From 091be7b530a80e269183d98b41f393016e33af82 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Tue, 14 Apr 2015 15:56:33 +0000
Subject: [PATCH] Revert "The code that originally made me discover this is:"

This reverts commit r234898.
CodeGen/ARM/2013-10-11-select-stalls.ll was faling.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234903 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Analysis/BranchProbabilityInfo.cpp       |  8 ------
 test/Analysis/BranchProbabilityInfo/basic.ll | 28 --------------------
 test/CodeGen/AArch64/arm64-call-tailcalls.ll |  2 +-
 test/CodeGen/Mips/octeon.ll                  |  4 +--
 4 files changed, 3 insertions(+), 39 deletions(-)

diff --git a/lib/Analysis/BranchProbabilityInfo.cpp b/lib/Analysis/BranchProbabilityInfo.cpp
index d7cee3afaf5..14800f4a28b 100644
--- a/lib/Analysis/BranchProbabilityInfo.cpp
+++ b/lib/Analysis/BranchProbabilityInfo.cpp
@@ -379,14 +379,6 @@ bool BranchProbabilityInfo::calcZeroHeuristics(BasicBlock *BB) {
   if (!CV)
     return false;
 
-  // If the LHS is the result of AND'ing a value with a single bit bitmask,
-  // we don't have information about probabilities.
-  if (Instruction *LHS = dyn_cast<Instruction>(CI->getOperand(0)))
-    if (LHS->getOpcode() == Instruction::And)
-      if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(LHS->getOperand(1)))
-        if (AndRHS->getUniqueInteger().isPowerOf2())
-          return false;
-
   bool isProb;
   if (CV->isZero()) {
     switch (CI->getPredicate()) {
diff --git a/test/Analysis/BranchProbabilityInfo/basic.ll b/test/Analysis/BranchProbabilityInfo/basic.ll
index 2c9c1561868..0f669119bfe 100644
--- a/test/Analysis/BranchProbabilityInfo/basic.ll
+++ b/test/Analysis/BranchProbabilityInfo/basic.ll
@@ -212,31 +212,3 @@ exit:
   ret i32 %result
 }
 
-define i32 @zero3(i32 %i, i32 %a, i32 %b) {
-; CHECK: Printing analysis {{.*}} for function 'zero3'
-entry:
-; AND'ing with a single bit bitmask essentially leads to a bool comparison,
-; meaning we don't have probability information.
-  %and = and i32 %i, 2
-  %tobool = icmp eq i32 %and, 0
-  br i1 %tobool, label %then, label %else
-; CHECK: edge entry -> then probability is 16 / 32
-; CHECK: edge entry -> else probability is 16 / 32
-
-then:
-; AND'ing with other bitmask might be something else, so we still assume the
-; usual probabilities.
-  %and2 = and i32 %i, 5
-  %tobool2 = icmp eq i32 %and2, 0
-  br i1 %tobool2, label %else, label %exit
-; CHECK: edge then -> else probability is 12 / 32
-; CHECK: edge then -> exit probability is 20 / 32
-
-else:
-  br label %exit
-
-exit:
-  %result = phi i32 [ %a, %then ], [ %b, %else ]
-  ret i32 %result
-}
-
diff --git a/test/CodeGen/AArch64/arm64-call-tailcalls.ll b/test/CodeGen/AArch64/arm64-call-tailcalls.ll
index 6621db25da5..71d932787ce 100644
--- a/test/CodeGen/AArch64/arm64-call-tailcalls.ll
+++ b/test/CodeGen/AArch64/arm64-call-tailcalls.ll
@@ -53,9 +53,9 @@ bb:                                               ; preds = %entry
 
 define i32 @t8(i32 %x) nounwind ssp {
 ; CHECK-LABEL: t8:
-; CHECK: b	_c
 ; CHECK: b	_a
 ; CHECK: b	_b
+; CHECK: b	_c
   %and = and i32 %x, 1
   %tobool = icmp eq i32 %and, 0
   br i1 %tobool, label %if.end, label %if.then
diff --git a/test/CodeGen/Mips/octeon.ll b/test/CodeGen/Mips/octeon.ll
index 499ce3c1ddb..97e12e721f5 100644
--- a/test/CodeGen/Mips/octeon.ll
+++ b/test/CodeGen/Mips/octeon.ll
@@ -93,7 +93,7 @@ entry:
 ; ALL-LABEL: bbit0:
 ; OCTEON: bbit0   $4, 3, $[[BB0:BB[0-9_]+]]
 ; MIPS64: andi  $[[T0:[0-9]+]], $4, 8
-; MIPS64: bnez  $[[T0]], $[[BB0:BB[0-9_]+]]
+; MIPS64: beqz  $[[T0]], $[[BB0:BB[0-9_]+]]
   %bit = and i64 %a, 8
   %res = icmp eq i64 %bit, 0
   br i1 %res, label %endif, label %if
@@ -111,7 +111,7 @@ entry:
 ; MIPS64: daddiu  $[[T0:[0-9]+]], $zero, 1
 ; MIPS64: dsll    $[[T1:[0-9]+]], $[[T0]], 35
 ; MIPS64: and     $[[T2:[0-9]+]], $4, $[[T1]]
-; MIPS64: bnez    $[[T2]], $[[BB0:BB[0-9_]+]]
+; MIPS64: beqz    $[[T2]], $[[BB0:BB[0-9_]+]]
   %bit = and i64 %a, 34359738368
   %res = icmp eq i64 %bit, 0
   br i1 %res, label %endif, label %if
-- 
2.34.1