[RISCV] Add test/CodeGen/RISCV/lsr-legaladdimm.ll

Add a test case which will show a codegen difference upon the implementation 
of a target-specific isLegalAddImmediate.

llvm-svn: 330936
This commit is contained in:
Alex Bradbury 2018-04-26 12:57:29 +00:00
parent 38fe227fd9
commit c2f78f80da
1 changed files with 49 additions and 0 deletions

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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -mtriple=riscv32 -verify-machineinstrs < %s \
; RUN: | FileCheck %s -check-prefix=RV32I
@a = global [4096 x i32] zeroinitializer, align 4
@b = global [4096 x i32] zeroinitializer, align 4
; This test demonstrates very slightly improved codegen in the case that
; a correct isLegalAddImmediate is implemented, thanks to LoopStrengthReduce.
define i32 @main() nounwind {
; RV32I-LABEL: main:
; RV32I: # %bb.0: # %entry
; RV32I-NEXT: addi a0, zero, -2048
; RV32I-NEXT: lui a1, %hi(b)
; RV32I-NEXT: addi a1, a1, %lo(b)
; RV32I-NEXT: lui a2, %hi(a)
; RV32I-NEXT: addi a2, a2, %lo(a)
; RV32I-NEXT: lui a3, 1
; RV32I-NEXT: addi a3, a3, -2048
; RV32I-NEXT: .LBB0_1: # %for.body
; RV32I-NEXT: # =>This Inner Loop Header: Depth=1
; RV32I-NEXT: sw a0, 0(a2)
; RV32I-NEXT: add a4, a0, a3
; RV32I-NEXT: sw a4, 0(a1)
; RV32I-NEXT: addi a2, a2, 4
; RV32I-NEXT: addi a1, a1, 4
; RV32I-NEXT: addi a0, a0, 1
; RV32I-NEXT: bne a0, a3, .LBB0_1
; RV32I-NEXT: # %bb.2: # %for.end
; RV32I-NEXT: mv a0, zero
; RV32I-NEXT: ret
entry:
br label %for.body
for.body:
%i.08 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
%sub = add nsw i32 %i.08, -2048
%arrayidx = getelementptr inbounds [4096 x i32], [4096 x i32]* @a, i32 0, i32 %i.08
store i32 %sub, i32* %arrayidx, align 4
%arrayidx1 = getelementptr inbounds [4096 x i32], [4096 x i32]* @b, i32 0, i32 %i.08
store i32 %i.08, i32* %arrayidx1, align 4
%inc = add nuw nsw i32 %i.08, 1
%exitcond = icmp eq i32 %inc, 4096
br i1 %exitcond, label %for.end, label %for.body
for.end:
ret i32 0
}