Index: llvm/include/llvm/IR/Intrinsics.td =================================================================== --- llvm/include/llvm/IR/Intrinsics.td +++ llvm/include/llvm/IR/Intrinsics.td @@ -1070,7 +1070,7 @@ // Supports widenable conditions for guards represented as explicit branches. def int_experimental_widenable_condition : Intrinsic<[llvm_i1_ty], [], - [IntrInaccessibleMemOnly, IntrWillReturn]>; + [IntrInaccessibleMemOnly, IntrWillReturn, IntrSpeculatable]>; // NOP: calls/invokes to this intrinsic are removed by codegen def int_donothing : Intrinsic<[], [], [IntrNoMem, IntrWillReturn]>; Index: llvm/lib/Transforms/Scalar/LICM.cpp =================================================================== --- llvm/lib/Transforms/Scalar/LICM.cpp +++ llvm/lib/Transforms/Scalar/LICM.cpp @@ -1144,6 +1144,10 @@ // Assumes don't actually alias anything or throw return true; + if (match(CI, m_Intrinsic())) + // Widenable conditions don't actually alias anything or throw + return true; + // Handle simple cases by querying alias analysis. FunctionModRefBehavior Behavior = AA->getModRefBehavior(CI); if (Behavior == FMRB_DoesNotAccessMemory) Index: llvm/test/Transforms/LICM/explicit_guards.ll =================================================================== --- llvm/test/Transforms/LICM/explicit_guards.ll +++ llvm/test/Transforms/LICM/explicit_guards.ll @@ -2,21 +2,54 @@ ; RUN: opt -S -make-guards-explicit -basicaa -licm < %s | FileCheck %s ; RUN: opt -S -aa-pipeline=basic-aa -passes='require,make-guards-explicit,loop(licm)' < %s | FileCheck %s -; Test interaction between explicit guards and LICM: make sure that we do not -; hoist explicit conditions while we can hoist invariant loads in presence of -; explicit guards. - declare void @llvm.experimental.guard(i1,...) +declare void @maythrow() ; Make sure that we do not hoist widenable_cond out of loop. -define void @do_not_hoist_widenable_cond(i1 %cond, i32 %N, i32 %M) { -; CHECK-LABEL: @do_not_hoist_widenable_cond( +define void @hoist_widenable_cond(i1 %cond, i32 %N, i32 %M) { +; CHECK-LABEL: @hoist_widenable_cond( ; CHECK-NEXT: entry: +; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition() ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[GUARDED:%.*]] ] ; CHECK-NEXT: [[GUARD_COND:%.*]] = icmp slt i32 [[IV]], [[N:%.*]] +; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[GUARD_COND]], [[WIDENABLE_COND]] +; CHECK-NEXT: br i1 [[EXIPLICIT_GUARD_COND]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 +; CHECK: deopt: +; CHECK-NEXT: call void (...) @llvm.experimental.deoptimize.isVoid() [ "deopt"() ] +; CHECK-NEXT: ret void +; CHECK: guarded: +; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV]], [[M:%.*]] +; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1 +; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ] + %guard_cond = icmp slt i32 %iv, %N + call void(i1, ...) @llvm.experimental.guard(i1 %guard_cond) [ "deopt"() ] + %loop_cond = icmp slt i32 %iv, %M + %iv.next = add i32 %iv, 1 + br i1 %loop_cond, label %loop, label %exit + +exit: + ret void +} + +define void @hoist_widenable_cond_speculate(i1 %cond, i32 %N, i32 %M) { +; CHECK-LABEL: @hoist_widenable_cond_speculate( +; CHECK-NEXT: entry: ; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition() +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[GUARDED:%.*]] ] +; CHECK-NEXT: [[GUARD_COND:%.*]] = icmp slt i32 [[IV]], [[N:%.*]] +; CHECK-NEXT: call void @maythrow() ; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[GUARD_COND]], [[WIDENABLE_COND]] ; CHECK-NEXT: br i1 [[EXIPLICIT_GUARD_COND]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: @@ -35,6 +68,7 @@ loop: %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ] %guard_cond = icmp slt i32 %iv, %N + call void @maythrow() call void(i1, ...) @llvm.experimental.guard(i1 %guard_cond) [ "deopt"() ] %loop_cond = icmp slt i32 %iv, %M %iv.next = add i32 %iv, 1 @@ -44,15 +78,16 @@ ret void } + define void @hoist_invariant_load(i1 %cond, i32* %np, i32 %M) { ; CHECK-LABEL: @hoist_invariant_load( ; CHECK-NEXT: entry: ; CHECK-NEXT: [[N:%.*]] = load i32, i32* [[NP:%.*]] +; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition() ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[GUARDED:%.*]] ] ; CHECK-NEXT: [[GUARD_COND:%.*]] = icmp slt i32 [[IV]], [[N]] -; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition() ; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[GUARD_COND]], [[WIDENABLE_COND]] ; CHECK-NEXT: br i1 [[EXIPLICIT_GUARD_COND]], label [[GUARDED]], label [[DEOPT:%.*]], !prof !0 ; CHECK: deopt: