1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 11:13:28 +01:00

[Test] Add tests demonstrating missing case of usub with overflow usage

The test shows how "usub with overflow" opt gets or does not get applied
to increment of IV depending on its code placement, while two cases are
semantically equivalent.
This commit is contained in:
Max Kazantsev 2021-02-05 18:27:42 +07:00
parent 515379758b
commit 78987b1311

View File

@ -0,0 +1,96 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -mtriple=x86_64-linux -codegenprepare -S < %s | FileCheck %s
define i32 @test_01(i32* %p, i64 %len, i32 %x) {
; CHECK-LABEL: @test_01(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[MATH:%.*]], [[BACKEDGE:%.*]] ], [ [[LEN:%.*]], [[ENTRY:%.*]] ]
; CHECK-NEXT: [[TMP0:%.*]] = call { i64, i1 } @llvm.usub.with.overflow.i64(i64 [[IV]], i64 1)
; CHECK-NEXT: [[MATH]] = extractvalue { i64, i1 } [[TMP0]], 0
; CHECK-NEXT: [[OV:%.*]] = extractvalue { i64, i1 } [[TMP0]], 1
; CHECK-NEXT: br i1 [[OV]], label [[EXIT:%.*]], label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[SUNKADDR:%.*]] = mul i64 [[IV]], 4
; CHECK-NEXT: [[TMP1:%.*]] = bitcast i32* [[P:%.*]] to i8*
; CHECK-NEXT: [[SUNKADDR1:%.*]] = getelementptr i8, i8* [[TMP1]], i64 [[SUNKADDR]]
; CHECK-NEXT: [[SUNKADDR2:%.*]] = getelementptr i8, i8* [[SUNKADDR1]], i64 -4
; CHECK-NEXT: [[TMP2:%.*]] = bitcast i8* [[SUNKADDR2]] to i32*
; CHECK-NEXT: [[LOADED:%.*]] = load atomic i32, i32* [[TMP2]] unordered, align 4
; CHECK-NEXT: [[COND_2:%.*]] = icmp eq i32 [[LOADED]], [[X:%.*]]
; CHECK-NEXT: br i1 [[COND_2]], label [[FAILURE:%.*]], label [[LOOP]]
; CHECK: exit:
; CHECK-NEXT: ret i32 -1
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%scevgep = getelementptr i32, i32* %p, i64 -1
br label %loop
loop: ; preds = %backedge, %entry
%iv = phi i64 [ %iv.next, %backedge ], [ %len, %entry ]
%iv.next = add i64 %iv, -1
%cond_1 = icmp eq i64 %iv, 0
br i1 %cond_1, label %exit, label %backedge
backedge: ; preds = %loop
%scevgep1 = getelementptr i32, i32* %scevgep, i64 %iv
%loaded = load atomic i32, i32* %scevgep1 unordered, align 4
%cond_2 = icmp eq i32 %loaded, %x
br i1 %cond_2, label %failure, label %loop
exit: ; preds = %loop
ret i32 -1
failure: ; preds = %backedge
unreachable
}
; TODO: We can use trick with usub here.
define i32 @test_02(i32* %p, i64 %len, i32 %x) {
; CHECK-LABEL: @test_02(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i64 [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ], [ [[LEN:%.*]], [[ENTRY:%.*]] ]
; CHECK-NEXT: [[COND_1:%.*]] = icmp eq i64 [[IV]], 0
; CHECK-NEXT: br i1 [[COND_1]], label [[EXIT:%.*]], label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[SUNKADDR:%.*]] = mul i64 [[IV]], 4
; CHECK-NEXT: [[TMP0:%.*]] = bitcast i32* [[P:%.*]] to i8*
; CHECK-NEXT: [[SUNKADDR1:%.*]] = getelementptr i8, i8* [[TMP0]], i64 [[SUNKADDR]]
; CHECK-NEXT: [[SUNKADDR2:%.*]] = getelementptr i8, i8* [[SUNKADDR1]], i64 -4
; CHECK-NEXT: [[TMP1:%.*]] = bitcast i8* [[SUNKADDR2]] to i32*
; CHECK-NEXT: [[LOADED:%.*]] = load atomic i32, i32* [[TMP1]] unordered, align 4
; CHECK-NEXT: [[COND_2:%.*]] = icmp eq i32 [[LOADED]], [[X:%.*]]
; CHECK-NEXT: [[IV_NEXT]] = add i64 [[IV]], -1
; CHECK-NEXT: br i1 [[COND_2]], label [[FAILURE:%.*]], label [[LOOP]]
; CHECK: exit:
; CHECK-NEXT: ret i32 -1
; CHECK: failure:
; CHECK-NEXT: unreachable
;
entry:
%scevgep = getelementptr i32, i32* %p, i64 -1
br label %loop
loop: ; preds = %backedge, %entry
%iv = phi i64 [ %iv.next, %backedge ], [ %len, %entry ]
%cond_1 = icmp eq i64 %iv, 0
br i1 %cond_1, label %exit, label %backedge
backedge: ; preds = %loop
%scevgep1 = getelementptr i32, i32* %scevgep, i64 %iv
%loaded = load atomic i32, i32* %scevgep1 unordered, align 4
%cond_2 = icmp eq i32 %loaded, %x
%iv.next = add i64 %iv, -1
br i1 %cond_2, label %failure, label %loop
exit: ; preds = %loop
ret i32 -1
failure: ; preds = %backedge
unreachable
}