File: loop-strength-reduce-loop-invar.ll

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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=riscv32 -verify-machineinstrs | FileCheck %s -check-prefixes=RV32
; RUN: llc < %s -mtriple=riscv64 -verify-machineinstrs | FileCheck %s -check-prefixes=RV64

; Test case:
; - `A[row]` is loop invariant and should be hoisted up to preheader
; FIXME: RV32 is working as expected, but RV64 doesn't

; The following LLVM IR simulates:
; int A[16][16];
; void test(int row, int N) {
; 	for (int i=0; i<N; ++I) {
; 		A[row][i+1] = 4;
; 		A[row][i+2] = 5;
; 	}
; }

; After LSR:
; int A[16][16];
; void test(int row, int N) {
; 	for (int *ptr = A[row][2]; N>0; N--) {
; 		*(ptr-1) = 4;
; 		*(ptr) = 5;
; 		++ptr;
; 	}
; }

@A = internal global [16 x [16 x i32]] zeroinitializer, align 32		; <ptr> [#uses=2]

define void @test(i32 signext %row, i32 signext %N.in) nounwind {
; RV32-LABEL: test:
; RV32:       # %bb.0: # %entry
; RV32-NEXT:    blez a1, .LBB0_3
; RV32-NEXT:  # %bb.1: # %cond_true.preheader
; RV32-NEXT:    slli a0, a0, 6
; RV32-NEXT:    lui a2, %hi(A)
; RV32-NEXT:    addi a2, a2, %lo(A)
; RV32-NEXT:    add a0, a0, a2
; RV32-NEXT:    addi a0, a0, 8
; RV32-NEXT:    li a2, 4
; RV32-NEXT:    li a3, 5
; RV32-NEXT:  .LBB0_2: # %cond_true
; RV32-NEXT:    # =>This Inner Loop Header: Depth=1
; RV32-NEXT:    sw a2, -4(a0)
; RV32-NEXT:    sw a3, 0(a0)
; RV32-NEXT:    addi a1, a1, -1
; RV32-NEXT:    addi a0, a0, 4
; RV32-NEXT:    bnez a1, .LBB0_2
; RV32-NEXT:  .LBB0_3: # %return
; RV32-NEXT:    ret
;
; RV64-LABEL: test:
; RV64:       # %bb.0: # %entry
; RV64-NEXT:    blez a1, .LBB0_3
; RV64-NEXT:  # %bb.1: # %cond_true.preheader
; RV64-NEXT:    negw a1, a1
; RV64-NEXT:    slli a0, a0, 6
; RV64-NEXT:    lui a2, %hi(A)
; RV64-NEXT:    addi a2, a2, %lo(A)
; RV64-NEXT:    add a0, a0, a2
; RV64-NEXT:    addi a2, a0, 4
; RV64-NEXT:    li a3, 2
; RV64-NEXT:    li a4, 4
; RV64-NEXT:    li a5, 5
; RV64-NEXT:    li a6, 2
; RV64-NEXT:  .LBB0_2: # %cond_true
; RV64-NEXT:    # =>This Inner Loop Header: Depth=1
; RV64-NEXT:    sw a4, 0(a2)
; RV64-NEXT:    slli a7, a6, 2
; RV64-NEXT:    add a7, a0, a7
; RV64-NEXT:    sw a5, 0(a7)
; RV64-NEXT:    addiw a6, a6, 1
; RV64-NEXT:    addw a7, a1, a6
; RV64-NEXT:    addi a2, a2, 4
; RV64-NEXT:    bne a7, a3, .LBB0_2
; RV64-NEXT:  .LBB0_3: # %return
; RV64-NEXT:    ret
entry:
	%N = bitcast i32 %N.in to i32
	%tmp5 = icmp sgt i32 %N.in, 0
	br i1 %tmp5, label %cond_true, label %return

cond_true:
	%indvar = phi i32 [ 0, %entry ], [ %indvar.next, %cond_true ]
	%tmp2 = add i32 %indvar, 1
	%tmp = getelementptr [16 x [16 x i32]], ptr @A, i32 0, i32 %row, i32 %tmp2
	store i32 4, ptr %tmp
	%tmp5.upgrd.1 = add i32 %indvar, 2
	%tmp7 = getelementptr [16 x [16 x i32]], ptr @A, i32 0, i32 %row, i32 %tmp5.upgrd.1
	store i32 5, ptr %tmp7
	%indvar.next = add i32 %indvar, 1
	%exitcond = icmp eq i32 %indvar.next, %N
	br i1 %exitcond, label %return, label %cond_true

return:
	ret void
}