From 7f5fbe3e3eb93ce5dbf33617d6b89fed0342942c Mon Sep 17 00:00:00 2001
From: Artur Pilipenko <apilipenko@azulsystems.com>
Date: Wed, 25 Jan 2017 14:20:52 +0000
Subject: [PATCH] [InstCombine] Canonicalize guards for AND condition

This is a partial fix for Bug 31520 - [guards] canonicalize guards in instcombine

Reviewed By: apilipenko

Differential Revision: https://reviews.llvm.org/D29074

Patch by Maxim Kazantsev.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293058 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../InstCombine/InstCombineCalls.cpp          | 17 ++++++++++++++++
 test/Transforms/InstCombine/call-guard.ll     | 20 +++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 679596766fc..523b35c31bb 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -2878,6 +2878,23 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
     if (match(II->getNextNode(),
               m_Intrinsic<Intrinsic::experimental_guard>(m_Specific(IIOperand))))
       return eraseInstFromFunction(*II);
+
+    // Canonicalize guard(a && b) -> guard(a); guard(b);
+    // Note: New guard intrinsics created here are registered by
+    // the InstCombineIRInserter object.
+    Function *GuardIntrinsic = II->getCalledFunction();
+    Value *A, *B;
+    OperandBundleDef DeoptOB(*II->getOperandBundle(LLVMContext::OB_deopt));
+    if (match(IIOperand, m_And(m_Value(A), m_Value(B)))) {
+      CallInst *GuardA =
+          Builder->CreateCall(GuardIntrinsic, A, {DeoptOB}, II->getName());
+      CallInst *GuardB =
+          Builder->CreateCall(GuardIntrinsic, B, {DeoptOB}, II->getName());
+      auto CC = II->getCallingConv();
+      GuardA->setCallingConv(CC);
+      GuardB->setCallingConv(CC);
+      return eraseInstFromFunction(*II);
+    }
     break;
   }
   }
diff --git a/test/Transforms/InstCombine/call-guard.ll b/test/Transforms/InstCombine/call-guard.ll
index 18da465e606..d392ede574f 100644
--- a/test/Transforms/InstCombine/call-guard.ll
+++ b/test/Transforms/InstCombine/call-guard.ll
@@ -28,3 +28,23 @@ define void @test_guard_adjacent_neg(i1 %A, i1 %B) {
   call void(i1, ...) @llvm.experimental.guard( i1 %B )[ "deopt"() ]
   ret void
 }
+
+define void @test_guard_and(i1 %A, i1 %B) {
+; CHECK-LABEL: @test_guard_and(
+; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 %A) [ "deopt"() ]
+; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 %B) [ "deopt"() ]
+; CHECK-NEXT:    ret void
+  %C = and i1 %A, %B
+  call void(i1, ...) @llvm.experimental.guard( i1 %C )[ "deopt"() ]
+  ret void
+}
+
+define void @test_guard_and_non_default_cc(i1 %A, i1 %B) {
+; CHECK-LABEL: @test_guard_and_non_default_cc(
+; CHECK-NEXT:    call cc99 void (i1, ...) @llvm.experimental.guard(i1 %A) [ "deopt"() ]
+; CHECK-NEXT:    call cc99 void (i1, ...) @llvm.experimental.guard(i1 %B) [ "deopt"() ]
+; CHECK-NEXT:    ret void
+  %C = and i1 %A, %B
+  call cc99 void(i1, ...) @llvm.experimental.guard( i1 %C )[ "deopt"() ]
+  ret void
+}
-- 
2.40.0