arm64-dead-register-def-bug.ll
881 Bytes
; RUN: llc -mtriple="arm64-apple-ios" < %s | FileCheck %s
;
; Check that the dead register definition pass is considering implicit defs.
; When rematerializing through truncates, the coalescer may produce instructions
; with dead defs, but live implicit-defs of subregs:
; E.g. dead %x1 = MOVi64imm 2, implicit-def %w1; %x1:GPR64, %w1:GPR32
; These instructions are live, and their definitions should not be rewritten.
;
; <rdar://problem/16492408>
define void @testcase() {
; CHECK: testcase:
; CHECK-NOT: orr xzr, xzr, #0x2
bb1:
%tmp1 = tail call float @ceilf(float 2.000000e+00)
%tmp2 = fptoui float %tmp1 to i64
br i1 undef, label %bb2, label %bb3
bb2:
tail call void @foo()
br label %bb3
bb3:
%tmp3 = trunc i64 %tmp2 to i32
tail call void @bar(i32 %tmp3)
ret void
}
declare void @foo()
declare void @bar(i32)
declare float @ceilf(float) nounwind readnone