llvm/test/CodeGen/SystemZ/branch-08.ll
Richard Sandiford e2d6f91d63 [SystemZ] Add unsigned compare-and-branch instructions
For some reason I never got around to adding these at the same time as
the signed versions.  No idea why.

I'm not sure whether this SystemZII::BranchC* stuff is useful, or whether
it should just be replaced with an "is normal" flag.  I'll leave that
for later though.

There are some boundary conditions that can be tweaked, such as preferring
unsigned comparisons for equality with [128, 256), and "<= 255" over "< 256",
but again I'll leave those for a separate patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190930 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-18 09:56:40 +00:00

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944 B
LLVM

; Test SystemZInstrInfo::AnalyzeBranch and SystemZInstrInfo::InsertBranch.
;
; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
declare void @foo() noreturn
; Check a case where a separate branch is needed and where the original
; order should be reversed.
define i32 @f1(i32 %a, i32 *%bptr) {
; CHECK-LABEL: f1:
; CHECK: cl %r2, 0(%r3)
; CHECK: jl .L[[LABEL:.*]]
; CHECK: br %r14
; CHECK: .L[[LABEL]]:
; CHECK: brasl %r14, foo@PLT
entry:
%b = load i32 *%bptr
%cmp = icmp ult i32 %a, %b
br i1 %cmp, label %callit, label %return
callit:
call void @foo()
unreachable
return:
ret i32 1
}
; Same again with a fused compare and branch.
define i32 @f2(i32 %a) {
; CHECK-LABEL: f2:
; CHECK: cije %r2, 0, .L[[LABEL:.*]]
; CHECK: br %r14
; CHECK: .L[[LABEL]]:
; CHECK: brasl %r14, foo@PLT
entry:
%cmp = icmp eq i32 %a, 0
br i1 %cmp, label %callit, label %return
callit:
call void @foo()
unreachable
return:
ret i32 1
}