3 files changed, 17 insertions, 10 deletions
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp
index 5ea532e13c9..32d390de40a 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyFrameLowering.cpp
@@ -160,6 +160,7 @@ void WebAssemblyFrameLowering::emitEpilogue(MachineFunction &MF,
   BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::CONST_I32), OffsetReg)
       .addImm(StackSize);
   auto *SPSymbol = MF.createExternalSymbolName("__stack_pointer");
+  // TODO: Fold this add into the const offset field of the store.
   BuildMI(MBB, InsertPt, DL, TII->get(WebAssembly::ADD_I32), WebAssembly::SP32)
       .addReg(WebAssembly::SP32)
       .addReg(OffsetReg);
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyPeephole.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyPeephole.cpp
index 1a8afee8818..5e879e2e04c 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyPeephole.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyPeephole.cpp
@@ -120,7 +120,10 @@ bool WebAssemblyPeephole::runOnMachineFunction(MachineFunction &MF) {
               MachineOperand &MO = MI.getOperand(0);
               unsigned OldReg = MO.getReg();
               unsigned NewReg = Op2.getReg();
-              if (MRI.getRegClass(NewReg) != MRI.getRegClass(OldReg))
+
+              // TODO: Handle SP/physregs in MaybeRewriteToDiscard
+              if (TargetRegisterInfo::isVirtualRegister(NewReg) &&
+                  (MRI.getRegClass(NewReg) != MRI.getRegClass(OldReg)))
                 report_fatal_error("Peephole: call to builtin function with "
                                    "wrong signature, from/to mismatch");
               Changed |= MaybeRewriteToDiscard(OldReg, NewReg, MO, MFI, MRI);
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp
index 95f7326a7d5..46f271c20af 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyRegisterInfo.cpp
@@ -81,15 +81,18 @@ void WebAssemblyRegisterInfo::eliminateFrameIndex(
     auto &MRI = MF.getRegInfo();
     const auto *TII = MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
 
-    unsigned OffsetReg = MRI.createVirtualRegister(&WebAssembly::I32RegClass);
-    BuildMI(MBB, MI, MI.getDebugLoc(), TII->get(WebAssembly::CONST_I32),
-            OffsetReg)
-        .addImm(FrameOffset);
-    BuildMI(MBB, MI, MI.getDebugLoc(), TII->get(WebAssembly::ADD_I32),
-            OffsetReg)
-        .addReg(WebAssembly::SP32)
-        .addReg(OffsetReg);
-    MI.getOperand(FIOperandNum).ChangeToRegister(OffsetReg, /*IsDef=*/false);
+    unsigned FIRegOperand = WebAssembly::SP32;
+    if (FrameOffset) {
+      FIRegOperand = MRI.createVirtualRegister(&WebAssembly::I32RegClass);
+      BuildMI(MBB, MI, MI.getDebugLoc(), TII->get(WebAssembly::CONST_I32),
+              FIRegOperand)
+          .addImm(FrameOffset);
+      BuildMI(MBB, MI, MI.getDebugLoc(), TII->get(WebAssembly::ADD_I32),
+              FIRegOperand)
+          .addReg(WebAssembly::SP32)
+          .addReg(FIRegOperand);
+    }
+    MI.getOperand(FIOperandNum).ChangeToRegister(FIRegOperand, /*IsDef=*/false);
   }
 }