no-fpscr-liveness.ll
1.55 KB
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; RUN: llc -o - %s | FileCheck %s
; Make sure we do not try to compute liveness for FPSCR which in this case
; is read before being written to (this is fine because becase FPSCR is
; reserved).
target triple = "thumbv7s-apple-ios"
%struct.wibble = type { double }
@global = common global i32 0, align 4
@global.1 = common global i32 0, align 4
; CHECK-LABEL: eggs:
; CHECK: sub sp, #8
; VMRS instruction comes before any other instruction writing FPSCR:
; CHECK-NOT: vcmp
; CHECK: vmrs {{r[0-9]}}, fpscr
; CHECK; vcmp
; ...
; CHECK: add sp, #8
; CHECK: bx lr
define i32 @eggs(double* nocapture readnone %arg) {
bb:
%tmp = alloca %struct.wibble, align 4
%tmp1 = bitcast %struct.wibble* %tmp to i8*
%tmp2 = tail call i32 @llvm.flt.rounds()
%tmp3 = ptrtoint %struct.wibble* %tmp to i32
%tmp4 = sitofp i32 %tmp3 to double
%tmp5 = fmul double %tmp4, 0x0123456789ABCDEF
%tmp6 = fptosi double %tmp5 to i32
%tmp7 = fcmp une double %tmp5, 0.000000e+00
%tmp8 = sitofp i32 %tmp6 to double
%tmp9 = fcmp une double %tmp5, %tmp8
%tmp10 = and i1 %tmp7, %tmp9
%tmp11 = sext i1 %tmp10 to i32
%tmp12 = add nsw i32 %tmp11, %tmp6
store i32 %tmp12, i32* @global, align 4
%tmp13 = icmp ne i32 %tmp12, 0
%tmp14 = icmp ne i32 %tmp2, 0
%tmp15 = and i1 %tmp14, %tmp13
br i1 %tmp15, label %bb16, label %bb18
bb16: ; preds = %bb
%tmp17 = load i32, i32* @global.1, align 4
br label %bb18
bb18: ; preds = %bb16, %bb
ret i32 undef
}
declare i32 @llvm.flt.rounds()
declare i32 @zot(...)