,$$f1");
+      AsmText += "mfc1 $$3, $$f0\n";
+      AsmText += "mfc1 $$2, $$f1\n";
     }
     break;
+
   case CFRet:
     if (LE) {
-      IAH.Out("mfc1 $$2,$$f0");
-      IAH.Out("mfc1 $$3,$$f2");
+      AsmText += "mfc1 $$2, $$f0\n";
+      AsmText += "mfc1 $$3, $$f2\n";
     } else {
-      IAH.Out("mfc1 $$3,$$f0");
-      IAH.Out("mfc1 $$3,$$f2");
+      AsmText += "mfc1 $$3, $$f0\n";
+      AsmText += "mfc1 $$3, $$f2\n";
     }
     break;
+
   case CDRet:
     if (LE) {
-      IAH.Out("mfc1 $$4,$$f2");
-      IAH.Out("mfc1 $$5,$$f3");
-      IAH.Out("mfc1 $$2,$$f0");
-      IAH.Out("mfc1 $$3,$$f1");
+      AsmText += "mfc1 $$4, $$f2\n";
+      AsmText += "mfc1 $$5, $$f3\n";
+      AsmText += "mfc1 $$2, $$f0\n";
+      AsmText += "mfc1 $$3, $$f1\n";
 
     } else {
-      IAH.Out("mfc1 $$5,$$f2");
-      IAH.Out("mfc1 $$4,$$f3");
-      IAH.Out("mfc1 $$3,$$f0");
-      IAH.Out("mfc1 $$2,$$f1");
+      AsmText += "mfc1 $$5, $$f2\n";
+      AsmText += "mfc1 $$4, $$f3\n";
+      AsmText += "mfc1 $$3, $$f0\n";
+      AsmText += "mfc1 $$2, $$f1\n";
     }
     break;
+
   case NoFPRet:
     break;
   }
+
   if (RV != NoFPRet)
-    IAH.Out("jr $$18");
+    AsmText += "jr $$18\n";
   else
-    IAH.Out("jr $$25");
+    AsmText += "jr $$25\n";
+  EmitInlineAsm(Context, BB, AsmText);
+
   new UnreachableInst(Context, BB);
 }
 
@@ -469,20 +478,21 @@ static void createFPFnStub(Function *F, Module *M, FPParamVariant PV,
   FStub->addFnAttr("nomips16");
   FStub->setSection(SectionName);
   BasicBlock *BB = BasicBlock::Create(Context, "entry", FStub);
-  InlineAsmHelper IAH(Context, BB);
+
+  std::string AsmText;
   if (PicMode) {
-    IAH.Out(".set noreorder");
-    IAH.Out(".cpload  $$25");
-    IAH.Out(".set reorder");
-    IAH.Out(".reloc 0,R_MIPS_NONE," + Name);
-    IAH.Out("la $$25," + LocalName);
-  }
-  else {
-    IAH.Out("la $$25," + Name);
-  }
-  swapFPIntParams(PV, M, IAH, LE, false);
-  IAH.Out("jr $$25");
-  IAH.Out(LocalName + " = " + Name);
+    AsmText += ".set noreorder\n";
+    AsmText += ".cpload $$25\n";
+    AsmText += ".set reorder\n";
+    AsmText += ".reloc 0, R_MIPS_NONE, " + Name + "\n";
+    AsmText += "la $$25, " + LocalName + "\n";
+  } else
+    AsmText += "la $$25, " + Name + "\n";
+  AsmText += swapFPIntParams(PV, M, LE, false);
+  AsmText += "jr $$25\n";
+  AsmText += LocalName + " = " + Name + "\n";
+  EmitInlineAsm(Context, BB, AsmText);
+
   new UnreachableInst(FStub->getContext(), BB);
 }