[llvm] r303295 - [InstSimplify] handle all icmp i1 X, C in one place; NFCI
Sanjay Patel via llvm-commits
llvm-commits at lists.llvm.org
Wed May 17 13:27:56 PDT 2017
Author: spatel
Date: Wed May 17 15:27:55 2017
New Revision: 303295
URL: http://llvm.org/viewvc/llvm-project?rev=303295&view=rev
Log:
[InstSimplify] handle all icmp i1 X, C in one place; NFCI
We already handled all of the new tests identically, but several
of those went through a lot of unnecessary processing before
getting folded.
Another motivation for grouping these cases together is that
InstCombine needs a similar fold. Currently, it handles the
'not' cases inefficiently which can lead to bugs as described
in the post-commit comments of:
https://reviews.llvm.org/D32143
Added:
llvm/trunk/test/Transforms/InstSimplify/icmp-bool-constant.ll
Modified:
llvm/trunk/lib/Analysis/InstructionSimplify.cpp
Modified: llvm/trunk/lib/Analysis/InstructionSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/InstructionSimplify.cpp?rev=303295&r1=303294&r2=303295&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/InstructionSimplify.cpp (original)
+++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp Wed May 17 15:27:55 2017
@@ -2260,28 +2260,49 @@ static Value *simplifyICmpOfBools(CmpIns
if (!OpTy->getScalarType()->isIntegerTy(1))
return nullptr;
- switch (Pred) {
- default:
- break;
- case ICmpInst::ICMP_EQ:
- // X == 1 -> X
- if (match(RHS, m_One()))
+ // A boolean compared to true/false can be simplified in 14 out of the 20
+ // (10 predicates * 2 constants) possible combinations. Cases not handled here
+ // require a 'not' of the LHS, so those must be transformed in InstCombine.
+ if (match(RHS, m_Zero())) {
+ switch (Pred) {
+ case CmpInst::ICMP_NE: // X != 0 -> X
+ case CmpInst::ICMP_UGT: // X >u 0 -> X
+ case CmpInst::ICMP_SLT: // X <s 0 -> X
return LHS;
- break;
- case ICmpInst::ICMP_NE:
- // X != 0 -> X
- if (match(RHS, m_Zero()))
- return LHS;
- break;
- case ICmpInst::ICMP_UGT:
- // X >u 0 -> X
- if (match(RHS, m_Zero()))
+
+ case CmpInst::ICMP_ULT: // X <u 0 -> false
+ case CmpInst::ICMP_SGT: // X >s 0 -> false
+ return getFalse(ITy);
+
+ case CmpInst::ICMP_UGE: // X >=u 0 -> true
+ case CmpInst::ICMP_SLE: // X <=s 0 -> true
+ return getTrue(ITy);
+
+ default: break;
+ }
+ } else if (match(RHS, m_One())) {
+ switch (Pred) {
+ case CmpInst::ICMP_EQ: // X == 1 -> X
+ case CmpInst::ICMP_UGE: // X >=u 1 -> X
+ case CmpInst::ICMP_SLE: // X <=s -1 -> X
return LHS;
+
+ case CmpInst::ICMP_UGT: // X >u 1 -> false
+ case CmpInst::ICMP_SLT: // X <s -1 -> false
+ return getFalse(ITy);
+
+ case CmpInst::ICMP_ULE: // X <=u 1 -> true
+ case CmpInst::ICMP_SGE: // X >=s -1 -> true
+ return getTrue(ITy);
+
+ default: break;
+ }
+ }
+
+ switch (Pred) {
+ default:
break;
case ICmpInst::ICMP_UGE:
- // X >=u 1 -> X
- if (match(RHS, m_One()))
- return LHS;
if (isImpliedCondition(RHS, LHS, Q.DL).getValueOr(false))
return getTrue(ITy);
break;
@@ -2296,16 +2317,6 @@ static Value *simplifyICmpOfBools(CmpIns
if (isImpliedCondition(LHS, RHS, Q.DL).getValueOr(false))
return getTrue(ITy);
break;
- case ICmpInst::ICMP_SLT:
- // X <s 0 -> X
- if (match(RHS, m_Zero()))
- return LHS;
- break;
- case ICmpInst::ICMP_SLE:
- // X <=s -1 -> X
- if (match(RHS, m_One()))
- return LHS;
- break;
case ICmpInst::ICMP_ULE:
if (isImpliedCondition(LHS, RHS, Q.DL).getValueOr(false))
return getTrue(ITy);
Added: llvm/trunk/test/Transforms/InstSimplify/icmp-bool-constant.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstSimplify/icmp-bool-constant.ll?rev=303295&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/InstSimplify/icmp-bool-constant.ll (added)
+++ llvm/trunk/test/Transforms/InstSimplify/icmp-bool-constant.ll Wed May 17 15:27:55 2017
@@ -0,0 +1,171 @@
+; RUN: opt < %s -instsimplify -S | FileCheck %s
+
+; Test all integer predicates with bool types and true/false constants.
+; Use vectors to provide test coverage that is not duplicated in other folds.
+
+define <2 x i1> @eq_t(<2 x i1> %a) {
+; CHECK-LABEL: @eq_t(
+; CHECK-NEXT: ret <2 x i1> %a
+;
+ %r = icmp eq <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @eq_f(<2 x i1> %a) {
+; CHECK-LABEL: @eq_f(
+; CHECK-NEXT: [[R:%.*]] = icmp eq <2 x i1> %a, zeroinitializer
+; CHECK-NEXT: ret <2 x i1> [[R]]
+;
+ %r = icmp eq <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ne_t(<2 x i1> %a) {
+; CHECK-LABEL: @ne_t(
+; CHECK-NEXT: [[R:%.*]] = icmp ne <2 x i1> %a, <i1 true, i1 true>
+; CHECK-NEXT: ret <2 x i1> [[R]]
+;
+ %r = icmp ne <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ne_f(<2 x i1> %a) {
+; CHECK-LABEL: @ne_f(
+; CHECK-NEXT: ret <2 x i1> %a
+;
+ %r = icmp ne <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ugt_t(<2 x i1> %a) {
+; CHECK-LABEL: @ugt_t(
+; CHECK-NEXT: ret <2 x i1> zeroinitializer
+;
+ %r = icmp ugt <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ugt_f(<2 x i1> %a) {
+; CHECK-LABEL: @ugt_f(
+; CHECK-NEXT: ret <2 x i1> %a
+;
+ %r = icmp ugt <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ult_t(<2 x i1> %a) {
+; CHECK-LABEL: @ult_t(
+; CHECK-NEXT: [[R:%.*]] = icmp ult <2 x i1> %a, <i1 true, i1 true>
+; CHECK-NEXT: ret <2 x i1> [[R]]
+;
+ %r = icmp ult <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ult_f(<2 x i1> %a) {
+; CHECK-LABEL: @ult_f(
+; CHECK-NEXT: ret <2 x i1> zeroinitializer
+;
+ %r = icmp ult <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @sgt_t(<2 x i1> %a) {
+; CHECK-LABEL: @sgt_t(
+; CHECK-NEXT: [[R:%.*]] = icmp sgt <2 x i1> %a, <i1 true, i1 true>
+; CHECK-NEXT: ret <2 x i1> [[R]]
+;
+ %r = icmp sgt <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @sgt_f(<2 x i1> %a) {
+; CHECK-LABEL: @sgt_f(
+; CHECK-NEXT: ret <2 x i1> zeroinitializer
+;
+ %r = icmp sgt <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @slt_t(<2 x i1> %a) {
+; CHECK-LABEL: @slt_t(
+; CHECK-NEXT: ret <2 x i1> zeroinitializer
+;
+ %r = icmp slt <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @slt_f(<2 x i1> %a) {
+; CHECK-LABEL: @slt_f(
+; CHECK-NEXT: ret <2 x i1> %a
+;
+ %r = icmp slt <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @uge_t(<2 x i1> %a) {
+; CHECK-LABEL: @uge_t(
+; CHECK-NEXT: ret <2 x i1> %a
+;
+ %r = icmp uge <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @uge_f(<2 x i1> %a) {
+; CHECK-LABEL: @uge_f(
+; CHECK-NEXT: ret <2 x i1> <i1 true, i1 true>
+;
+ %r = icmp uge <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ule_t(<2 x i1> %a) {
+; CHECK-LABEL: @ule_t(
+; CHECK-NEXT: ret <2 x i1> <i1 true, i1 true>
+;
+ %r = icmp ule <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @ule_f(<2 x i1> %a) {
+; CHECK-LABEL: @ule_f(
+; CHECK-NEXT: [[R:%.*]] = icmp ule <2 x i1> %a, zeroinitializer
+; CHECK-NEXT: ret <2 x i1> [[R]]
+;
+ %r = icmp ule <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @sge_t(<2 x i1> %a) {
+; CHECK-LABEL: @sge_t(
+; CHECK-NEXT: ret <2 x i1> <i1 true, i1 true>
+;
+ %r = icmp sge <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @sge_f(<2 x i1> %a) {
+; CHECK-LABEL: @sge_f(
+; CHECK-NEXT: [[R:%.*]] = icmp sge <2 x i1> %a, zeroinitializer
+; CHECK-NEXT: ret <2 x i1> [[R]]
+;
+ %r = icmp sge <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @sle_t(<2 x i1> %a) {
+; CHECK-LABEL: @sle_t(
+; CHECK-NEXT: ret <2 x i1> %a
+;
+ %r = icmp sle <2 x i1> %a, <i1 true, i1 true>
+ ret <2 x i1> %r
+}
+
+define <2 x i1> @sle_f(<2 x i1> %a) {
+; CHECK-LABEL: @sle_f(
+; CHECK-NEXT: ret <2 x i1> <i1 true, i1 true>
+;
+ %r = icmp sle <2 x i1> %a, <i1 false, i1 false>
+ ret <2 x i1> %r
+}
+
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