ef160de3e5
Summary: Uniform loops where the branch leaving the loop is predicated on VCCNZ must be skipped if EXEC = 0, otherwise they will be infinite. Reviewers: tstellarAMD, arsenm Subscribers: arsenm, llvm-commits Differential Revision: http://reviews.llvm.org/D18137 llvm-svn: 263658
29 lines
744 B
LLVM
29 lines
744 B
LLVM
;RUN: llc -march=amdgcn -mcpu=verde < %s | FileCheck %s --check-prefix=CHECK
|
|
|
|
; Test a simple uniform loop that lives inside non-uniform control flow.
|
|
|
|
;CHECK-LABEL: {{^}}test1:
|
|
;CHECK: s_cbranch_execz
|
|
;CHECK: %loop_body
|
|
define void @test1(<8 x i32> inreg %rsrc, <2 x i32> %addr.base, i32 %y, i32 %p) #0 {
|
|
main_body:
|
|
%cc = icmp eq i32 %p, 0
|
|
br i1 %cc, label %out, label %loop_body
|
|
|
|
loop_body:
|
|
%counter = phi i32 [ 0, %main_body ], [ %incr, %loop_body ]
|
|
|
|
; Prevent the loop from being optimized out
|
|
call void asm sideeffect "", "" ()
|
|
|
|
%incr = add i32 %counter, 1
|
|
%lc = icmp sge i32 %incr, 1000
|
|
br i1 %lc, label %out, label %loop_body
|
|
|
|
out:
|
|
ret void
|
|
}
|
|
|
|
attributes #0 = { "ShaderType"="0" }
|
|
attributes #1 = { nounwind readonly }
|