Fix PR4485.

Avoid unnecessary duplication of operand 0 of X86::FpSET_ST0_80. This duplication would
cause one register to remain on the stack at the function return.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74534 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/X86/inline-asm-fpstack5.ll b/test/CodeGen/X86/inline-asm-fpstack5.ll
new file mode 100644
index 0000000..64f3788
--- /dev/null
+++ b/test/CodeGen/X86/inline-asm-fpstack5.ll
@@ -0,0 +1,15 @@
+; RUN: llvm-as < %s | llc -march=x86
+; PR4485
+
+define void @test(x86_fp80* %a) {
+entry:
+	%0 = load x86_fp80* %a, align 16
+	%1 = fmul x86_fp80 %0, 0xK4006B400000000000000
+	%2 = fmul x86_fp80 %1, 0xK4012F424000000000000
+	tail call void asm sideeffect "fistpl $0", "{st},~{st}"(x86_fp80 %2)
+	%3 = load x86_fp80* %a, align 16
+	%4 = fmul x86_fp80 %3, 0xK4006B400000000000000
+	%5 = fmul x86_fp80 %4, 0xK4012F424000000000000
+	tail call void asm sideeffect "fistpl $0", "{st},~{st}"(x86_fp80 %5)
+	ret void
+}