maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[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 ef9e1e5a59
commit 78935ea1e7
1 changed files with 96 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

96
llvm/test/CodeGen/X86/usub_inc_iv.ll Normal file
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
}