1 files changed, 66 insertions, 32 deletions

diff --git a/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp b/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp
index a6a2c0bf06ae..4209bc333f23 100644
--- a/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp
+++ b/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp
@@ -24,10 +24,11 @@
 #include "WebAssemblyMachineFunctionInfo.h"
 #include "WebAssemblySubtarget.h"
 #include "WebAssemblyTargetMachine.h"
+#include "WebAssemblyUtilities.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
-#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineModuleInfoImpls.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/Support/Debug.h"
 using namespace llvm;
@@ -101,25 +102,35 @@ static void writeSPToMemory(unsigned SrcReg, MachineFunction &MF,
                             MachineBasicBlock::iterator &InsertAddr,
                             MachineBasicBlock::iterator &InsertStore,
                             const DebugLoc &DL) {
-  const char *ES = "__stack_pointer";
-  auto *SPSymbol = MF.createExternalSymbolName(ES);
-  MachineRegisterInfo &MRI = MF.getRegInfo();
-  const TargetRegisterClass *PtrRC =
-      MRI.getTargetRegisterInfo()->getPointerRegClass(MF);
-  unsigned Zero = MRI.createVirtualRegister(PtrRC);
   const auto *TII = MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
 
-  BuildMI(MBB, InsertAddr, DL, TII->get(WebAssembly::CONST_I32), Zero)
-      .addImm(0);
-  MachineMemOperand *MMO = MF.getMachineMemOperand(
-      MachinePointerInfo(MF.getPSVManager().getExternalSymbolCallEntry(ES)),
-      MachineMemOperand::MOStore, 4, 4);
-  BuildMI(MBB, InsertStore, DL, TII->get(WebAssembly::STORE_I32))
-      .addImm(2)  // p2align
-      .addExternalSymbol(SPSymbol)
-      .addReg(Zero)
-      .addReg(SrcReg)
-      .addMemOperand(MMO);
+  if (MF.getSubtarget<WebAssemblySubtarget>()
+        .getTargetTriple().isOSBinFormatELF()) {
+    const char *ES = "__stack_pointer";
+    auto *SPSymbol = MF.createExternalSymbolName(ES);
+    MachineRegisterInfo &MRI = MF.getRegInfo();
+    const TargetRegisterClass *PtrRC =
+        MRI.getTargetRegisterInfo()->getPointerRegClass(MF);
+    unsigned Zero = MRI.createVirtualRegister(PtrRC);
+
+    BuildMI(MBB, InsertAddr, DL, TII->get(WebAssembly::CONST_I32), Zero)
+        .addImm(0);
+    MachineMemOperand *MMO = MF.getMachineMemOperand(
+        MachinePointerInfo(MF.getPSVManager().getExternalSymbolCallEntry(ES)),
+        MachineMemOperand::MOStore, 4, 4);
+    BuildMI(MBB, InsertStore, DL, TII->get(WebAssembly::STORE_I32))
+        .addImm(2)  // p2align
+        .addExternalSymbol(SPSymbol)
+        .addReg(Zero)
+        .addReg(SrcReg)
+        .addMemOperand(MMO);
+  } else {
+    MachineModuleInfoWasm &MMIW =
+        MF.getMMI().getObjFileInfo<MachineModuleInfoWasm>();
+    BuildMI(MBB, InsertStore, DL, TII->get(WebAssembly::SET_GLOBAL_I32))
+        .addImm(MMIW.getStackPointerGlobal())
+        .addReg(SrcReg);
+  }
 }
 
 MachineBasicBlock::iterator
@@ -151,27 +162,50 @@ void WebAssemblyFrameLowering::emitPrologue(MachineFunction &MF,
   auto &MRI = MF.getRegInfo();
 
   auto InsertPt = MBB.begin();
+  while (InsertPt != MBB.end() && WebAssembly::isArgument(*InsertPt))
+    ++InsertPt;
   DebugLoc DL;
 
   const TargetRegisterClass *PtrRC =
       MRI.getTargetRegisterInfo()->getPointerRegClass(MF);
-  unsigned Zero = MRI.createVirtualRegister(PtrRC);
   unsigned SPReg = WebAssembly::SP32;
   if (StackSize)
     SPReg = MRI.createVirtualRegister(PtrRC);
-  const char *ES = "__stack_pointer";
-  auto *SPSymbol = MF.createExternalSymbolName(ES);
-  BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::CONST_I32), Zero)
-      .addImm(0);
-  MachineMemOperand *LoadMMO = MF.getMachineMemOperand(
-      MachinePointerInfo(MF.getPSVManager().getExternalSymbolCallEntry(ES)),
-      MachineMemOperand::MOLoad, 4, 4);
-  // Load the SP value.
-  BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::LOAD_I32), SPReg)
-      .addImm(2)       // p2align
-      .addExternalSymbol(SPSymbol)
-      .addReg(Zero)    // addr
-      .addMemOperand(LoadMMO);
+  if (MF.getSubtarget<WebAssemblySubtarget>()
+        .getTargetTriple().isOSBinFormatELF()) {
+    const char *ES = "__stack_pointer";
+    auto *SPSymbol = MF.createExternalSymbolName(ES);
+    unsigned Zero = MRI.createVirtualRegister(PtrRC);
+
+    BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::CONST_I32), Zero)
+        .addImm(0);
+    MachineMemOperand *LoadMMO = MF.getMachineMemOperand(
+        MachinePointerInfo(MF.getPSVManager().getExternalSymbolCallEntry(ES)),
+        MachineMemOperand::MOLoad, 4, 4);
+    // Load the SP value.
+    BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::LOAD_I32), SPReg)
+        .addImm(2)       // p2align
+        .addExternalSymbol(SPSymbol)
+        .addReg(Zero)    // addr
+        .addMemOperand(LoadMMO);
+  } else {
+    auto &MMIW = MF.getMMI().getObjFileInfo<MachineModuleInfoWasm>();
+    if (!MMIW.hasStackPointerGlobal()) {
+      MMIW.setStackPointerGlobal(MMIW.getGlobals().size());
+
+      // Create the stack-pointer global. For now, just use the
+      // Emscripten/Binaryen ABI names.
+      wasm::Global G;
+      G.Type = wasm::ValType::I32;
+      G.Mutable = true;
+      G.InitialValue = 0;
+      G.InitialModule = "env";
+      G.InitialName = "STACKTOP";
+      MMIW.addGlobal(G);
+    }
+    BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::GET_GLOBAL_I32), SPReg)
+        .addImm(MMIW.getStackPointerGlobal());
+  }
 
   bool HasBP = hasBP(MF);
   if (HasBP) {