llvm-mirror/test/CodeGen/AArch64/machine_cse_impdef_killflags.ll
Matthias Braun 2a033e8287 ScheduleDAGInstrs: Ignore dependencies of constant physregs
There is no need to track dependencies for constant physregs, as they
don't change their value no matter in what order you read/write to them.

Differential Revision: https://reviews.llvm.org/D26221

llvm-svn: 286526
2016-11-10 23:46:44 +00:00

26 lines
955 B
LLVM

; RUN: llc < %s -mtriple=aarch64-apple-ios -fast-isel -verify-machineinstrs | FileCheck %s
; Check that the kill flag is cleared between CSE'd instructions on their
; imp-def'd registers.
; The verifier would complain otherwise.
define i64 @csed-impdef-killflag(i64 %a) {
; CHECK-LABEL: csed-impdef-killflag
; CHECK-DAG: orr [[REG1:w[0-9]+]], wzr, #0x1
; CHECK-DAG: orr [[REG2:x[0-9]+]], xzr, #0x2
; CHECK-DAG: orr [[REG3:x[0-9]+]], xzr, #0x3
; CHECK-DAG: cmp x0, #0
; CHECK: csel w[[SELECT_WREG_1:[0-9]+]], wzr, [[REG1]], ne
; CHECK-DAG: csel [[SELECT_XREG_2:x[0-9]+]], [[REG2]], [[REG3]], ne
; CHECK: ubfx [[SELECT_XREG_1:x[0-9]+]], x[[SELECT_WREG_1]], #0, #32
; CHECK-NEXT: add x0, [[SELECT_XREG_2]], [[SELECT_XREG_1]]
; CHECK-NEXT: ret
%1 = icmp ne i64 %a, 0
%2 = select i1 %1, i32 0, i32 1
%3 = icmp ne i64 %a, 0
%4 = select i1 %3, i64 2, i64 3
%5 = zext i32 %2 to i64
%6 = add i64 %4, %5
ret i64 %6
}