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-rw-r--r--llvm/lib/Analysis/GuardUtils.cpp5
-rw-r--r--llvm/lib/Transforms/Scalar/GuardWidening.cpp13
-rw-r--r--llvm/lib/Transforms/Scalar/LoopPredication.cpp2
-rw-r--r--llvm/test/Transforms/GuardWidening/basic_widenable_condition_guards.ll18
-rw-r--r--llvm/test/Transforms/GuardWidening/mixed_guards.ll3
-rw-r--r--llvm/test/Transforms/SimplifyCFG/wc-widen-block.ll60
6 files changed, 78 insertions, 23 deletions
diff --git a/llvm/lib/Analysis/GuardUtils.cpp b/llvm/lib/Analysis/GuardUtils.cpp
index cad92f6e56b..863443cea35 100644
--- a/llvm/lib/Analysis/GuardUtils.cpp
+++ b/llvm/lib/Analysis/GuardUtils.cpp
@@ -42,6 +42,11 @@ bool llvm::parseWidenableBranch(const User *U, Value *&Condition,
if (!match(U, m_Br(m_And(m_Value(Condition), m_Value(WidenableCondition)),
IfTrueBB, IfFalseBB)))
return false;
+ // For the branch to be (easily) widenable, it must not correlate with other
+ // branches. Thus, the widenable condition must have a single use.
+ if (!WidenableCondition->hasOneUse() ||
+ !cast<BranchInst>(U)->getCondition()->hasOneUse())
+ return false;
// TODO: At the moment, we only recognize the branch if the WC call in this
// specific position. We should generalize!
return match(WidenableCondition,
diff --git a/llvm/lib/Transforms/Scalar/GuardWidening.cpp b/llvm/lib/Transforms/Scalar/GuardWidening.cpp
index 2697d780956..269e641b8f1 100644
--- a/llvm/lib/Transforms/Scalar/GuardWidening.cpp
+++ b/llvm/lib/Transforms/Scalar/GuardWidening.cpp
@@ -271,16 +271,17 @@ class GuardWideningImpl {
void widenGuard(Instruction *ToWiden, Value *NewCondition,
bool InvertCondition) {
Value *Result;
+
widenCondCommon(getCondition(ToWiden), NewCondition, ToWiden, Result,
InvertCondition);
- Value *WidenableCondition = nullptr;
if (isGuardAsWidenableBranch(ToWiden)) {
- auto *Cond = cast<BranchInst>(ToWiden)->getCondition();
- WidenableCondition = cast<BinaryOperator>(Cond)->getOperand(1);
+ auto *BI = cast<BranchInst>(ToWiden);
+ auto *And = cast<Instruction>(BI->getCondition());
+ And->setOperand(0, Result);
+ And->moveBefore(ToWiden);
+ assert(isGuardAsWidenableBranch(ToWiden) && "still widenable?");
+ return;
}
- if (WidenableCondition)
- Result = BinaryOperator::CreateAnd(Result, WidenableCondition,
- "guard.chk", ToWiden);
setCondition(ToWiden, Result);
}
diff --git a/llvm/lib/Transforms/Scalar/LoopPredication.cpp b/llvm/lib/Transforms/Scalar/LoopPredication.cpp
index 885c0e8f4b8..495f0bc83d6 100644
--- a/llvm/lib/Transforms/Scalar/LoopPredication.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopPredication.cpp
@@ -823,9 +823,9 @@ bool LoopPredication::widenWidenableBranchGuardConditions(
Value *AllChecks = Builder.CreateAnd(Checks);
auto *OldCond = BI->getCondition();
BI->setCondition(AllChecks);
+ RecursivelyDeleteTriviallyDeadInstructions(OldCond);
assert(isGuardAsWidenableBranch(BI) &&
"Stopped being a guard after transform?");
- RecursivelyDeleteTriviallyDeadInstructions(OldCond);
LLVM_DEBUG(dbgs() << "Widened checks = " << NumWidened << "\n");
return true;
diff --git a/llvm/test/Transforms/GuardWidening/basic_widenable_condition_guards.ll b/llvm/test/Transforms/GuardWidening/basic_widenable_condition_guards.ll
index 605178a7868..a71e7c30f00 100644
--- a/llvm/test/Transforms/GuardWidening/basic_widenable_condition_guards.ll
+++ b/llvm/test/Transforms/GuardWidening/basic_widenable_condition_guards.ll
@@ -8,8 +8,7 @@ define void @f_0(i1 %cond_0, i1 %cond_1) {
; CHECK-LABEL: @f_0(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0:%.*]], [[WIDENABLE_COND]]
-; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_1:%.*]]
+; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0:%.*]], [[COND_1:%.*]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
@@ -52,8 +51,7 @@ define void @f_1(i1 %cond_0, i1 %cond_1) {
; CHECK-LABEL: @f_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0:%.*]], [[WIDENABLE_COND]]
-; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_1:%.*]]
+; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0:%.*]], [[COND_1:%.*]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
@@ -113,7 +111,6 @@ define void @f_2(i32 %a, i32 %b) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[COND_0:%.*]] = icmp ult i32 [[A:%.*]], 10
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0]], [[WIDENABLE_COND]]
; CHECK-NEXT: [[COND_1:%.*]] = icmp ult i32 [[B:%.*]], 10
; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_1]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
@@ -235,7 +232,6 @@ define void @f_4(i32 %a, i32 %b) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[COND_0:%.*]] = icmp ult i32 [[A:%.*]], 10
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0]], [[WIDENABLE_COND]]
; CHECK-NEXT: [[COND_1:%.*]] = icmp ult i32 [[B:%.*]], 10
; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_1]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
@@ -294,7 +290,6 @@ define void @f_5(i32 %a) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[COND_0:%.*]] = icmp ugt i32 [[A:%.*]], 7
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0]], [[WIDENABLE_COND]]
; CHECK-NEXT: [[WIDE_CHK:%.*]] = icmp uge i32 [[A]], 11
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
@@ -403,7 +398,6 @@ define void @f_7(i32 %a, i1* %cond_buf) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[COND_1:%.*]] = load volatile i1, i1* [[COND_BUF:%.*]]
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_1]], [[WIDENABLE_COND]]
; CHECK-NEXT: [[COND_3:%.*]] = icmp ult i32 [[A:%.*]], 7
; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_1]], [[COND_3]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
@@ -491,9 +485,8 @@ define void @f_8(i32 %a, i1 %cond_1, i1 %cond_2) {
; CHECK-NEXT: br i1 undef, label [[LOOP]], label [[LEAVE:%.*]]
; CHECK: leave:
; CHECK-NEXT: [[WIDENABLE_COND3:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND4:%.*]] = and i1 [[COND_2:%.*]], [[WIDENABLE_COND3]]
; CHECK-NEXT: [[COND_3:%.*]] = icmp ult i32 [[A:%.*]], 7
-; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_2]], [[COND_3]]
+; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_2:%.*]], [[COND_3]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND3]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED1:%.*]], label [[DEOPT2:%.*]], !prof !0
; CHECK: deopt2:
@@ -671,8 +664,7 @@ define void @f_11(i32 %a, i1 %cond_0, i1 %cond_1) {
; CHECK-NEXT: br label [[OUTER_HEADER:%.*]]
; CHECK: outer_header:
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0:%.*]], [[WIDENABLE_COND]]
-; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_1:%.*]]
+; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0:%.*]], [[COND_1:%.*]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
@@ -734,7 +726,6 @@ define void @f_12(i32 %a0) {
; CHECK-LABEL: @f_12(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 true, [[WIDENABLE_COND]]
; CHECK-NEXT: [[A1:%.*]] = mul i32 [[A0:%.*]], [[A0]]
; CHECK-NEXT: [[A2:%.*]] = mul i32 [[A1]], [[A1]]
; CHECK-NEXT: [[A3:%.*]] = mul i32 [[A2]], [[A2]]
@@ -840,7 +831,6 @@ define void @f_13(i32 %a) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[COND_0:%.*]] = icmp ult i32 [[A:%.*]], 14
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0]], [[WIDENABLE_COND]]
; CHECK-NEXT: [[WIDE_CHK:%.*]] = icmp ult i32 [[A]], 10
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
diff --git a/llvm/test/Transforms/GuardWidening/mixed_guards.ll b/llvm/test/Transforms/GuardWidening/mixed_guards.ll
index 58908c0ff80..f136f98da18 100644
--- a/llvm/test/Transforms/GuardWidening/mixed_guards.ll
+++ b/llvm/test/Transforms/GuardWidening/mixed_guards.ll
@@ -45,8 +45,7 @@ define void @test_02(i1 %cond_0, i1 %cond_1) {
; CHECK-LABEL: @test_02(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
-; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0:%.*]], [[WIDENABLE_COND]]
-; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_1:%.*]]
+; CHECK-NEXT: [[WIDE_CHK:%.*]] = and i1 [[COND_0:%.*]], [[COND_1:%.*]]
; CHECK-NEXT: [[GUARD_CHK:%.*]] = and i1 [[WIDE_CHK]], [[WIDENABLE_COND]]
; CHECK-NEXT: br i1 [[GUARD_CHK]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
; CHECK: deopt:
diff --git a/llvm/test/Transforms/SimplifyCFG/wc-widen-block.ll b/llvm/test/Transforms/SimplifyCFG/wc-widen-block.ll
index d6be9cd53a1..79bbefd1266 100644
--- a/llvm/test/Transforms/SimplifyCFG/wc-widen-block.ll
+++ b/llvm/test/Transforms/SimplifyCFG/wc-widen-block.ll
@@ -305,6 +305,66 @@ deopt2:
ret i32 %deoptret2
}
+; This one is subtle - We can't widen only one branch use of the
+; widenable condition as two branches are correlated. We'd have to
+; widen them *both*.
+define i32 @neg_correlated(i1 %cond_0, i1 %cond_1, i32* %p) {
+; CHECK-LABEL: @neg_correlated(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[WIDENABLE_COND:%.*]] = call i1 @llvm.experimental.widenable.condition()
+; CHECK-NEXT: [[EXIPLICIT_GUARD_COND:%.*]] = and i1 [[COND_0:%.*]], [[WIDENABLE_COND]]
+; CHECK-NEXT: br i1 [[EXIPLICIT_GUARD_COND]], label [[GUARDED:%.*]], label [[DEOPT:%.*]], !prof !0
+; CHECK: deopt:
+; CHECK-NEXT: [[DEOPTRET:%.*]] = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"() ]
+; CHECK-NEXT: ret i32 [[DEOPTRET]]
+; CHECK: guarded:
+; CHECK-NEXT: [[EXIPLICIT_GUARD_COND2:%.*]] = and i1 [[COND_1:%.*]], [[WIDENABLE_COND]]
+; CHECK-NEXT: br i1 [[EXIPLICIT_GUARD_COND2]], label [[GUARDED2:%.*]], label [[DEOPT2:%.*]], !prof !0
+; CHECK: deopt2:
+; CHECK-NEXT: [[DEOPTRET2:%.*]] = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"() ]
+; CHECK-NEXT: ret i32 [[DEOPTRET2]]
+; CHECK: guarded2:
+; CHECK-NEXT: [[V:%.*]] = load i32, i32* [[P:%.*]]
+; CHECK-NEXT: [[COND_2:%.*]] = icmp eq i32 [[V]], 0
+; CHECK-NEXT: br i1 [[COND_2]], label [[RETURN:%.*]], label [[DEOPT3:%.*]], !prof !0
+; CHECK: deopt3:
+; CHECK-NEXT: [[DEOPTRET3:%.*]] = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"() ]
+; CHECK-NEXT: ret i32 [[DEOPTRET3]]
+; CHECK: return:
+; CHECK-NEXT: ret i32 0
+;
+entry:
+ %widenable_cond = call i1 @llvm.experimental.widenable.condition()
+ %exiplicit_guard_cond = and i1 %cond_0, %widenable_cond
+ br i1 %exiplicit_guard_cond, label %guarded, label %deopt, !prof !0
+
+deopt:
+ %deoptret = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"() ]
+ ret i32 %deoptret
+
+guarded:
+ %exiplicit_guard_cond2 = and i1 %cond_1, %widenable_cond
+ br i1 %exiplicit_guard_cond2, label %guarded2, label %deopt2, !prof !0
+
+deopt2:
+ %deoptret2 = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"() ]
+ ret i32 %deoptret2
+
+guarded2:
+ %v = load i32, i32* %p
+ %cond_2 = icmp eq i32 %v, 0
+ br i1 %cond_2, label %return, label %deopt3, !prof !0
+
+deopt3:
+ %deoptret3 = call i32 (...) @llvm.experimental.deoptimize.i32() [ "deopt"() ]
+ ret i32 %deoptret3
+
+return:
+ ret i32 0
+}
+
+
+
declare void @unknown()
declare i32 @unknown_i32()
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