Philip Reames 20cbb6cdf8 [LoopPred] Selectively disable to preserve test cases
I'm about to enable the new loop predication transform by default.  It has the effect of completely destroying many read only loops - which happen to be a super common idiom in our test cases.  So as to preserve test coverage of other transforms, disable the new transform where it would cause sharp test coverage regressions.

(This is semantically part of the enabling commit.  It's committed separate to ease revert if the actual flag flip gets reverted.)
2019-11-06 15:41:57 -08:00

203 lines
8.2 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -indvars -indvars-predicate-loops=0 < %s | FileCheck %s
define i16 @constant() {
; CHECK-LABEL: @constant(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP1:%.*]]
; CHECK: loop1:
; CHECK-NEXT: [[L1:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[L1_ADD:%.*]], [[LOOP1]] ]
; CHECK-NEXT: [[L1_ADD]] = add nuw nsw i16 [[L1]], 1
; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i16 [[L1_ADD]], 2
; CHECK-NEXT: br i1 [[CMP1]], label [[LOOP1]], label [[LOOP2_PREHEADER:%.*]]
; CHECK: loop2.preheader:
; CHECK-NEXT: br label [[LOOP2:%.*]]
; CHECK: loop2:
; CHECK-NEXT: [[K2:%.*]] = phi i16 [ [[K2_ADD:%.*]], [[LOOP2]] ], [ 182, [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2:%.*]] = phi i16 [ [[L2_ADD:%.*]], [[LOOP2]] ], [ 0, [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2_ADD]] = add nuw nsw i16 [[L2]], 1
; CHECK-NEXT: tail call void @foo(i16 [[K2]])
; CHECK-NEXT: [[K2_ADD]] = add nuw nsw i16 [[K2]], 1
; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i16 [[L2_ADD]], 2
; CHECK-NEXT: br i1 [[CMP2]], label [[LOOP2]], label [[LOOP2_END:%.*]]
; CHECK: loop2.end:
; CHECK-NEXT: ret i16 184
;
entry:
br label %loop1
loop1: ; preds = %entry, %loop1
%k1 = phi i16 [ 180, %entry ], [ %k1.add, %loop1 ]
%l1 = phi i16 [ 0, %entry ], [ %l1.add, %loop1 ]
%k1.add = add nuw nsw i16 %k1, 1
%l1.add = add nuw nsw i16 %l1, 1
%cmp1 = icmp ult i16 %l1.add, 2
br i1 %cmp1, label %loop1, label %loop2.preheader
loop2.preheader: ; preds = %loop1
%k1.add.lcssa = phi i16 [ %k1.add, %loop1 ]
br label %loop2
loop2: ; preds = %loop2.preheader, %loop2
%k2 = phi i16 [ %k2.add, %loop2 ], [ %k1.add.lcssa, %loop2.preheader ]
%l2 = phi i16 [ %l2.add, %loop2 ], [ 0, %loop2.preheader ]
%l2.add = add nuw i16 %l2, 1
tail call void @foo(i16 %k2)
%k2.add = add nuw nsw i16 %k2, 1
%cmp2 = icmp ult i16 %l2.add, 2
br i1 %cmp2, label %loop2, label %loop2.end
loop2.end: ; preds = %loop2
%k2.add.lcssa = phi i16 [ %k2.add, %loop2 ]
ret i16 %k2.add.lcssa
}
define i16 @dom_argument(i16 %arg1, i16 %arg2) {
; CHECK-LABEL: @dom_argument(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP1:%.*]]
; CHECK: loop1:
; CHECK-NEXT: [[L1:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[L1_ADD:%.*]], [[LOOP1]] ]
; CHECK-NEXT: [[L1_ADD]] = add nuw nsw i16 [[L1]], 1
; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i16 [[L1_ADD]], 2
; CHECK-NEXT: br i1 [[CMP1]], label [[LOOP1]], label [[LOOP2_PREHEADER:%.*]]
; CHECK: loop2.preheader:
; CHECK-NEXT: br label [[LOOP2:%.*]]
; CHECK: loop2:
; CHECK-NEXT: [[K2:%.*]] = phi i16 [ [[K2_ADD:%.*]], [[LOOP2]] ], [ [[ARG2:%.*]], [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2:%.*]] = phi i16 [ [[L2_ADD:%.*]], [[LOOP2]] ], [ 0, [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2_ADD]] = add nuw nsw i16 [[L2]], 1
; CHECK-NEXT: tail call void @foo(i16 [[K2]])
; CHECK-NEXT: [[K2_ADD]] = add nuw nsw i16 [[K2]], 1
; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i16 [[L2_ADD]], 2
; CHECK-NEXT: br i1 [[CMP2]], label [[LOOP2]], label [[LOOP2_END:%.*]]
; CHECK: loop2.end:
; CHECK-NEXT: [[K2_ADD_LCSSA:%.*]] = phi i16 [ [[K2_ADD]], [[LOOP2]] ]
; CHECK-NEXT: ret i16 [[K2_ADD_LCSSA]]
;
entry:
br label %loop1
loop1: ; preds = %entry, %loop1
%k1 = phi i16 [ 100, %entry ], [ %k1.add, %loop1 ]
%l1 = phi i16 [ 0, %entry ], [ %l1.add, %loop1 ]
%selector = phi i16 [ %arg1, %entry ], [ %arg2, %loop1 ]
%k1.add = add nuw nsw i16 %k1, 1
%l1.add = add nuw nsw i16 %l1, 1
%cmp1 = icmp ult i16 %l1.add, 2
br i1 %cmp1, label %loop1, label %loop2.preheader
loop2.preheader: ; preds = %loop1
%k1.add.lcssa = phi i16 [ %selector, %loop1 ]
br label %loop2
loop2: ; preds = %loop2.preheader, %loop2
%k2 = phi i16 [ %k2.add, %loop2 ], [ %k1.add.lcssa, %loop2.preheader ]
%l2 = phi i16 [ %l2.add, %loop2 ], [ 0, %loop2.preheader ]
%l2.add = add nuw i16 %l2, 1
tail call void @foo(i16 %k2)
%k2.add = add nuw nsw i16 %k2, 1
%cmp2 = icmp ult i16 %l2.add, 2
br i1 %cmp2, label %loop2, label %loop2.end
loop2.end: ; preds = %loop2
%k2.add.lcssa = phi i16 [ %k2.add, %loop2 ]
ret i16 %k2.add.lcssa
}
define i16 @dummy_phi_outside_loop(i16 %arg) {
; CHECK-LABEL: @dummy_phi_outside_loop(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP2_PREHEADER:%.*]]
; CHECK: loop2.preheader:
; CHECK-NEXT: [[DUMMY:%.*]] = phi i16 [ [[ARG:%.*]], [[ENTRY:%.*]] ]
; CHECK-NEXT: br label [[LOOP2:%.*]]
; CHECK: loop2:
; CHECK-NEXT: [[K2:%.*]] = phi i16 [ [[K2_ADD:%.*]], [[LOOP2]] ], [ [[DUMMY]], [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2:%.*]] = phi i16 [ [[L2_ADD:%.*]], [[LOOP2]] ], [ 0, [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2_ADD]] = add nuw nsw i16 [[L2]], 1
; CHECK-NEXT: tail call void @foo(i16 [[K2]])
; CHECK-NEXT: [[K2_ADD]] = add nuw nsw i16 [[K2]], 1
; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i16 [[L2_ADD]], 2
; CHECK-NEXT: br i1 [[CMP2]], label [[LOOP2]], label [[LOOP2_END:%.*]]
; CHECK: loop2.end:
; CHECK-NEXT: [[K2_ADD_LCSSA:%.*]] = phi i16 [ [[K2_ADD]], [[LOOP2]] ]
; CHECK-NEXT: ret i16 [[K2_ADD_LCSSA]]
;
entry:
br label %loop2.preheader
loop2.preheader: ; preds = %loop1
%dummy = phi i16 [ %arg, %entry ]
br label %loop2
loop2: ; preds = %loop2.preheader, %loop2
%k2 = phi i16 [ %k2.add, %loop2 ], [ %dummy, %loop2.preheader ]
%l2 = phi i16 [ %l2.add, %loop2 ], [ 0, %loop2.preheader ]
%l2.add = add nuw i16 %l2, 1
tail call void @foo(i16 %k2)
%k2.add = add nuw nsw i16 %k2, 1
%cmp2 = icmp ult i16 %l2.add, 2
br i1 %cmp2, label %loop2, label %loop2.end
loop2.end: ; preds = %loop2
%k2.add.lcssa = phi i16 [ %k2.add, %loop2 ]
ret i16 %k2.add.lcssa
}
define i16 @neg_loop_carried(i16 %arg) {
; CHECK-LABEL: @neg_loop_carried(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP1:%.*]]
; CHECK: loop1:
; CHECK-NEXT: [[L1:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[L1_ADD:%.*]], [[LOOP1]] ]
; CHECK-NEXT: [[L1_ADD]] = add nuw nsw i16 [[L1]], 1
; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i16 [[L1_ADD]], 2
; CHECK-NEXT: br i1 [[CMP1]], label [[LOOP1]], label [[LOOP2_PREHEADER:%.*]]
; CHECK: loop2.preheader:
; CHECK-NEXT: [[TMP0:%.*]] = add i16 [[ARG:%.*]], 2
; CHECK-NEXT: br label [[LOOP2:%.*]]
; CHECK: loop2:
; CHECK-NEXT: [[K2:%.*]] = phi i16 [ [[K2_ADD:%.*]], [[LOOP2]] ], [ [[TMP0]], [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2:%.*]] = phi i16 [ [[L2_ADD:%.*]], [[LOOP2]] ], [ 0, [[LOOP2_PREHEADER]] ]
; CHECK-NEXT: [[L2_ADD]] = add nuw nsw i16 [[L2]], 1
; CHECK-NEXT: tail call void @foo(i16 [[K2]])
; CHECK-NEXT: [[K2_ADD]] = add nuw nsw i16 [[K2]], 1
; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i16 [[L2_ADD]], 2
; CHECK-NEXT: br i1 [[CMP2]], label [[LOOP2]], label [[LOOP2_END:%.*]]
; CHECK: loop2.end:
; CHECK-NEXT: [[K2_ADD_LCSSA:%.*]] = phi i16 [ [[K2_ADD]], [[LOOP2]] ]
; CHECK-NEXT: ret i16 [[K2_ADD_LCSSA]]
;
entry:
br label %loop1
loop1: ; preds = %entry, %loop1
%k1 = phi i16 [ %arg, %entry ], [ %k1.add, %loop1 ]
%l1 = phi i16 [ 0, %entry ], [ %l1.add, %loop1 ]
%k1.add = add nuw nsw i16 %k1, 1
%l1.add = add nuw nsw i16 %l1, 1
%cmp1 = icmp ult i16 %l1.add, 2
br i1 %cmp1, label %loop1, label %loop2.preheader
loop2.preheader: ; preds = %loop1
%k1.add.lcssa = phi i16 [ %k1.add, %loop1 ]
br label %loop2
loop2: ; preds = %loop2.preheader, %loop2
%k2 = phi i16 [ %k2.add, %loop2 ], [ %k1.add.lcssa, %loop2.preheader ]
%l2 = phi i16 [ %l2.add, %loop2 ], [ 0, %loop2.preheader ]
%l2.add = add nuw i16 %l2, 1
tail call void @foo(i16 %k2)
%k2.add = add nuw nsw i16 %k2, 1
%cmp2 = icmp ult i16 %l2.add, 2
br i1 %cmp2, label %loop2, label %loop2.end
loop2.end: ; preds = %loop2
%k2.add.lcssa = phi i16 [ %k2.add, %loop2 ]
ret i16 %k2.add.lcssa
}
declare void @foo(i16)