Fix a problem with fast-isel return values introduced in r134018.

We would put the return value from long double functions in the wrong
register.

This fixes gcc.c-torture/execute/conversion.c

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134205 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGen/X86/fp-stack-O0.ll

@@ -0,0 +1,24 @@
+; RUN: llc < %s -O0 | FileCheck %s
+target triple = "x86_64-apple-macosx"
+
+declare x86_fp80 @x1(i32) nounwind
+declare i32 @x2(x86_fp80, x86_fp80) nounwind
+
+; Keep track of the return value.
+; CHECK: test1
+; CHECK: x1
+; Pass arguments on the stack.
+; CHECK-NEXT: movq %rsp, [[RCX:%r..]]
+; Copy constant-pool value.
+; CHECK-NEXT: fldt LCPI
+; CHECK-NEXT: fstpt 16([[RCX]])
+; Copy x1 return value.
+; CHECK-NEXT: fstpt ([[RCX]])
+; CHECK-NEXT: x2
+define i32 @test1() nounwind uwtable ssp {
+entry:
+  %call = call x86_fp80 (...)* bitcast (x86_fp80 (i32)* @x1 to x86_fp80 (...)*)(i32 -1)
+  %call1 = call i32 @x2(x86_fp80 %call, x86_fp80 0xK401EFFFFFFFF00000000)
+  ret i32 %call1
+}
+