[SEH] [ARM64] Retrieve the frame pointer from SEH funclets

The Windows ARM64 runtime passes the establisher frame to funclets as the first
argument.

llvm-svn: 351404

2 files changed, 132 insertions, 0 deletions

diff --git a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
index 621aa8bc783a..5719cf34c954 100644
--- a/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64FrameLowering.cpp
@@ -923,6 +923,17 @@ void AArch64FrameLowering::emitPrologue(MachineFunction &MF,
     if (NeedsWinCFI)
       BuildMI(MBB, MBBI, DL, TII->get(AArch64::SEH_PrologEnd))
           .setMIFlag(MachineInstr::FrameSetup);
+
+    // SEH funclets are passed the frame pointer in X1.  If the parent
+    // function uses the base register, then the base register is used
+    // directly, and is not retrieved from X1.
+    if (F.hasPersonalityFn()) {
+      EHPersonality Per = classifyEHPersonality(F.getPersonalityFn());
+      if (isAsynchronousEHPersonality(Per))
+        BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::COPY), AArch64::FP)
+            .addReg(AArch64::X1).setMIFlag(MachineInstr::FrameSetup);
+    }
+
     return;
   }
 
diff --git a/llvm/test/CodeGen/AArch64/seh_funclet_x1.ll b/llvm/test/CodeGen/AArch64/seh_funclet_x1.ll
new file mode 100644
index 000000000000..b6b84c0e62bd
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/seh_funclet_x1.ll
@@ -0,0 +1,121 @@
+; RUN: llc -o - %s -mtriple=aarch64-windows | FileCheck %s
+
+; Windows runtime passes the establisher frame as the second argument to the
+; termination handler.  Check that we copy it into fp.
+
+; CHECK:      ?dtor$3@?0?main@4HA":
+; CHECK:      .seh_proc "?dtor$3@?0?main@4HA"
+; CHECK:      stp     x29, x30, [sp, #-16]!   ; 16-byte Folded Spill
+; CHECK-NEXT: mov     x29, x1
+
+target datalayout = "e-m:w-p:64:64-i32:32-i64:64-i128:128-n32:64-S128"
+target triple = "aarch64-unknown-windows-msvc19.15.26732"
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @main() #0 personality i8* bitcast (i32 (...)* @__C_specific_handler to i8*) {
+entry:
+  %retval = alloca i32, align 4
+  %Counter = alloca i32, align 4
+  %__exception_code = alloca i32, align 4
+  call void (...) @llvm.localescape(i32* %Counter)
+  store i32 0, i32* %retval, align 4
+  store i32 0, i32* %Counter, align 4
+  %call = invoke i32 bitcast (i32 (...)* @RaiseStatus to i32 (i32)*)(i32 -1073741675) #3
+          to label %invoke.cont unwind label %ehcleanup
+
+invoke.cont:                                      ; preds = %entry
+  %0 = call i8* @llvm.localaddress()
+  invoke void @"?fin$0@0@main@@"(i8 0, i8* %0) #3
+          to label %invoke.cont1 unwind label %catch.dispatch
+
+invoke.cont1:                                     ; preds = %invoke.cont
+  br label %__try.cont
+
+ehcleanup:                                        ; preds = %entry
+  %1 = cleanuppad within none []
+  %2 = call i8* @llvm.localaddress()
+  invoke void @"?fin$0@0@main@@"(i8 1, i8* %2) #3 [ "funclet"(token %1) ]
+          to label %invoke.cont2 unwind label %catch.dispatch
+
+invoke.cont2:                                     ; preds = %ehcleanup
+  cleanupret from %1 unwind label %catch.dispatch
+
+catch.dispatch:                                   ; preds = %invoke.cont2, %ehcleanup, %invoke.cont
+  %3 = catchswitch within none [label %__except] unwind to caller
+
+__except:                                         ; preds = %catch.dispatch
+  %4 = catchpad within %3 [i8* null]
+  catchret from %4 to label %__except3
+
+__except3:                                        ; preds = %__except
+  %5 = call i32 @llvm.eh.exceptioncode(token %4)
+  store i32 %5, i32* %__exception_code, align 4
+  %6 = load i32, i32* %Counter, align 4
+  %add = add nsw i32 %6, 5
+  store i32 %add, i32* %Counter, align 4
+  br label %__try.cont
+
+__try.cont:                                       ; preds = %__except3, %invoke.cont1
+  %7 = load i32, i32* %retval, align 4
+  ret i32 %7
+}
+
+define internal void @"?fin$0@0@main@@"(i8 %abnormal_termination, i8* %frame_pointer) {
+entry:
+  %frame_pointer.addr = alloca i8*, align 8
+  %abnormal_termination.addr = alloca i8, align 1
+  %0 = call i8* @llvm.localrecover(i8* bitcast (i32 ()* @main to i8*), i8* %frame_pointer, i32 0)
+  %Counter = bitcast i8* %0 to i32*
+  store i8* %frame_pointer, i8** %frame_pointer.addr, align 8
+  store i8 %abnormal_termination, i8* %abnormal_termination.addr, align 1
+  store i32 3, i32* %Counter, align 4
+  call void @"?fin$1@0@main@@"(i8 0, i8* %frame_pointer)
+  %1 = load i32, i32* %Counter, align 4
+  %add = add nsw i32 %1, 2
+  store i32 %add, i32* %Counter, align 4
+  %call = call i32 bitcast (i32 (...)* @RaiseStatus to i32 (i32)*)(i32 -1073741675)
+  ret void
+}
+
+; Function Attrs: nounwind readnone
+declare i8* @llvm.localrecover(i8*, i8*, i32) #1
+
+define internal void @"?fin$1@0@main@@"(i8 %abnormal_termination, i8* %frame_pointer) {
+entry:
+  %frame_pointer.addr = alloca i8*, align 8
+  %abnormal_termination.addr = alloca i8, align 1
+  %0 = call i8* @llvm.localrecover(i8* bitcast (i32 ()* @main to i8*), i8* %frame_pointer, i32 0)
+  %Counter = bitcast i8* %0 to i32*
+  store i8* %frame_pointer, i8** %frame_pointer.addr, align 8
+  store i8 %abnormal_termination, i8* %abnormal_termination.addr, align 1
+  %1 = load i32, i32* %Counter, align 4
+  %cmp = icmp eq i32 %1, 3
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  %2 = load i32, i32* %Counter, align 4
+  %add = add nsw i32 %2, 1
+  store i32 %add, i32* %Counter, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %entry
+  ret void
+}
+
+declare dso_local i32 @RaiseStatus(...)
+
+declare dso_local i32 @__C_specific_handler(...)
+
+; Function Attrs: nounwind readnone
+declare i8* @llvm.localaddress() #1
+
+; Function Attrs: nounwind readnone
+declare i32 @llvm.eh.exceptioncode(token) #1
+
+; Function Attrs: nounwind
+declare void @llvm.localescape(...) #2
+
+attributes #0 = { noinline nounwind optnone uwtable }
+attributes #1 = { nounwind readnone }
+attributes #2 = { nounwind }
+attributes #3 = { noinline }