diff --git a/llvm/lib/Transforms/Scalar/LowerGuardIntrinsic.cpp b/llvm/lib/Transforms/Scalar/LowerGuardIntrinsic.cpp index 7ba17069f426..ecc646a490b3 100644 --- a/llvm/lib/Transforms/Scalar/LowerGuardIntrinsic.cpp +++ b/llvm/lib/Transforms/Scalar/LowerGuardIntrinsic.cpp @@ -21,12 +21,18 @@ #include "llvm/IR/Instructions.h" #include "llvm/IR/Intrinsics.h" #include "llvm/IR/IRBuilder.h" +#include "llvm/IR/MDBuilder.h" #include "llvm/IR/Module.h" #include "llvm/Pass.h" #include "llvm/Transforms/Utils/BasicBlockUtils.h" using namespace llvm; +static cl::opt LikelyBranchWeight( + "guards-likely-branch-weight", cl::Hidden, cl::init(1 << 20), + cl::desc("The probability of a guard failing is assumed to be the " + "reciprocal of this value (default = 1 << 20)")); + namespace { struct LowerGuardIntrinsic : public FunctionPass { static char ID; @@ -59,6 +65,10 @@ static void MakeGuardControlFlowExplicit(Function *DeoptIntrinsic, if (auto *MD = CI->getMetadata(LLVMContext::MD_make_implicit)) CheckBI->setMetadata(LLVMContext::MD_make_implicit, MD); + MDBuilder MDB(CI->getContext()); + CheckBI->setMetadata(LLVMContext::MD_prof, + MDB.createBranchWeights(LikelyBranchWeight, 1)); + IRBuilder<> B(DeoptBlockTerm); auto *DeoptCall = B.CreateCall(DeoptIntrinsic, Args, {DeoptOB}, ""); diff --git a/llvm/test/Transforms/LowerGuardIntrinsic/basic.ll b/llvm/test/Transforms/LowerGuardIntrinsic/basic.ll index ade24eb7b22d..7c3584a774e1 100644 --- a/llvm/test/Transforms/LowerGuardIntrinsic/basic.ll +++ b/llvm/test/Transforms/LowerGuardIntrinsic/basic.ll @@ -9,7 +9,7 @@ define i8 @f_basic(i1* %c_ptr) { call void(i1, ...) @llvm.experimental.guard(i1 %c, i32 1) [ "deopt"(i32 1) ] ret i8 5 -; CHECK: br i1 %c, label %guarded, label %deopt +; CHECK: br i1 %c, label %guarded, label %deopt, !prof !0 ; CHECK: deopt: ; CHECK-NEXT: %deoptcall = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ "deopt"(i32 1) ] ; CHECK-NEXT: ret i8 %deoptcall @@ -24,7 +24,7 @@ define void @f_void_return_ty(i1* %c_ptr) { call void(i1, ...) @llvm.experimental.guard(i1 %c, i32 1) [ "deopt"() ] ret void -; CHECK: br i1 %c, label %guarded, label %deopt +; CHECK: br i1 %c, label %guarded, label %deopt, !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void (...) @llvm.experimental.deoptimize.isVoid(i32 1) [ "deopt"() ] ; CHECK-NEXT: ret void @@ -39,7 +39,7 @@ define void @f_multiple_args(i1* %c_ptr) { call void(i1, ...) @llvm.experimental.guard(i1 %c, i32 1, i32 2, double 500.0) [ "deopt"(i32 2, i32 3) ] ret void -; CHECK: br i1 %c, label %guarded, label %deopt +; CHECK: br i1 %c, label %guarded, label %deopt, !prof !0 ; CHECK: deopt: ; CHECK-NEXT: call void (...) @llvm.experimental.deoptimize.isVoid(i32 1, i32 2, double 5.000000e+02) [ "deopt"(i32 2, i32 3) ] ; CHECK-NEXT: ret void @@ -53,7 +53,7 @@ define i32 @f_zero_args(i1* %c_ptr) { call void(i1, ...) @llvm.experimental.guard(i1 %c) [ "deopt"(i32 2, i32 3) ] ret i32 500 -; CHECK: br i1 %c, label %guarded, label %deopt +; CHECK: br i1 %c, label %guarded, label %deopt, !prof !0 ; CHECK: deopt: ; CHECK-NEXT: %deoptcall = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"(i32 2, i32 3) ] ; CHECK-NEXT: ret i32 %deoptcall @@ -63,7 +63,7 @@ define i32 @f_zero_args(i1* %c_ptr) { define i8 @f_with_make_implicit_md(i32* %ptr) { ; CHECK-LABEL: @f_with_make_implicit_md( -; CHECK: br i1 %notNull, label %guarded, label %deopt, !make.implicit !0 +; CHECK: br i1 %notNull, label %guarded, label %deopt, !prof !0, !make.implicit !1 ; CHECK: deopt: ; CHECK-NEXT: %deoptcall = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ "deopt"(i32 1) ] ; CHECK-NEXT: ret i8 %deoptcall @@ -72,3 +72,5 @@ define i8 @f_with_make_implicit_md(i32* %ptr) { call void(i1, ...) @llvm.experimental.guard(i1 %notNull, i32 1) [ "deopt"(i32 1) ], !make.implicit !{} ret i8 5 } + +!0 = !{!"branch_weights", i32 1048576, i32 1}