[llvm] [InstCombine] Fold icmp of gep chains (PR #146714)

Nikita Popov via llvm-commits llvm-commits at lists.llvm.org
Wed Jul 2 07:58:12 PDT 2025


https://github.com/nikic created https://github.com/llvm/llvm-project/pull/146714

This extends https://github.com/llvm/llvm-project/pull/144065 to the general case of an icmp between two GEP chains that have a common base.

>From 11ed1435c4726dc2c945ead667a341a289e51ca1 Mon Sep 17 00:00:00 2001
From: Nikita Popov <npopov at redhat.com>
Date: Wed, 2 Jul 2025 14:58:19 +0200
Subject: [PATCH 1/2] Add tests for icmp of gep chains with common base

---
 llvm/test/Transforms/InstCombine/icmp-gep.ll | 140 +++++++++++++++++++
 1 file changed, 140 insertions(+)

diff --git a/llvm/test/Transforms/InstCombine/icmp-gep.ll b/llvm/test/Transforms/InstCombine/icmp-gep.ll
index 3f104056fb1f2..1528de34489db 100644
--- a/llvm/test/Transforms/InstCombine/icmp-gep.ll
+++ b/llvm/test/Transforms/InstCombine/icmp-gep.ll
@@ -849,3 +849,143 @@ define i1 @gep_mugtiple_ugt_inbounds_nusw(ptr %base, i64 %idx, i64 %idx2) {
   %cmp = icmp ugt ptr %gep2, %base
   ret i1 %cmp
 }
+
+define i1 @gep_gep_multiple_eq(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_eq(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr i32, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr i32, ptr %gep3, i64 %idx4
+  %cmp = icmp eq ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_eq_nuw(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_eq_nuw(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr nuw i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr nuw i32, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr nuw i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr nuw i32, ptr %gep3, i64 %idx4
+  %cmp = icmp eq ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_eq_nuw_different_scales(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_eq_nuw_different_scales(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i64, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr nuw i64, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr nuw i64, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr nuw i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr nuw i64, ptr %gep3, i64 %idx4
+  %cmp = icmp eq ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_eq_partial_nuw_different_scales(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_eq_partial_nuw_different_scales(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i64, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i64, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr nuw i64, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr nuw i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr i64, ptr %gep3, i64 %idx4
+  %cmp = icmp eq ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_eq_partial_inbounds_different_scales(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_eq_partial_inbounds_different_scales(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr inbounds i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr inbounds i64, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr inbounds i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i64, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr inbounds i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr inbounds i64, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr inbounds i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr i64, ptr %gep3, i64 %idx4
+  %cmp = icmp eq ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_ult_nuw(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_ult_nuw(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr nuw i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr nuw i32, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr nuw i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr nuw i32, ptr %gep3, i64 %idx4
+  %cmp = icmp ult ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_ult_missing_nuw(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_ult_missing_nuw(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr nuw i32, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr nuw i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr i32, ptr %gep3, i64 %idx4
+  %cmp = icmp ult ptr %gep2, %gep4
+  ret i1 %cmp
+}
+
+define i1 @gep_gep_multiple_ult_nuw_multi_use(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
+; CHECK-LABEL: @gep_gep_multiple_ult_nuw_multi_use(
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
+; CHECK-NEXT:    [[GEP5:%.*]] = getelementptr nuw i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    call void @use(ptr [[GEP2]])
+; CHECK-NEXT:    call void @use(ptr [[GEP5]])
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult ptr [[GEP2]], [[GEP5]]
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
+  %gep2 = getelementptr nuw i32, ptr %gep1, i64 %idx2
+  %gep3 = getelementptr nuw i32, ptr %base, i64 %idx3
+  %gep4 = getelementptr nuw i32, ptr %gep3, i64 %idx4
+  call void @use(ptr %gep2)
+  call void @use(ptr %gep4)
+  %cmp = icmp ult ptr %gep2, %gep4
+  ret i1 %cmp
+}

>From 91fc73e6de3595b6422043bbf4e4d5c562a310bc Mon Sep 17 00:00:00 2001
From: Nikita Popov <npopov at redhat.com>
Date: Thu, 12 Jun 2025 14:43:42 +0200
Subject: [PATCH 2/2] support folding icmp of gep chains with common base

---
 .../InstCombine/InstCombineCompares.cpp       | 24 +++---
 llvm/test/Transforms/InstCombine/icmp-gep.ll  | 78 ++++++++++---------
 2 files changed, 54 insertions(+), 48 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 6737b50405ee2..1b13a11e4652f 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -752,8 +752,7 @@ Instruction *InstCombinerImpl::foldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
 
     // If the base pointers are different, but the indices are the same, just
     // compare the base pointer.
-    Value *PtrBase = GEPLHS->getOperand(0);
-    if (PtrBase != GEPRHS->getOperand(0)) {
+    if (GEPLHS->getOperand(0) != GEPRHS->getOperand(0)) {
       bool IndicesTheSame =
           GEPLHS->getNumOperands() == GEPRHS->getNumOperands() &&
           GEPLHS->getPointerOperand()->getType() ==
@@ -779,7 +778,7 @@ Instruction *InstCombinerImpl::foldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
       if (GEPLHS->isInBounds() && GEPRHS->isInBounds() &&
           (GEPLHS->hasAllConstantIndices() || GEPLHS->hasOneUse()) &&
           (GEPRHS->hasAllConstantIndices() || GEPRHS->hasOneUse()) &&
-          PtrBase->stripPointerCasts() ==
+          GEPLHS->getOperand(0)->stripPointerCasts() ==
               GEPRHS->getOperand(0)->stripPointerCasts() &&
           !GEPLHS->getType()->isVectorTy()) {
         Value *LOffset = EmitGEPOffset(GEPLHS);
@@ -802,14 +801,10 @@ Instruction *InstCombinerImpl::foldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
                                         LOffset, ROffset);
         return replaceInstUsesWith(I, Cmp);
       }
-
-      // Otherwise, the base pointers are different and the indices are
-      // different. Try convert this to an indexed compare by looking through
-      // PHIs/casts.
-      return transformToIndexedCompare(GEPLHS, RHS, Cond, DL, *this);
     }
 
-    if (GEPLHS->getNumOperands() == GEPRHS->getNumOperands() &&
+    if (GEPLHS->getOperand(0) == GEPRHS->getOperand(0) &&
+        GEPLHS->getNumOperands() == GEPRHS->getNumOperands() &&
         GEPLHS->getSourceElementType() == GEPRHS->getSourceElementType()) {
       // If the GEPs only differ by one index, compare it.
       unsigned NumDifferences = 0; // Keep track of # differences.
@@ -846,11 +841,14 @@ Instruction *InstCombinerImpl::foldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
       }
     }
 
-    if (CanFold(NW)) {
+    if (Base.Ptr && CanFold(Base.LHSNW & Base.RHSNW)) {
       // ((gep Ptr, OFFSET1) cmp (gep Ptr, OFFSET2)  --->  (OFFSET1 cmp OFFSET2)
-      Value *L = EmitGEPOffset(GEPLHS, /*RewriteGEP=*/true);
-      Value *R = EmitGEPOffset(GEPRHS, /*RewriteGEP=*/true);
-      return NewICmp(NW, L, R);
+      Type *IdxTy = DL.getIndexType(GEPLHS->getType());
+      Value *L =
+          EmitGEPOffsets(Base.LHSGEPs, Base.LHSNW, IdxTy, /*RewriteGEP=*/true);
+      Value *R =
+          EmitGEPOffsets(Base.RHSGEPs, Base.RHSNW, IdxTy, /*RewriteGEP=*/true);
+      return NewICmp(Base.LHSNW & Base.RHSNW, L, R);
     }
   }
 
diff --git a/llvm/test/Transforms/InstCombine/icmp-gep.ll b/llvm/test/Transforms/InstCombine/icmp-gep.ll
index 1528de34489db..6fd1eb112b450 100644
--- a/llvm/test/Transforms/InstCombine/icmp-gep.ll
+++ b/llvm/test/Transforms/InstCombine/icmp-gep.ll
@@ -852,11 +852,11 @@ define i1 @gep_mugtiple_ugt_inbounds_nusw(ptr %base, i64 %idx, i64 %idx2) {
 
 define i1 @gep_gep_multiple_eq(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_eq(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
-; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    [[GEP1_IDX1:%.*]] = add i64 [[IDX1:%.*]], [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3_IDX2:%.*]] = add i64 [[IDX3:%.*]], [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP_UNSHIFTED:%.*]] = xor i64 [[GEP1_IDX1]], [[GEP3_IDX2]]
+; CHECK-NEXT:    [[CMP_MASK:%.*]] = and i64 [[CMP_UNSHIFTED]], 4611686018427387903
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[CMP_MASK]], 0
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr i32, ptr %base, i64 %idx1
@@ -869,11 +869,9 @@ define i1 @gep_gep_multiple_eq(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %
 
 define i1 @gep_gep_multiple_eq_nuw(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_eq_nuw(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr nuw i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
-; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    [[GEP1_IDX1:%.*]] = add i64 [[IDX1:%.*]], [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3_IDX2:%.*]] = add i64 [[IDX3:%.*]], [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[GEP1_IDX1]], [[GEP3_IDX2]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
@@ -886,11 +884,13 @@ define i1 @gep_gep_multiple_eq_nuw(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i
 
 define i1 @gep_gep_multiple_eq_nuw_different_scales(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_eq_nuw_different_scales(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i64, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr nuw i64, ptr [[GEP3]], i64 [[IDX4:%.*]]
-; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    [[GEP1_IDX:%.*]] = shl nuw i64 [[IDX1:%.*]], 2
+; CHECK-NEXT:    [[GEP2_IDX:%.*]] = shl nuw i64 [[IDX2:%.*]], 3
+; CHECK-NEXT:    [[GEP3_IDX:%.*]] = shl nuw i64 [[IDX3:%.*]], 2
+; CHECK-NEXT:    [[GEP4_IDX:%.*]] = shl nuw i64 [[IDX4:%.*]], 3
+; CHECK-NEXT:    [[TMP1:%.*]] = add nuw i64 [[GEP1_IDX]], [[GEP2_IDX]]
+; CHECK-NEXT:    [[TMP2:%.*]] = add nuw i64 [[GEP3_IDX]], [[GEP4_IDX]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[TMP1]], [[TMP2]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
@@ -903,11 +903,13 @@ define i1 @gep_gep_multiple_eq_nuw_different_scales(ptr %base, i64 %idx1, i64 %i
 
 define i1 @gep_gep_multiple_eq_partial_nuw_different_scales(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_eq_partial_nuw_different_scales(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i64, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i64, ptr [[GEP3]], i64 [[IDX4:%.*]]
-; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    [[GEP1_IDX:%.*]] = shl nuw i64 [[IDX1:%.*]], 2
+; CHECK-NEXT:    [[GEP2_IDX:%.*]] = shl nuw i64 [[IDX2:%.*]], 3
+; CHECK-NEXT:    [[GEP3_IDX:%.*]] = shl nuw i64 [[IDX3:%.*]], 2
+; CHECK-NEXT:    [[GEP4_IDX:%.*]] = shl i64 [[IDX4:%.*]], 3
+; CHECK-NEXT:    [[TMP1:%.*]] = add nuw i64 [[GEP1_IDX]], [[GEP2_IDX]]
+; CHECK-NEXT:    [[TMP2:%.*]] = add i64 [[GEP3_IDX]], [[GEP4_IDX]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[TMP1]], [[TMP2]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
@@ -920,11 +922,13 @@ define i1 @gep_gep_multiple_eq_partial_nuw_different_scales(ptr %base, i64 %idx1
 
 define i1 @gep_gep_multiple_eq_partial_inbounds_different_scales(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_eq_partial_inbounds_different_scales(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr inbounds i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr inbounds i64, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr inbounds i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr i64, ptr [[GEP3]], i64 [[IDX4:%.*]]
-; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    [[GEP1_IDX:%.*]] = shl nsw i64 [[IDX1:%.*]], 2
+; CHECK-NEXT:    [[GEP2_IDX:%.*]] = shl nsw i64 [[IDX2:%.*]], 3
+; CHECK-NEXT:    [[GEP3_IDX:%.*]] = shl nsw i64 [[IDX3:%.*]], 2
+; CHECK-NEXT:    [[GEP4_IDX:%.*]] = shl i64 [[IDX4:%.*]], 3
+; CHECK-NEXT:    [[TMP1:%.*]] = add nsw i64 [[GEP1_IDX]], [[GEP2_IDX]]
+; CHECK-NEXT:    [[TMP2:%.*]] = add i64 [[GEP3_IDX]], [[GEP4_IDX]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[TMP1]], [[TMP2]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr inbounds i32, ptr %base, i64 %idx1
@@ -937,11 +941,9 @@ define i1 @gep_gep_multiple_eq_partial_inbounds_different_scales(ptr %base, i64
 
 define i1 @gep_gep_multiple_ult_nuw(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_ult_nuw(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP4:%.*]] = getelementptr nuw i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
-; CHECK-NEXT:    [[CMP:%.*]] = icmp ult ptr [[GEP2]], [[GEP4]]
+; CHECK-NEXT:    [[GEP1_IDX1:%.*]] = add i64 [[IDX1:%.*]], [[IDX2:%.*]]
+; CHECK-NEXT:    [[GEP3_IDX2:%.*]] = add i64 [[IDX3:%.*]], [[IDX4:%.*]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[GEP1_IDX1]], [[GEP3_IDX2]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1
@@ -971,13 +973,19 @@ define i1 @gep_gep_multiple_ult_missing_nuw(ptr %base, i64 %idx1, i64 %idx2, i64
 
 define i1 @gep_gep_multiple_ult_nuw_multi_use(ptr %base, i64 %idx1, i64 %idx2, i64 %idx3, i64 %idx4) {
 ; CHECK-LABEL: @gep_gep_multiple_ult_nuw_multi_use(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i32, ptr [[BASE:%.*]], i64 [[IDX1:%.*]]
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i32, ptr [[GEP1]], i64 [[IDX2:%.*]]
-; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i32, ptr [[BASE]], i64 [[IDX3:%.*]]
-; CHECK-NEXT:    [[GEP5:%.*]] = getelementptr nuw i32, ptr [[GEP3]], i64 [[IDX4:%.*]]
+; CHECK-NEXT:    [[GEP1_IDX:%.*]] = shl nuw i64 [[IDX1:%.*]], 2
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr nuw i8, ptr [[BASE:%.*]], i64 [[GEP1_IDX]]
+; CHECK-NEXT:    [[GEP2_IDX:%.*]] = shl nuw i64 [[IDX2:%.*]], 2
+; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr nuw i8, ptr [[GEP1]], i64 [[GEP2_IDX]]
+; CHECK-NEXT:    [[GEP3_IDX:%.*]] = shl nuw i64 [[IDX3:%.*]], 2
+; CHECK-NEXT:    [[GEP3:%.*]] = getelementptr nuw i8, ptr [[BASE]], i64 [[GEP3_IDX]]
+; CHECK-NEXT:    [[GEP4_IDX:%.*]] = shl nuw i64 [[IDX4:%.*]], 2
+; CHECK-NEXT:    [[GEP5:%.*]] = getelementptr nuw i8, ptr [[GEP3]], i64 [[GEP4_IDX]]
 ; CHECK-NEXT:    call void @use(ptr [[GEP2]])
 ; CHECK-NEXT:    call void @use(ptr [[GEP5]])
-; CHECK-NEXT:    [[CMP:%.*]] = icmp ult ptr [[GEP2]], [[GEP5]]
+; CHECK-NEXT:    [[TMP1:%.*]] = add nuw i64 [[GEP1_IDX]], [[GEP2_IDX]]
+; CHECK-NEXT:    [[TMP2:%.*]] = add nuw i64 [[GEP3_IDX]], [[GEP4_IDX]]
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ult i64 [[TMP1]], [[TMP2]]
 ; CHECK-NEXT:    ret i1 [[CMP]]
 ;
   %gep1 = getelementptr nuw i32, ptr %base, i64 %idx1



More information about the llvm-commits mailing list