Fix a problem with dual mips16/mips32 mode. When the underlying processor
has hard float, when you compile the mips32 code you have to make sure
that it knows to compile any mips32 routines as hard float. I need to clean
up the way mips16 hard float is specified but I need to first think through
all the details. Mips16 always has a form of soft float, the difference being
whether the underlying hardware has floating point. So it's not really
necessary to pass the -soft-float to llvm since soft-float is always true
for mips16 by virtue of the fact that it will not register floating point
registers. By using this fact, I can simplify the way this is all handled.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189690 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/Mips16HardFloat.cpp b/lib/Target/Mips/Mips16HardFloat.cpp
index 617c178..a66abb2 100644
--- a/lib/Target/Mips/Mips16HardFloat.cpp
+++ b/lib/Target/Mips/Mips16HardFloat.cpp
@@ -430,6 +430,21 @@
   new UnreachableInst(FStub->getContext(), BB);
 }
 
+//
+// remove the use-soft-float attribute
+//
+static void removeUseSoftFloat(Function &F) {
+  AttributeSet A;
+  DEBUG(errs() << "removing -use-soft-float\n");
+  A = A.addAttribute(F.getContext(), AttributeSet::FunctionIndex,
+                     "use-soft-float", "false");
+  F.removeAttributes(AttributeSet::FunctionIndex, A);
+  if (F.hasFnAttribute("use-soft-float")) {
+    DEBUG(errs() << "still has -use-soft-float\n");
+  }
+  F.addAttributes(AttributeSet::FunctionIndex, A);
+}
+
 namespace llvm {
 
 //
@@ -453,6 +468,11 @@
   DEBUG(errs() << "Run on Module Mips16HardFloat\n");
   bool Modified = false;
   for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
+    if (F->hasFnAttribute("nomips16") &&
+        F->hasFnAttribute("use-soft-float")) {
+      removeUseSoftFloat(*F);
+      continue;
+    }
     if (F->isDeclaration() || F->hasFnAttribute("mips16_fp_stub") ||
         F->hasFnAttribute("nomips16")) continue;
     Modified |= fixupFPReturnAndCall(*F, &M, Subtarget);
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index 4d1f329..a1706ab 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -2334,7 +2334,7 @@
                     SpecialCallingConv);
 
   MipsCCInfo.analyzeCallOperands(Outs, IsVarArg,
-                                 getTargetMachine().Options.UseSoftFloat,
+                                 Subtarget->mipsSEUsesSoftFloat(),
                                  Callee.getNode(), CLI.Args);
 
   // Get a count of how many bytes are to be pushed on the stack.
@@ -2520,7 +2520,7 @@
                  getTargetMachine(), RVLocs, *DAG.getContext());
   MipsCC MipsCCInfo(CallConv, IsO32, Subtarget->isFP64bit(), CCInfo);
 
-  MipsCCInfo.analyzeCallResult(Ins, getTargetMachine().Options.UseSoftFloat,
+  MipsCCInfo.analyzeCallResult(Ins, Subtarget->mipsSEUsesSoftFloat(),
                                CallNode, RetTy);
 
   // Copy all of the result registers out of their specified physreg.
@@ -2568,7 +2568,7 @@
   MipsCC MipsCCInfo(CallConv, IsO32, Subtarget->isFP64bit(), CCInfo);
   Function::const_arg_iterator FuncArg =
     DAG.getMachineFunction().getFunction()->arg_begin();
-  bool UseSoftFloat = getTargetMachine().Options.UseSoftFloat;
+  bool UseSoftFloat = Subtarget->mipsSEUsesSoftFloat();
 
   MipsCCInfo.analyzeFormalArguments(Ins, UseSoftFloat, FuncArg);
   MipsFI->setFormalArgInfo(CCInfo.getNextStackOffset(),
@@ -2728,7 +2728,7 @@
   MipsCC MipsCCInfo(CallConv, IsO32, Subtarget->isFP64bit(), CCInfo);
 
   // Analyze return values.
-  MipsCCInfo.analyzeReturn(Outs, getTargetMachine().Options.UseSoftFloat,
+  MipsCCInfo.analyzeReturn(Outs, Subtarget->mipsSEUsesSoftFloat(),
                            MF.getFunction()->getReturnType());
 
   SDValue Flag;
diff --git a/lib/Target/Mips/MipsSEISelLowering.cpp b/lib/Target/Mips/MipsSEISelLowering.cpp
index 9108211..fae294c 100644
--- a/lib/Target/Mips/MipsSEISelLowering.cpp
+++ b/lib/Target/Mips/MipsSEISelLowering.cpp
@@ -87,7 +87,7 @@
     addMSAType(MVT::v2f64, &Mips::MSA128DRegClass);
   }
 
-  if (!TM.Options.UseSoftFloat) {
+  if (!Subtarget->mipsSEUsesSoftFloat()) {
     addRegisterClass(MVT::f32, &Mips::FGR32RegClass);
 
     // When dealing with single precision only, use libcalls
diff --git a/lib/Target/Mips/MipsSubtarget.cpp b/lib/Target/Mips/MipsSubtarget.cpp
index 8383904..91e2535 100644
--- a/lib/Target/Mips/MipsSubtarget.cpp
+++ b/lib/Target/Mips/MipsSubtarget.cpp
@@ -155,3 +155,6 @@
   }
 }
 
+bool MipsSubtarget::mipsSEUsesSoftFloat() const {
+  return TM->Options.UseSoftFloat && !InMips16HardFloat;
+}
diff --git a/lib/Target/Mips/MipsSubtarget.h b/lib/Target/Mips/MipsSubtarget.h
index 03bef69..140ddde 100644
--- a/lib/Target/Mips/MipsSubtarget.h
+++ b/lib/Target/Mips/MipsSubtarget.h
@@ -192,6 +192,8 @@
 
   bool hasStandardEncoding() const { return !inMips16Mode(); }
 
+  bool mipsSEUsesSoftFloat() const;
+
   /// Features related to the presence of specific instructions.
   bool hasSEInReg()   const { return HasSEInReg; }
   bool hasCondMov()   const { return HasCondMov; }
diff --git a/test/CodeGen/Mips/nomips16.ll b/test/CodeGen/Mips/nomips16.ll
new file mode 100644
index 0000000..bf7c667
--- /dev/null
+++ b/test/CodeGen/Mips/nomips16.ll
@@ -0,0 +1,38 @@
+; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -mips16-hard-float -soft-float -relocation-model=static < %s | FileCheck %s 
+
+@x = global float 0.000000e+00, align 4
+@.str = private unnamed_addr constant [20 x i8] c"in main: mips16 %f\0A\00", align 1
+
+; Function Attrs: nounwind
+define void @foo() #0 {
+entry:
+  %0 = load float* @x, align 4
+  %conv = fpext float %0 to double
+  %add = fadd double %conv, 1.500000e+00
+  %conv1 = fptrunc double %add to float
+  store float %conv1, float* @x, align 4
+  ret void
+}
+; CHECK: 	.ent	foo
+; CHECK: 	jal	__mips16_extendsfdf2
+; CHECK:   	.end	foo
+
+; Function Attrs: nounwind
+define void @nofoo() #1 {
+entry:
+  %0 = load float* @x, align 4
+  %conv = fpext float %0 to double
+  %add = fadd double %conv, 3.900000e+00
+  %conv1 = fptrunc double %add to float
+  store float %conv1, float* @x, align 4
+  ret void
+}
+
+; CHECK: 	.ent	nofoo
+; CHECK: 	cvt.d.s	$f{{.+}}, $f{{.+}}
+; CHECK: 	.end	nofoo
+
+
+attributes #0 = { nounwind "less-precise-fpmad"="false" "mips16" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="true" }
+attributes #1 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "nomips16" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="true" }
+