llvm/test/CodeGen/Thumb2/thumb2-select_xform.ll
Jakob Stoklund Olesen 098c6a547f Use predication instead of pseudo-opcodes when folding into MOVCC.
Now that it is possible to dynamically tie MachineInstr operands,
predicated instructions are possible in SSA form:

  %vreg3<def> = SUBri %vreg1, -2147483647, pred:14, pred:%noreg, %opt:%noreg
  %vreg4<def,tied1> = MOVCCr %vreg3<tied0>, %vreg1, %pred:12, pred:%CPSR

Becomes a predicated SUBri with a tied imp-use:

  SUBri %vreg1, -2147483647, pred:13, pred:%CPSR, opt:%noreg, %vreg1<imp-use,tied0>

This means that any instruction that is safe to move can be folded into
a MOVCC, and the *CC pseudo-instructions are no longer needed.

The test case changes reflect that Thumb2SizeReduce recognizes the
predicated instructions. It didn't understand the pseudos.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163274 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-05 23:58:02 +00:00

40 lines
980 B
LLVM

; RUN: llc < %s -march=thumb -mattr=+thumb2 | FileCheck %s
define i32 @t1(i32 %a, i32 %b, i32 %c) nounwind {
; CHECK: t1
; CHECK: mvn r0, #-2147483648
; CHECK: cmp r2, #10
; CHECK: it le
; CHECK: addle r1, r0
; CHECK: mov r0, r1
%tmp1 = icmp sgt i32 %c, 10
%tmp2 = select i1 %tmp1, i32 0, i32 2147483647
%tmp3 = add i32 %tmp2, %b
ret i32 %tmp3
}
define i32 @t2(i32 %a, i32 %b, i32 %c) nounwind {
; CHECK: t2
; CHECK: cmp r2, #10
; CHECK: it le
; CHECK: addle.w r1, r1, #-2147483648
; CHECK: mov r0, r1
%tmp1 = icmp sgt i32 %c, 10
%tmp2 = select i1 %tmp1, i32 0, i32 2147483648
%tmp3 = add i32 %tmp2, %b
ret i32 %tmp3
}
define i32 @t3(i32 %a, i32 %b, i32 %c, i32 %d) nounwind {
; CHECK: t3
; CHECK: cmp r2, #10
; CHECK: it le
; CHECK: suble r1, #10
; CHECK: mov r0, r1
%tmp1 = icmp sgt i32 %c, 10
%tmp2 = select i1 %tmp1, i32 0, i32 10
%tmp3 = sub i32 %b, %tmp2
ret i32 %tmp3
}