[clang] [llvm] [Instcombine] use zext's nneg flag for icmp folding (PR #70845)

LĂ©onard Oest O'Leary via cfe-commits cfe-commits at lists.llvm.org
Wed Nov 1 12:05:59 PDT 2023


https://github.com/leo-ard updated https://github.com/llvm/llvm-project/pull/70845

>From 6bb97fd48d59b7f79fdf90a2b27e9220f417fac7 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Mon, 30 Oct 2023 18:01:27 -0400
Subject: [PATCH 1/8] Add NonNeg check for InstCombine

---
 llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 7574987d0e23141..4751d870da7a777 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -5587,11 +5587,15 @@ Instruction *InstCombinerImpl::foldICmpWithZextOrSext(ICmpInst &ICmp) {
         return new ICmpInst(ICmp.getPredicate(), Builder.CreateOr(X, Y),
                             Constant::getNullValue(X->getType()));
 
+      // Treat "zext nneg" as "sext"
+      bool IsNonNeg0 = isa<PossiblyNonNegInst>(ICmp.getOperand(0));
+      bool IsNonNeg1 = isa<PossiblyNonNegInst>(ICmp.getOperand(1));
+
       // If we have mismatched casts, treat the zext of a non-negative source as
       // a sext to simulate matching casts. Otherwise, we are done.
       // TODO: Can we handle some predicates (equality) without non-negative?
-      if ((IsZext0 && isKnownNonNegative(X, DL, 0, &AC, &ICmp, &DT)) ||
-          (IsZext1 && isKnownNonNegative(Y, DL, 0, &AC, &ICmp, &DT)))
+      if ((IsZext0 && (IsNonNeg0 || isKnownNonNegative(X, DL, 0, &AC, &ICmp, &DT))) ||
+          (IsZext1 && (IsNonNeg1 || isKnownNonNegative(Y, DL, 0, &AC, &ICmp, &DT))))
         IsSignedExt = true;
       else
         return nullptr;

>From 6570c0a864805408928a0d7a54dd0098f2d58419 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Mon, 30 Oct 2023 18:03:44 -0400
Subject: [PATCH 2/8] Add tests for min/max

---
 clang/test/CodeGen/X86/min_max.c              |  19 ++
 .../Transforms/SCCP/icmp-fold-with-cast.ll    | 185 ++++++++++++++++++
 2 files changed, 204 insertions(+)
 create mode 100644 clang/test/CodeGen/X86/min_max.c
 create mode 100644 llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll

diff --git a/clang/test/CodeGen/X86/min_max.c b/clang/test/CodeGen/X86/min_max.c
new file mode 100644
index 000000000000000..7af8181cc9ff367
--- /dev/null
+++ b/clang/test/CodeGen/X86/min_max.c
@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 %s -O2 -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s
+
+short vecreduce_smax_v2i16(int n, short* v)
+{
+  // CHECK: @llvm.smax
+  short p = 0;
+  for (int i = 0; i < n; ++i)
+    p = p < v[i] ? v[i] : p;
+  return p;
+}
+
+short vecreduce_smin_v2i16(int n, short* v)
+{
+  // CHECK: @llvm.smin
+  short p = 0;
+  for (int i = 0; i < n; ++i)
+    p = p > v[i] ? v[i] : p;
+  return p;
+}
\ No newline at end of file
diff --git a/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll b/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll
new file mode 100644
index 000000000000000..90b2c123081fb49
--- /dev/null
+++ b/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll
@@ -0,0 +1,185 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --tool ./bin/opt --version 3
+; See PRXXX for more details
+; RUN: opt < %s -S -passes=ipsccp | FileCheck %s
+
+
+define signext i32 @sext_sext(i16 %x, i16 %y) {
+; CHECK-LABEL: define signext i32 @sext_sext(
+; CHECK-SAME: i16 [[X:%.*]], i16 [[Y:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CONV:%.*]] = sext i16 [[X]] to i32
+; CHECK-NEXT:    [[CONV1:%.*]] = sext i16 [[Y]] to i32
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i16 [[X]], [[Y]]
+; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
+; CHECK:       cond.true:
+; CHECK-NEXT:    br label [[COND_END:%.*]]
+; CHECK:       cond.false:
+; CHECK-NEXT:    br label [[COND_END]]
+; CHECK:       cond.end:
+; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ 0, [[COND_TRUE]] ], [ 1, [[COND_FALSE]] ]
+; CHECK-NEXT:    ret i32 [[COND]]
+;
+entry:
+  %conv = sext i16 %x to i32
+  %conv1 = sext i16 %y to i32
+  %cmp2 = icmp sgt i32 %conv, %conv1
+  br i1 %cmp2, label %cond.true, label %cond.false
+
+cond.true:                                        ; preds = %for.body
+  br label %cond.end
+
+cond.false:                                       ; preds = %for.body
+  br label %cond.end
+
+cond.end:                                         ; preds = %cond.false, %cond.true
+  %cond = phi i32 [ 0, %cond.true ], [ 1, %cond.false ]
+  ret i32 %cond
+}
+
+
+define signext i32 @zext_zext(i16 %x, i16 %y) {
+; CHECK-LABEL: define signext i32 @zext_zext(
+; CHECK-SAME: i16 [[X:%.*]], i16 [[Y:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CONV:%.*]] = zext i16 [[X]] to i32
+; CHECK-NEXT:    [[CONV1:%.*]] = zext i16 [[Y]] to i32
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i16 [[X]], [[Y]]
+; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
+; CHECK:       cond.true:
+; CHECK-NEXT:    br label [[COND_END:%.*]]
+; CHECK:       cond.false:
+; CHECK-NEXT:    br label [[COND_END]]
+; CHECK:       cond.end:
+; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ 0, [[COND_TRUE]] ], [ 1, [[COND_FALSE]] ]
+; CHECK-NEXT:    ret i32 [[COND]]
+;
+entry:
+  %conv = zext i16 %x to i32
+  %conv1 = zext i16 %y to i32
+  %cmp2 = icmp sgt i32 %conv, %conv1
+  br i1 %cmp2, label %cond.true, label %cond.false
+
+cond.true:                                        ; preds = %for.body
+  br label %cond.end
+
+cond.false:                                       ; preds = %for.body
+  br label %cond.end
+
+cond.end:                                         ; preds = %cond.false, %cond.true
+  %cond = phi i32 [ 0, %cond.true ], [ 1, %cond.false ]
+  ret i32 %cond
+}
+
+
+define signext i16 @zext_positive_and_sext(i32 noundef %n, ptr noundef %v) {
+; CHECK-LABEL: define signext i16 @zext_positive_and_sext(
+; CHECK-SAME: i32 noundef [[N:%.*]], ptr noundef [[V:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_COND:%.*]]
+; CHECK:       for.cond:
+; CHECK-NEXT:    [[P_0:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[CONV8:%.*]], [[COND_END:%.*]] ]
+; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[INC:%.*]], [[COND_END]] ]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[I_0]], [[N]]
+; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY:%.*]], label [[FOR_COND_CLEANUP:%.*]]
+; CHECK:       for.body:
+; CHECK-NEXT:    [[CONV:%.*]] = zext i16 [[P_0]] to i32
+; CHECK-NEXT:    [[IDXPROM:%.*]] = sext i32 [[I_0]] to i64
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr i16, ptr [[V]], i64 [[IDXPROM]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i16, ptr [[ARRAYIDX]], align 2
+; CHECK-NEXT:    [[CONV1:%.*]] = sext i16 [[TMP0]] to i32
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i16 [[P_0]], [[TMP0]]
+; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
+; CHECK:       cond.true:
+; CHECK-NEXT:    br label [[COND_END]]
+; CHECK:       cond.false:
+; CHECK-NEXT:    br label [[COND_END]]
+; CHECK:       for.cond.cleanup:
+; CHECK-NEXT:    ret i16 [[P_0]]
+; CHECK:       cond.end:
+; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ [[CONV1]], [[COND_TRUE]] ], [ [[CONV]], [[COND_FALSE]] ]
+; CHECK-NEXT:    [[CONV8]] = trunc i32 [[COND]] to i16
+; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], 1
+; CHECK-NEXT:    br label [[FOR_COND]]
+;
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %cond.end, %entry
+  %p.0 = phi i16 [ 0, %entry ], [ %conv8, %cond.end ]
+  %i.0 = phi i32 [ 0, %entry ], [ %inc, %cond.end ]
+  %cmp = icmp slt i32 %i.0, %n
+  br i1 %cmp, label %for.body, label %for.cond.cleanup
+
+for.body:                                         ; preds = %for.cond
+  %conv = zext i16 %p.0 to i32                    ;; %p.0 is always positive here
+  %idxprom = sext i32 %i.0 to i64
+  %arrayidx = getelementptr i16, ptr %v, i64 %idxprom
+  %0 = load i16, ptr %arrayidx, align 2
+  %conv1 = sext i16 %0 to i32
+  %cmp2 = icmp slt i32 %conv, %conv1
+  br i1 %cmp2, label %cond.true, label %cond.false
+
+cond.true:                                        ; preds = %for.body
+  br label %cond.end
+
+cond.false:                                       ; preds = %for.body
+  br label %cond.end
+
+for.cond.cleanup:                                 ; preds = %for.cond
+  ret i16 %p.0
+
+cond.end:                                         ; preds = %cond.false, %cond.true
+  %cond = phi i32 [ %conv1, %cond.true ], [ %conv, %cond.false ]
+  %conv8 = trunc i32 %cond to i16
+  %inc = add nsw i32 %i.0, 1
+  br label %for.cond
+}
+
+
+
+define signext i16 @sext_and_zext_positive(i16 %x) {
+; CHECK-LABEL: define signext i16 @sext_and_zext_positive(
+; CHECK-SAME: i16 [[X:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_COND:%.*]]
+; CHECK:       for.cond:
+; CHECK-NEXT:    [[V:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[COND_END:%.*]] ]
+; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
+; CHECK:       for.body:
+; CHECK-NEXT:    [[CONV:%.*]] = zext i16 [[V]] to i32
+; CHECK-NEXT:    [[CONV1:%.*]] = sext i16 [[X]] to i32
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i16 [[X]], [[V]]
+; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
+; CHECK:       cond.true:
+; CHECK-NEXT:    br label [[COND_END]]
+; CHECK:       cond.false:
+; CHECK-NEXT:    br label [[COND_END]]
+; CHECK:       cond.end:
+; CHECK-NEXT:    [[A:%.*]] = phi i16 [ 10, [[COND_TRUE]] ], [ 20, [[COND_FALSE]] ]
+; CHECK-NEXT:    [[INC]] = add nuw nsw i16 [[A]], 1
+; CHECK-NEXT:    br label [[FOR_COND]]
+;
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %cond.end, %entry
+  %v = phi i16 [ 0, %entry ], [ %inc, %cond.end ] ;; always positive
+  br label %for.body
+
+for.body:                                         ; preds = %for.cond
+  %conv = zext i16 %v to i32                    ;; %p.0 is always positive here
+  %conv1 = sext i16 %x to i32                    ;; %p.0 is always positive here
+  %cmp2 = icmp slt i32 %conv1, %conv ;; positive/positive
+  br i1 %cmp2, label %cond.true, label %cond.false
+
+cond.true:                                        ; preds = %for.body
+  br label %cond.end
+
+cond.false:                                       ; preds = %for.body
+  br label %cond.end
+
+cond.end:                                         ; preds = %cond.false, %cond.true
+  %a = phi i16 [ 10, %cond.true ],  [ 20, %cond.false ]
+  %inc = add i16 %a, 1
+  br label %for.cond
+}

>From d166c4f01d83260c50c07e084cd516956ddac785 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Tue, 31 Oct 2023 13:24:49 -0400
Subject: [PATCH 3/8] Regenerate tests

---
 ...004-11-27-SetCCForCastLargerAndConstant.ll |  5 +-
 .../Transforms/InstCombine/icmp-ext-ext.ll    | 49 ++++++-------------
 .../Transforms/SCCP/icmp-fold-with-cast.ll    |  2 +-
 3 files changed, 19 insertions(+), 37 deletions(-)

diff --git a/llvm/test/Transforms/InstCombine/2004-11-27-SetCCForCastLargerAndConstant.ll b/llvm/test/Transforms/InstCombine/2004-11-27-SetCCForCastLargerAndConstant.ll
index 2e70a95dfde6233..b24a71b8dc15ea6 100644
--- a/llvm/test/Transforms/InstCombine/2004-11-27-SetCCForCastLargerAndConstant.ll
+++ b/llvm/test/Transforms/InstCombine/2004-11-27-SetCCForCastLargerAndConstant.ll
@@ -403,9 +403,8 @@ define i1 @different_size_sext_sext_ule(i7 %x, i4 %y) {
 
 define i1 @different_size_sext_zext_ne(i7 %x, i4 %y) {
 ; CHECK-LABEL: @different_size_sext_zext_ne(
-; CHECK-NEXT:    [[SX:%.*]] = sext i7 [[X:%.*]] to i25
-; CHECK-NEXT:    [[ZY:%.*]] = zext i4 [[Y:%.*]] to i25
-; CHECK-NEXT:    [[R:%.*]] = icmp ne i25 [[SX]], [[ZY]]
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i4 [[Y:%.*]] to i7
+; CHECK-NEXT:    [[R:%.*]] = icmp ne i7 [[TMP1]], [[X:%.*]]
 ; CHECK-NEXT:    ret i1 [[R]]
 ;
   %sx = sext i7 %x to i25
diff --git a/llvm/test/Transforms/InstCombine/icmp-ext-ext.ll b/llvm/test/Transforms/InstCombine/icmp-ext-ext.ll
index f70e48e27384619..87532c1faff1526 100644
--- a/llvm/test/Transforms/InstCombine/icmp-ext-ext.ll
+++ b/llvm/test/Transforms/InstCombine/icmp-ext-ext.ll
@@ -119,9 +119,7 @@ define <2 x i1> @sext_sext_uge_op0_wide(<2 x i16> %x, <2 x i8> %y) {
 
 define i1 @zext_sext_sgt(i8 %x, i8 %y) {
 ; CHECK-LABEL: @zext_sext_sgt(
-; CHECK-NEXT:    [[A:%.*]] = zext i8 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = sext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp sgt i32 [[A]], [[B]]
+; CHECK-NEXT:    [[C:%.*]] = icmp sgt i8 [[X:%.*]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = zext i8 %x to i32
@@ -132,9 +130,7 @@ define i1 @zext_sext_sgt(i8 %x, i8 %y) {
 
 define i1 @zext_sext_ugt(i8 %x, i8 %y) {
 ; CHECK-LABEL: @zext_sext_ugt(
-; CHECK-NEXT:    [[A:%.*]] = zext i8 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = sext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp ugt i32 [[A]], [[B]]
+; CHECK-NEXT:    [[C:%.*]] = icmp ugt i8 [[X:%.*]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = zext i8 %x to i32
@@ -145,9 +141,7 @@ define i1 @zext_sext_ugt(i8 %x, i8 %y) {
 
 define i1 @zext_sext_eq(i8 %x, i8 %y) {
 ; CHECK-LABEL: @zext_sext_eq(
-; CHECK-NEXT:    [[A:%.*]] = zext i8 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = sext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp eq i32 [[A]], [[B]]
+; CHECK-NEXT:    [[C:%.*]] = icmp eq i8 [[X:%.*]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = zext i8 %x to i32
@@ -158,9 +152,8 @@ define i1 @zext_sext_eq(i8 %x, i8 %y) {
 
 define i1 @zext_sext_sle_op0_narrow(i8 %x, i16 %y) {
 ; CHECK-LABEL: @zext_sext_sle_op0_narrow(
-; CHECK-NEXT:    [[A:%.*]] = zext i8 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = sext i16 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp sle i32 [[A]], [[B]]
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i8 [[X:%.*]] to i16
+; CHECK-NEXT:    [[C:%.*]] = icmp sle i16 [[TMP1]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = zext i8 %x to i32
@@ -171,9 +164,8 @@ define i1 @zext_sext_sle_op0_narrow(i8 %x, i16 %y) {
 
 define i1 @zext_sext_ule_op0_wide(i9 %x, i8 %y) {
 ; CHECK-LABEL: @zext_sext_ule_op0_wide(
-; CHECK-NEXT:    [[A:%.*]] = zext i9 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = sext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp ule i32 [[A]], [[B]]
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i8 [[Y:%.*]] to i9
+; CHECK-NEXT:    [[C:%.*]] = icmp uge i9 [[TMP1]], [[X:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = zext i9 %x to i32
@@ -184,9 +176,7 @@ define i1 @zext_sext_ule_op0_wide(i9 %x, i8 %y) {
 
 define i1 @sext_zext_slt(i8 %x, i8 %y) {
 ; CHECK-LABEL: @sext_zext_slt(
-; CHECK-NEXT:    [[A:%.*]] = sext i8 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = zext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp slt i32 [[A]], [[B]]
+; CHECK-NEXT:    [[C:%.*]] = icmp slt i8 [[X:%.*]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = sext i8 %x to i32
@@ -197,9 +187,7 @@ define i1 @sext_zext_slt(i8 %x, i8 %y) {
 
 define i1 @sext_zext_ult(i8 %x, i8 %y) {
 ; CHECK-LABEL: @sext_zext_ult(
-; CHECK-NEXT:    [[A:%.*]] = sext i8 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = zext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp ult i32 [[A]], [[B]]
+; CHECK-NEXT:    [[C:%.*]] = icmp ult i8 [[X:%.*]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = sext i8 %x to i32
@@ -210,9 +198,7 @@ define i1 @sext_zext_ult(i8 %x, i8 %y) {
 
 define <2 x i1> @sext_zext_ne(<2 x i8> %x, <2 x i8> %y) {
 ; CHECK-LABEL: @sext_zext_ne(
-; CHECK-NEXT:    [[A:%.*]] = sext <2 x i8> [[X:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[B:%.*]] = zext <2 x i8> [[Y:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[C:%.*]] = icmp ne <2 x i32> [[A]], [[B]]
+; CHECK-NEXT:    [[C:%.*]] = icmp ne <2 x i8> [[X:%.*]], [[Y:%.*]]
 ; CHECK-NEXT:    ret <2 x i1> [[C]]
 ;
   %a = sext <2 x i8> %x to <2 x i32>
@@ -223,9 +209,8 @@ define <2 x i1> @sext_zext_ne(<2 x i8> %x, <2 x i8> %y) {
 
 define i1 @sext_zext_sge_op0_narrow(i5 %x, i8 %y) {
 ; CHECK-LABEL: @sext_zext_sge_op0_narrow(
-; CHECK-NEXT:    [[A:%.*]] = sext i5 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = zext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp sge i32 [[A]], [[B]]
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i5 [[X:%.*]] to i8
+; CHECK-NEXT:    [[C:%.*]] = icmp sge i8 [[TMP1]], [[Y:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = sext i5 %x to i32
@@ -236,9 +221,8 @@ define i1 @sext_zext_sge_op0_narrow(i5 %x, i8 %y) {
 
 define i1 @sext_zext_uge_op0_wide(i16 %x, i8 %y) {
 ; CHECK-LABEL: @sext_zext_uge_op0_wide(
-; CHECK-NEXT:    [[A:%.*]] = sext i16 [[X:%.*]] to i32
-; CHECK-NEXT:    [[B:%.*]] = zext i8 [[Y:%.*]] to i32
-; CHECK-NEXT:    [[C:%.*]] = icmp uge i32 [[A]], [[B]]
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i8 [[Y:%.*]] to i16
+; CHECK-NEXT:    [[C:%.*]] = icmp ule i16 [[TMP1]], [[X:%.*]]
 ; CHECK-NEXT:    ret i1 [[C]]
 ;
   %a = sext i16 %x to i32
@@ -396,9 +380,8 @@ define i1 @zext_eq_sext(i1 %a, i1 %b) {
 
 define i1 @zext_eq_sext_fail_not_i1(i1 %a, i8 %b) {
 ; CHECK-LABEL: @zext_eq_sext_fail_not_i1(
-; CHECK-NEXT:    [[CONV:%.*]] = zext i1 [[A:%.*]] to i32
-; CHECK-NEXT:    [[CONV3_NEG:%.*]] = sext i8 [[B:%.*]] to i32
-; CHECK-NEXT:    [[TOBOOL4:%.*]] = icmp eq i32 [[CONV]], [[CONV3_NEG]]
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i1 [[A:%.*]] to i8
+; CHECK-NEXT:    [[TOBOOL4:%.*]] = icmp eq i8 [[TMP1]], [[B:%.*]]
 ; CHECK-NEXT:    ret i1 [[TOBOOL4]]
 ;
   %conv = zext i1 %a to i32
diff --git a/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll b/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll
index 90b2c123081fb49..4e9597f7e70daaa 100644
--- a/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll
+++ b/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --tool ./bin/opt --version 3
 ; See PRXXX for more details
-; RUN: opt < %s -S -passes=ipsccp | FileCheck %s
+; RUN-./bin/opt: opt < %s -S -passes=ipsccp | FileCheck %s
 
 
 define signext i32 @sext_sext(i16 %x, i16 %y) {

>From f3d39f2005c1c124f07aaee7efd9192e1c7cfcc5 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Tue, 31 Oct 2023 13:54:29 -0400
Subject: [PATCH 4/8] Move test to InstCombine

---
 llvm/test/Transforms/{SCCP => InstCombine}/icmp-fold-with-cast.ll | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename llvm/test/Transforms/{SCCP => InstCombine}/icmp-fold-with-cast.ll (100%)

diff --git a/llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll b/llvm/test/Transforms/InstCombine/icmp-fold-with-cast.ll
similarity index 100%
rename from llvm/test/Transforms/SCCP/icmp-fold-with-cast.ll
rename to llvm/test/Transforms/InstCombine/icmp-fold-with-cast.ll

>From 02d1f8878983bf91689618bea4098d062e4bf9e0 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Tue, 31 Oct 2023 13:58:55 -0400
Subject: [PATCH 5/8] Reformat according to git clang format

---
 llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 4751d870da7a777..30591ab0bea93a3 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -5594,8 +5594,10 @@ Instruction *InstCombinerImpl::foldICmpWithZextOrSext(ICmpInst &ICmp) {
       // If we have mismatched casts, treat the zext of a non-negative source as
       // a sext to simulate matching casts. Otherwise, we are done.
       // TODO: Can we handle some predicates (equality) without non-negative?
-      if ((IsZext0 && (IsNonNeg0 || isKnownNonNegative(X, DL, 0, &AC, &ICmp, &DT))) ||
-          (IsZext1 && (IsNonNeg1 || isKnownNonNegative(Y, DL, 0, &AC, &ICmp, &DT))))
+      if ((IsZext0 &&
+           (IsNonNeg0 || isKnownNonNegative(X, DL, 0, &AC, &ICmp, &DT))) ||
+          (IsZext1 &&
+           (IsNonNeg1 || isKnownNonNegative(Y, DL, 0, &AC, &ICmp, &DT))))
         IsSignedExt = true;
       else
         return nullptr;

>From 2fc611be63c7c6b33d34d27ed7e649a409ba701e Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Wed, 1 Nov 2023 13:16:20 -0400
Subject: [PATCH 6/8] check with hasNonNeg (comment 2)

---
 llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 30591ab0bea93a3..96eec52b64ad35c 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -5588,8 +5588,11 @@ Instruction *InstCombinerImpl::foldICmpWithZextOrSext(ICmpInst &ICmp) {
                             Constant::getNullValue(X->getType()));
 
       // Treat "zext nneg" as "sext"
-      bool IsNonNeg0 = isa<PossiblyNonNegInst>(ICmp.getOperand(0));
-      bool IsNonNeg1 = isa<PossiblyNonNegInst>(ICmp.getOperand(1));
+      auto *NonNegInst0 = dyn_cast<PossiblyNonNegInst>(ICmp.getOperand(0));
+      auto *NonNegInst1 = dyn_cast<PossiblyNonNegInst>(ICmp.getOperand(1));
+
+      bool IsNonNeg0 = NonNegInst0 && NonNegInst0->hasNonNeg();
+      bool IsNonNeg1 = NonNegInst1 && NonNegInst1->hasNonNeg();
 
       // If we have mismatched casts, treat the zext of a non-negative source as
       // a sext to simulate matching casts. Otherwise, we are done.

>From d5fa339dcc881413a5b9d0a08fa5df78e2082a72 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Wed, 1 Nov 2023 13:17:33 -0400
Subject: [PATCH 7/8] change test to instcombine (comment 3)

---
 .../InstCombine/icmp-fold-with-cast.ll        | 32 +++++++------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/llvm/test/Transforms/InstCombine/icmp-fold-with-cast.ll b/llvm/test/Transforms/InstCombine/icmp-fold-with-cast.ll
index 4e9597f7e70daaa..119eb6faca7ca41 100644
--- a/llvm/test/Transforms/InstCombine/icmp-fold-with-cast.ll
+++ b/llvm/test/Transforms/InstCombine/icmp-fold-with-cast.ll
@@ -1,14 +1,12 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --tool ./bin/opt --version 3
-; See PRXXX for more details
-; RUN-./bin/opt: opt < %s -S -passes=ipsccp | FileCheck %s
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; See PR-70845 for more details
+; RUN: opt < %s -S -passes=instcombine | FileCheck %s
 
 
 define signext i32 @sext_sext(i16 %x, i16 %y) {
 ; CHECK-LABEL: define signext i32 @sext_sext(
 ; CHECK-SAME: i16 [[X:%.*]], i16 [[Y:%.*]]) {
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[CONV:%.*]] = sext i16 [[X]] to i32
-; CHECK-NEXT:    [[CONV1:%.*]] = sext i16 [[Y]] to i32
 ; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i16 [[X]], [[Y]]
 ; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
 ; CHECK:       cond.true:
@@ -41,9 +39,7 @@ define signext i32 @zext_zext(i16 %x, i16 %y) {
 ; CHECK-LABEL: define signext i32 @zext_zext(
 ; CHECK-SAME: i16 [[X:%.*]], i16 [[Y:%.*]]) {
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    [[CONV:%.*]] = zext i16 [[X]] to i32
-; CHECK-NEXT:    [[CONV1:%.*]] = zext i16 [[Y]] to i32
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i16 [[X]], [[Y]]
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp ugt i16 [[X]], [[Y]]
 ; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
 ; CHECK:       cond.true:
 ; CHECK-NEXT:    br label [[COND_END:%.*]]
@@ -77,16 +73,14 @@ define signext i16 @zext_positive_and_sext(i32 noundef %n, ptr noundef %v) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    br label [[FOR_COND:%.*]]
 ; CHECK:       for.cond:
-; CHECK-NEXT:    [[P_0:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[CONV8:%.*]], [[COND_END:%.*]] ]
+; CHECK-NEXT:    [[P_0:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[COND_OFF0:%.*]], [[COND_END:%.*]] ]
 ; CHECK-NEXT:    [[I_0:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[INC:%.*]], [[COND_END]] ]
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp slt i32 [[I_0]], [[N]]
 ; CHECK-NEXT:    br i1 [[CMP]], label [[FOR_BODY:%.*]], label [[FOR_COND_CLEANUP:%.*]]
 ; CHECK:       for.body:
-; CHECK-NEXT:    [[CONV:%.*]] = zext i16 [[P_0]] to i32
-; CHECK-NEXT:    [[IDXPROM:%.*]] = sext i32 [[I_0]] to i64
+; CHECK-NEXT:    [[IDXPROM:%.*]] = zext nneg i32 [[I_0]] to i64
 ; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr i16, ptr [[V]], i64 [[IDXPROM]]
 ; CHECK-NEXT:    [[TMP0:%.*]] = load i16, ptr [[ARRAYIDX]], align 2
-; CHECK-NEXT:    [[CONV1:%.*]] = sext i16 [[TMP0]] to i32
 ; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i16 [[P_0]], [[TMP0]]
 ; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
 ; CHECK:       cond.true:
@@ -96,9 +90,8 @@ define signext i16 @zext_positive_and_sext(i32 noundef %n, ptr noundef %v) {
 ; CHECK:       for.cond.cleanup:
 ; CHECK-NEXT:    ret i16 [[P_0]]
 ; CHECK:       cond.end:
-; CHECK-NEXT:    [[COND:%.*]] = phi i32 [ [[CONV1]], [[COND_TRUE]] ], [ [[CONV]], [[COND_FALSE]] ]
-; CHECK-NEXT:    [[CONV8]] = trunc i32 [[COND]] to i16
-; CHECK-NEXT:    [[INC]] = add nsw i32 [[I_0]], 1
+; CHECK-NEXT:    [[COND_OFF0]] = phi i16 [ [[TMP0]], [[COND_TRUE]] ], [ [[P_0]], [[COND_FALSE]] ]
+; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[I_0]], 1
 ; CHECK-NEXT:    br label [[FOR_COND]]
 ;
 entry:
@@ -143,20 +136,17 @@ define signext i16 @sext_and_zext_positive(i16 %x) {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    br label [[FOR_COND:%.*]]
 ; CHECK:       for.cond:
-; CHECK-NEXT:    [[V:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[COND_END:%.*]] ]
+; CHECK-NEXT:    [[V:%.*]] = phi i16 [ 0, [[ENTRY:%.*]] ], [ [[A:%.*]], [[COND_END:%.*]] ]
 ; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
 ; CHECK:       for.body:
-; CHECK-NEXT:    [[CONV:%.*]] = zext i16 [[V]] to i32
-; CHECK-NEXT:    [[CONV1:%.*]] = sext i16 [[X]] to i32
-; CHECK-NEXT:    [[CMP2:%.*]] = icmp slt i16 [[X]], [[V]]
+; CHECK-NEXT:    [[CMP2:%.*]] = icmp sgt i16 [[V]], [[X]]
 ; CHECK-NEXT:    br i1 [[CMP2]], label [[COND_TRUE:%.*]], label [[COND_FALSE:%.*]]
 ; CHECK:       cond.true:
 ; CHECK-NEXT:    br label [[COND_END]]
 ; CHECK:       cond.false:
 ; CHECK-NEXT:    br label [[COND_END]]
 ; CHECK:       cond.end:
-; CHECK-NEXT:    [[A:%.*]] = phi i16 [ 10, [[COND_TRUE]] ], [ 20, [[COND_FALSE]] ]
-; CHECK-NEXT:    [[INC]] = add nuw nsw i16 [[A]], 1
+; CHECK-NEXT:    [[A]] = phi i16 [ 11, [[COND_TRUE]] ], [ 21, [[COND_FALSE]] ]
 ; CHECK-NEXT:    br label [[FOR_COND]]
 ;
 entry:

>From 24bf4314042e678fa751ea388f53ccc7a8d5bb02 Mon Sep 17 00:00:00 2001
From: leo-ard <lool4516 at gmail.com>
Date: Wed, 1 Nov 2023 15:04:55 -0400
Subject: [PATCH 8/8] Moving end-to-end test to PhaseOrdering (comment 3)

---
 clang/test/CodeGen/X86/min_max.c              |  19 ---
 .../Transforms/PhaseOrdering/min_max_loop.ll  | 126 ++++++++++++++++++
 2 files changed, 126 insertions(+), 19 deletions(-)
 delete mode 100644 clang/test/CodeGen/X86/min_max.c
 create mode 100644 llvm/test/Transforms/PhaseOrdering/min_max_loop.ll

diff --git a/clang/test/CodeGen/X86/min_max.c b/clang/test/CodeGen/X86/min_max.c
deleted file mode 100644
index 7af8181cc9ff367..000000000000000
--- a/clang/test/CodeGen/X86/min_max.c
+++ /dev/null
@@ -1,19 +0,0 @@
-// RUN: %clang_cc1 %s -O2 -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s
-
-short vecreduce_smax_v2i16(int n, short* v)
-{
-  // CHECK: @llvm.smax
-  short p = 0;
-  for (int i = 0; i < n; ++i)
-    p = p < v[i] ? v[i] : p;
-  return p;
-}
-
-short vecreduce_smin_v2i16(int n, short* v)
-{
-  // CHECK: @llvm.smin
-  short p = 0;
-  for (int i = 0; i < n; ++i)
-    p = p > v[i] ? v[i] : p;
-  return p;
-}
\ No newline at end of file
diff --git a/llvm/test/Transforms/PhaseOrdering/min_max_loop.ll b/llvm/test/Transforms/PhaseOrdering/min_max_loop.ll
new file mode 100644
index 000000000000000..7ea389dfafce68b
--- /dev/null
+++ b/llvm/test/Transforms/PhaseOrdering/min_max_loop.ll
@@ -0,0 +1,126 @@
+; RUN: opt < %s --O3 -S | FileCheck %s
+
+define signext i16 @vecreduce_smax_v2i16(i32 noundef %0, ptr noundef %1) #0 {
+   ;; CHECK: @llvm.smax
+   %3 = alloca i32, align 4
+   %4 = alloca ptr, align 8
+   %5 = alloca i16, align 2
+   %6 = alloca i32, align 4
+   store i32 %0, ptr %3, align 4
+   store ptr %1, ptr %4, align 8
+   store i16 0, ptr %5, align 2
+   store i32 0, ptr %6, align 4
+   br label %7
+ 
+ 7:                                                ; preds = %34, %2
+   %8 = load i32, ptr %6, align 4
+   %9 = load i32, ptr %3, align 4
+   %10 = icmp slt i32 %8, %9
+   br i1 %10, label %11, label %37
+ 
+ 11:                                               ; preds = %7
+   %12 = load i16, ptr %5, align 2
+   %13 = sext i16 %12 to i32
+   %14 = load ptr, ptr %4, align 8
+   %15 = load i32, ptr %6, align 4
+   %16 = sext i32 %15 to i64
+   %17 = getelementptr inbounds i16, ptr %14, i64 %16
+   %18 = load i16, ptr %17, align 2
+   %19 = sext i16 %18 to i32
+   %20 = icmp slt i32 %13, %19
+   br i1 %20, label %21, label %28
+ 
+ 21:                                               ; preds = %11
+   %22 = load ptr, ptr %4, align 8
+   %23 = load i32, ptr %6, align 4
+   %24 = sext i32 %23 to i64
+   %25 = getelementptr inbounds i16, ptr %22, i64 %24
+   %26 = load i16, ptr %25, align 2
+   %27 = sext i16 %26 to i32
+   br label %31
+ 
+ 28:                                               ; preds = %11
+   %29 = load i16, ptr %5, align 2
+   %30 = sext i16 %29 to i32
+   br label %31
+ 
+ 31:                                               ; preds = %28, %21
+   %32 = phi i32 [ %27, %21 ], [ %30, %28 ]
+   %33 = trunc i32 %32 to i16
+   store i16 %33, ptr %5, align 2
+   br label %34
+ 
+ 34:                                               ; preds = %31
+   %35 = load i32, ptr %6, align 4
+   %36 = add nsw i32 %35, 1
+   store i32 %36, ptr %6, align 4
+   br label %7
+ 
+ 37:                                               ; preds = %7
+   %38 = load i16, ptr %5, align 2
+   ret i16 %38
+ }
+
+define signext i16 @vecreduce_smin_v2i16(i32 noundef %0, ptr noundef %1) #0 {
+; CHECK: @llvm.smin
+  %3 = alloca i32, align 4
+  %4 = alloca ptr, align 8
+  %5 = alloca i16, align 2
+  %6 = alloca i32, align 4
+  store i32 %0, ptr %3, align 4
+  store ptr %1, ptr %4, align 8
+  store i16 0, ptr %5, align 2
+  store i32 0, ptr %6, align 4
+  br label %7
+
+7:                                                ; preds = %34, %2
+  %8 = load i32, ptr %6, align 4
+  %9 = load i32, ptr %3, align 4
+  %10 = icmp slt i32 %8, %9
+  br i1 %10, label %11, label %37
+
+11:                                               ; preds = %7
+  %12 = load i16, ptr %5, align 2
+  %13 = sext i16 %12 to i32
+  %14 = load ptr, ptr %4, align 8
+  %15 = load i32, ptr %6, align 4
+  %16 = sext i32 %15 to i64
+  %17 = getelementptr inbounds i16, ptr %14, i64 %16
+  %18 = load i16, ptr %17, align 2
+  %19 = sext i16 %18 to i32
+  %20 = icmp sgt i32 %13, %19
+  br i1 %20, label %21, label %28
+
+21:                                               ; preds = %11
+  %22 = load ptr, ptr %4, align 8
+  %23 = load i32, ptr %6, align 4
+  %24 = sext i32 %23 to i64
+  %25 = getelementptr inbounds i16, ptr %22, i64 %24
+  %26 = load i16, ptr %25, align 2
+  %27 = sext i16 %26 to i32
+  br label %31
+
+28:                                               ; preds = %11
+  %29 = load i16, ptr %5, align 2
+  %30 = sext i16 %29 to i32
+  br label %31
+
+31:                                               ; preds = %28, %21
+  %32 = phi i32 [ %27, %21 ], [ %30, %28 ]
+  %33 = trunc i32 %32 to i16
+  store i16 %33, ptr %5, align 2
+  br label %34
+
+34:                                               ; preds = %31
+  %35 = load i32, ptr %6, align 4
+  %36 = add nsw i32 %35, 1
+  store i32 %36, ptr %6, align 4
+  br label %7 
+
+37:                                               ; preds = %7
+  %38 = load i16, ptr %5, align 2
+  ret i16 %38
+}
+
+
+



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