llvm/test/CodeGen/Lanai/subword.ll
Jacques Pienaar f38ea34724 [lanai] Add subword scheduling itineraries.
Differentiate between word and subword memory operations as they take different
amount of cycles to complete. This just adds a basic model of the subword
latency to the scheduler.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266898 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-20 18:28:55 +00:00

30 lines
905 B
LLVM

; RUN: llc < %s -mtriple=lanai-unknown-unknown | FileCheck %s
; Test scheduling of subwords.
%struct.X = type { i16, i16 }
define void @f(%struct.X* inreg nocapture %c) #0 {
entry:
%a = getelementptr inbounds %struct.X, %struct.X* %c, i32 0, i32 0
%0 = load i16, i16* %a, align 2
%inc = add i16 %0, 1
store i16 %inc, i16* %a, align 2
%b = getelementptr inbounds %struct.X, %struct.X* %c, i32 0, i32 1
%1 = load i16, i16* %b, align 2
%dec = add i16 %1, -1
store i16 %dec, i16* %b, align 2
ret void
}
; Verify that the two loads occur before the stores. Without memory
; disambiguation and subword schedule, the resultant code was a per subword
; load-modify-store sequence instead of the more optimal schedule where all
; loads occurred before modification and storage.
; CHECK: uld.h
; CHECK-NEXT: uld.h
; CHECK-NEXT: add
; CHECK-NEXT: st.h
; CHECK-NEXT: sub
; CHECK-NEXT: st.h