From 0323d4b169279414862174f38ae04add6b747a60 Mon Sep 17 00:00:00 2001
From: Reed Kotler <rkotler@mips.com>
Date: Tue, 20 Aug 2013 20:53:09 +0000
Subject: [PATCH] Add an option which permits the user to specify using a
 bitmask, that various functions be compiled as mips32, without having to add
 attributes. This is useful in certain situations where you don't want to have
 to edit the function attributes in the source. For now it's only an option
 used for the compiler developers when debugging the mips16 port.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188826 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/Mips/MipsOs16.cpp        | 34 ++++++++++++++++++++++++-----
 test/CodeGen/Mips/fp16instrinsmc.ll | 23 +++++++++++++++++++
 2 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/lib/Target/Mips/MipsOs16.cpp b/lib/Target/Mips/MipsOs16.cpp
index 1919077eeb7..5f9b60c6608 100644
--- a/lib/Target/Mips/MipsOs16.cpp
+++ b/lib/Target/Mips/MipsOs16.cpp
@@ -14,9 +14,17 @@
 #define DEBUG_TYPE "mips-os16"
 #include "MipsOs16.h"
 #include "llvm/IR/Module.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 
+
+static cl::opt<std::string> Mips32FunctionMask(
+  "mips32-function-mask",
+  cl::init(""),
+  cl::desc("Force function to be mips32"),
+  cl::Hidden);
+
 namespace {
 
   // Figure out if we need float point based on the function signature.
@@ -85,18 +93,32 @@ namespace llvm {
 
 
 bool MipsOs16::runOnModule(Module &M) {
-  DEBUG(errs() << "Run on Module MipsOs16\n");
+  bool usingMask = Mips32FunctionMask.length() > 0;
+  DEBUG(dbgs() << "Run on Module MipsOs16 \n" << Mips32FunctionMask << "\n");
+  if (usingMask)
+    DEBUG(dbgs() << "using mask \n" << Mips32FunctionMask << "\n");
+  unsigned int functionIndex = 0;
   bool modified = false;
   for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {
     if (F->isDeclaration()) continue;
     DEBUG(dbgs() << "Working on " << F->getName() << "\n");
-    if (needsFP(*F)) {
-      DEBUG(dbgs() << " need to compile as nomips16 \n");
-      F->addFnAttr("nomips16");
+    if (usingMask) {
+      if ((functionIndex < Mips32FunctionMask.length()) &&
+          (Mips32FunctionMask[functionIndex] == '1')) {
+        DEBUG(dbgs() << "mask forced mips32: " << F->getName() << "\n");
+        F->addFnAttr("nomips16");
+      }
+      functionIndex++;
     }
     else {
-      F->addFnAttr("mips16");
-      DEBUG(dbgs() << " no need to compile as nomips16 \n");
+      if (needsFP(*F)) {
+        DEBUG(dbgs() << "os16 forced mips32: " << F->getName() << "\n");
+        F->addFnAttr("nomips16");
+      }
+      else {
+        DEBUG(dbgs() << "os16 forced mips16: " << F->getName() << "\n");
+        F->addFnAttr("mips16");
+      }
     }
   }
   return modified;
diff --git a/test/CodeGen/Mips/fp16instrinsmc.ll b/test/CodeGen/Mips/fp16instrinsmc.ll
index 3c01d560f7c..ff5927948d0 100644
--- a/test/CodeGen/Mips/fp16instrinsmc.ll
+++ b/test/CodeGen/Mips/fp16instrinsmc.ll
@@ -1,4 +1,5 @@
 ; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -soft-float -mips16-hard-float -relocation-model=pic < %s | FileCheck %s -check-prefix=pic
+; RUN: llc -mtriple=mipsel-linux-gnu -march=mipsel -mcpu=mips16 -soft-float -mips16-hard-float -relocation-model=static -mips32-function-mask=1010111 -mips-os16 < %s | FileCheck %s -check-prefix=fmask 
 
 @x = global float 1.500000e+00, align 4
 @xn = global float -1.900000e+01, align 4
@@ -13,6 +14,14 @@
 
 ; Function Attrs: nounwind
 define void @foo1() #0 {
+; fmask: .ent foo1
+; fmask: .set	noreorder
+; fmask: .set	nomacro
+; fmask: .set	noat
+; fmask: .set	at
+; fmask: .set	macro
+; fmask: .set	reorder
+; fmask: .end	foo1
 entry:
   %0 = load float* @x, align 4
   %1 = load float* @one, align 4
@@ -26,6 +35,9 @@ declare float @copysignf(float, float) #1
 
 ; Function Attrs: nounwind
 define void @foo2() #0 {
+; fmask:	.ent	foo2
+; fmask:	save	{{.*}}
+; fmask:	.end	foo2
 entry:
   %0 = load float* @x, align 4
   %1 = load float* @negone, align 4
@@ -37,6 +49,14 @@ entry:
 ; Function Attrs: nounwind
 define void @foo3() #0 {
 entry:
+; fmask: .ent foo3
+; fmask: .set	noreorder
+; fmask: .set	nomacro
+; fmask: .set	noat
+; fmask: .set	at
+; fmask: .set	macro
+; fmask: .set	reorder
+; fmask: .end	foo3
   %0 = load double* @xd, align 8
   %1 = load float* @oned, align 4
   %conv = fpext float %1 to double
@@ -51,6 +71,9 @@ declare double @copysign(double, double) #1
 ; Function Attrs: nounwind
 define void @foo4() #0 {
 entry:
+; fmask:	.ent	foo4
+; fmask:	save	{{.*}}
+; fmask:	.end	foo4
   %0 = load double* @xd, align 8
   %1 = load double* @negoned, align 8
   %call = call double @copysign(double %0, double %1) #2