; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -S -loop-predication-skip-profitability-checks=false -passes='require<scalar-evolution>,loop-mssa(loop-predication)' -verify-memoryssa < %s 2>&1 | FileCheck %s ; latch block exits to a speculation block. We account for this since deopt is ; very rarely taken. So we do not predicate this loop using that coarse latch ; check. ; LatchExitProbability: 0x04000000 / 0x80000000 = 3.12% ; ExitingBlockProbability: 0x7ffa572a / 0x80000000 = 99.98% define i64 @donot_predicate(i64* nocapture readonly %arg, i32 %length, i64* nocapture readonly %arg2, i64* nocapture readonly %n_addr, i64 %i) !prof !21 { ; CHECK-LABEL: @donot_predicate( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[LENGTH_EXT:%.*]] = zext i32 [[LENGTH:%.*]] to i64 ; CHECK-NEXT: [[N_PRE:%.*]] = load i64, i64* [[N_ADDR:%.*]], align 4 ; CHECK-NEXT: br label [[HEADER:%.*]] ; CHECK: Header: ; CHECK-NEXT: [[RESULT_IN3:%.*]] = phi i64* [ [[ARG2:%.*]], [[ENTRY:%.*]] ], [ [[ARG:%.*]], [[LATCH:%.*]] ] ; CHECK-NEXT: [[J2:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[J_NEXT:%.*]], [[LATCH]] ] ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i64 [[J2]], [[LENGTH_EXT]] ; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 [[WITHIN_BOUNDS]], i32 9) [ "deopt"() ] ; CHECK-NEXT: [[INNERCMP:%.*]] = icmp eq i64 [[J2]], [[N_PRE]] ; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i64 [[J2]], 1 ; CHECK-NEXT: br i1 [[INNERCMP]], label [[LATCH]], label [[EXIT:%.*]], !prof [[PROF1:![0-9]+]] ; CHECK: Latch: ; CHECK-NEXT: [[SPECULATE_TRIP_COUNT:%.*]] = icmp ult i64 [[J_NEXT]], 1048576 ; CHECK-NEXT: br i1 [[SPECULATE_TRIP_COUNT]], label [[HEADER]], label [[DEOPT:%.*]] ; CHECK: deopt: ; CHECK-NEXT: [[COUNTED_SPECULATION_FAILED:%.*]] = call i64 (...) @llvm.experimental.deoptimize.i64(i64 30) [ "deopt"(i32 0) ] ; CHECK-NEXT: ret i64 [[COUNTED_SPECULATION_FAILED]] ; CHECK: exit: ; CHECK-NEXT: [[RESULT_IN3_LCSSA:%.*]] = phi i64* [ [[RESULT_IN3]], [[HEADER]] ] ; CHECK-NEXT: [[RESULT_LE:%.*]] = load i64, i64* [[RESULT_IN3_LCSSA]], align 8 ; CHECK-NEXT: ret i64 [[RESULT_LE]] ; entry: %length.ext = zext i32 %length to i64 %n.pre = load i64, i64* %n_addr, align 4 br label %Header Header: ; preds = %entry, %Latch %result.in3 = phi i64* [ %arg2, %entry ], [ %arg, %Latch ] %j2 = phi i64 [ 0, %entry ], [ %j.next, %Latch ] %within.bounds = icmp ult i64 %j2, %length.ext call void (i1, ...) @llvm.experimental.guard(i1 %within.bounds, i32 9) [ "deopt"() ] %innercmp = icmp eq i64 %j2, %n.pre %j.next = add nuw nsw i64 %j2, 1 br i1 %innercmp, label %Latch, label %exit, !prof !0 Latch: ; preds = %Header %speculate_trip_count = icmp ult i64 %j.next, 1048576 br i1 %speculate_trip_count, label %Header, label %deopt deopt: ; preds = %Latch %counted_speculation_failed = call i64 (...) @llvm.experimental.deoptimize.i64(i64 30) [ "deopt"(i32 0) ] ret i64 %counted_speculation_failed exit: ; preds = %Header %result.in3.lcssa = phi i64* [ %result.in3, %Header ] %result.le = load i64, i64* %result.in3.lcssa, align 8 ret i64 %result.le } !0 = !{!"branch_weights", i32 18, i32 104200} ; predicate loop since there's no profile information and BPI concluded all ; exiting blocks have same probability of exiting from loop. define i64 @predicate(i64* nocapture readonly %arg, i32 %length, i64* nocapture readonly %arg2, i64* nocapture readonly %n_addr, i64 %i) !prof !21 { ; CHECK-LABEL: @predicate( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[LENGTH_EXT:%.*]] = zext i32 [[LENGTH:%.*]] to i64 ; CHECK-NEXT: [[N_PRE:%.*]] = load i64, i64* [[N_ADDR:%.*]], align 4 ; CHECK-NEXT: [[TMP0:%.*]] = icmp ule i64 1048576, [[LENGTH_EXT]] ; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i64 0, [[LENGTH_EXT]] ; CHECK-NEXT: [[TMP2:%.*]] = and i1 [[TMP1]], [[TMP0]] ; CHECK-NEXT: br label [[HEADER:%.*]] ; CHECK: Header: ; CHECK-NEXT: [[RESULT_IN3:%.*]] = phi i64* [ [[ARG2:%.*]], [[ENTRY:%.*]] ], [ [[ARG:%.*]], [[LATCH:%.*]] ] ; CHECK-NEXT: [[J2:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[J_NEXT:%.*]], [[LATCH]] ] ; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 [[TMP2]], i32 9) [ "deopt"() ] ; CHECK-NEXT: [[INNERCMP:%.*]] = icmp eq i64 [[J2]], [[N_PRE]] ; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i64 [[J2]], 1 ; CHECK-NEXT: br i1 [[INNERCMP]], label [[LATCH]], label [[EXIT:%.*]] ; CHECK: Latch: ; CHECK-NEXT: [[SPECULATE_TRIP_COUNT:%.*]] = icmp ult i64 [[J_NEXT]], 1048576 ; CHECK-NEXT: br i1 [[SPECULATE_TRIP_COUNT]], label [[HEADER]], label [[EXITLATCH:%.*]] ; CHECK: exitLatch: ; CHECK-NEXT: ret i64 1 ; CHECK: exit: ; CHECK-NEXT: [[RESULT_IN3_LCSSA:%.*]] = phi i64* [ [[RESULT_IN3]], [[HEADER]] ] ; CHECK-NEXT: [[RESULT_LE:%.*]] = load i64, i64* [[RESULT_IN3_LCSSA]], align 8 ; CHECK-NEXT: ret i64 [[RESULT_LE]] ; entry: %length.ext = zext i32 %length to i64 %n.pre = load i64, i64* %n_addr, align 4 br label %Header Header: ; preds = %entry, %Latch %result.in3 = phi i64* [ %arg2, %entry ], [ %arg, %Latch ] %j2 = phi i64 [ 0, %entry ], [ %j.next, %Latch ] %within.bounds = icmp ult i64 %j2, %length.ext call void (i1, ...) @llvm.experimental.guard(i1 %within.bounds, i32 9) [ "deopt"() ] %innercmp = icmp eq i64 %j2, %n.pre %j.next = add nuw nsw i64 %j2, 1 br i1 %innercmp, label %Latch, label %exit Latch: ; preds = %Header %speculate_trip_count = icmp ult i64 %j.next, 1048576 br i1 %speculate_trip_count, label %Header, label %exitLatch exitLatch: ; preds = %Latch ret i64 1 exit: ; preds = %Header %result.in3.lcssa = phi i64* [ %result.in3, %Header ] %result.le = load i64, i64* %result.in3.lcssa, align 8 ret i64 %result.le } ; Same as test above but with profiling data that the most probable exit from ; the loop is the header exiting block (not the latch block). So do not predicate. ; LatchExitProbability: 0x000020e1 / 0x80000000 = 0.00% ; ExitingBlockProbability: 0x7ffcbb86 / 0x80000000 = 99.99% define i64 @donot_predicate_prof(i64* nocapture readonly %arg, i32 %length, i64* nocapture readonly %arg2, i64* nocapture readonly %n_addr, i64 %i) !prof !21 { ; CHECK-LABEL: @donot_predicate_prof( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[LENGTH_EXT:%.*]] = zext i32 [[LENGTH:%.*]] to i64 ; CHECK-NEXT: [[N_PRE:%.*]] = load i64, i64* [[N_ADDR:%.*]], align 4 ; CHECK-NEXT: br label [[HEADER:%.*]] ; CHECK: Header: ; CHECK-NEXT: [[RESULT_IN3:%.*]] = phi i64* [ [[ARG2:%.*]], [[ENTRY:%.*]] ], [ [[ARG:%.*]], [[LATCH:%.*]] ] ; CHECK-NEXT: [[J2:%.*]] = phi i64 [ 0, [[ENTRY]] ], [ [[J_NEXT:%.*]], [[LATCH]] ] ; CHECK-NEXT: [[WITHIN_BOUNDS:%.*]] = icmp ult i64 [[J2]], [[LENGTH_EXT]] ; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 [[WITHIN_BOUNDS]], i32 9) [ "deopt"() ] ; CHECK-NEXT: [[INNERCMP:%.*]] = icmp eq i64 [[J2]], [[N_PRE]] ; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i64 [[J2]], 1 ; CHECK-NEXT: br i1 [[INNERCMP]], label [[LATCH]], label [[EXIT:%.*]], !prof [[PROF2:![0-9]+]] ; CHECK: Latch: ; CHECK-NEXT: [[SPECULATE_TRIP_COUNT:%.*]] = icmp ult i64 [[J_NEXT]], 1048576 ; CHECK-NEXT: br i1 [[SPECULATE_TRIP_COUNT]], label [[HEADER]], label [[EXITLATCH:%.*]], !prof [[PROF3:![0-9]+]] ; CHECK: exitLatch: ; CHECK-NEXT: ret i64 1 ; CHECK: exit: ; CHECK-NEXT: [[RESULT_IN3_LCSSA:%.*]] = phi i64* [ [[RESULT_IN3]], [[HEADER]] ] ; CHECK-NEXT: [[RESULT_LE:%.*]] = load i64, i64* [[RESULT_IN3_LCSSA]], align 8 ; CHECK-NEXT: ret i64 [[RESULT_LE]] ; entry: %length.ext = zext i32 %length to i64 %n.pre = load i64, i64* %n_addr, align 4 br label %Header Header: ; preds = %entry, %Latch %result.in3 = phi i64* [ %arg2, %entry ], [ %arg, %Latch ] %j2 = phi i64 [ 0, %entry ], [ %j.next, %Latch ] %within.bounds = icmp ult i64 %j2, %length.ext call void (i1, ...) @llvm.experimental.guard(i1 %within.bounds, i32 9) [ "deopt"() ] %innercmp = icmp eq i64 %j2, %n.pre %j.next = add nuw nsw i64 %j2, 1 br i1 %innercmp, label %Latch, label %exit, !prof !1 Latch: ; preds = %Header %speculate_trip_count = icmp ult i64 %j.next, 1048576 br i1 %speculate_trip_count, label %Header, label %exitLatch, !prof !2 exitLatch: ; preds = %Latch ret i64 1 exit: ; preds = %Header %result.in3.lcssa = phi i64* [ %result.in3, %Header ] %result.le = load i64, i64* %result.in3.lcssa, align 8 ret i64 %result.le } declare i64 @llvm.experimental.deoptimize.i64(...) declare void @llvm.experimental.guard(i1, ...) !1 = !{!"branch_weights", i32 104, i32 1042861} !2 = !{!"branch_weights", i32 255129, i32 1} !21 = !{!"function_entry_count", i64 20000}