fp-stack-2results.ll   [plain text]

; RUN: llc < %s -march=x86 | grep fldz
; RUN: llc < %s -march=x86-64 | grep fld1

%0 = type { x86_fp80, x86_fp80 }

; This is basically this code on x86-64:
; _Complex long double test() { return 1.0; }
define %0 @test() {
  %A = fpext double 1.0 to x86_fp80
  %B = fpext double 0.0 to x86_fp80
  %mrv = insertvalue %0 undef, x86_fp80 %A, 0
  %mrv1 = insertvalue %0 %mrv, x86_fp80 %B, 1
  ret %0 %mrv1
}


;_test2:
;	fld1
;	fld	%st(0)
;	ret
define %0 @test2() {
  %A = fpext double 1.0 to x86_fp80
  %mrv = insertvalue %0 undef, x86_fp80 %A, 0
  %mrv1 = insertvalue %0 %mrv, x86_fp80 %A, 1
  ret %0 %mrv1
}

; Uses both values.
define void @call1(x86_fp80 *%P1, x86_fp80 *%P2) {
  %a = call %0 @test()
  %b = extractvalue %0 %a, 0
  store x86_fp80 %b, x86_fp80* %P1

  %c = extractvalue %0 %a, 1
  store x86_fp80 %c, x86_fp80* %P2
  ret void 
}

; Uses both values, requires fxch
define void @call2(x86_fp80 *%P1, x86_fp80 *%P2) {
  %a = call %0 @test()
  %b = extractvalue %0 %a, 1
  store x86_fp80 %b, x86_fp80* %P1

  %c = extractvalue %0 %a, 0
  store x86_fp80 %c, x86_fp80* %P2
  ret void
}

; Uses ST(0), ST(1) is dead but must be popped.
define void @call3(x86_fp80 *%P1, x86_fp80 *%P2) {
  %a = call %0 @test()
  %b = extractvalue %0 %a, 0
  store x86_fp80 %b, x86_fp80* %P1
  ret void 
}

; Uses ST(1), ST(0) is dead and must be popped.
define void @call4(x86_fp80 *%P1, x86_fp80 *%P2) {
  %a = call %0 @test()

  %c = extractvalue %0 %a, 1
  store x86_fp80 %c, x86_fp80* %P2
  ret void 
}