[llvm] [ValueTracking] isNonEqual Pointers with with a recursive GEP (PR #70459)
via llvm-commits
llvm-commits at lists.llvm.org
Mon Nov 6 04:58:17 PST 2023
https://github.com/bipmis updated https://github.com/llvm/llvm-project/pull/70459
>From 39652a34b4f7a351575f3e6eb11fef2abb929c2e Mon Sep 17 00:00:00 2001
From: bipmis <biplob.mishra at arm.com>
Date: Fri, 27 Oct 2023 15:28:44 +0100
Subject: [PATCH 1/3] Precommit tests for isNonEqualPointers with Recursive GEP
---
.../Analysis/ValueTracking/known-non-equal.ll | 38 ++
.../Analysis/ValueTracking/phi-known-bits.ll | 380 ++++++++++++++++++
2 files changed, 418 insertions(+)
diff --git a/llvm/test/Analysis/ValueTracking/known-non-equal.ll b/llvm/test/Analysis/ValueTracking/known-non-equal.ll
index 79b9b3fd8511b60..bbed4eb92c005fa 100644
--- a/llvm/test/Analysis/ValueTracking/known-non-equal.ll
+++ b/llvm/test/Analysis/ValueTracking/known-non-equal.ll
@@ -1813,5 +1813,43 @@ exit:
ret i1 %res
}
+; Illustrate if 2 pointers are non-equal when one of them is a recursive GEP.
+define i1 @icmp_recursiveGEP_withPtr(ptr noundef %val1) {
+; CHECK-LABEL: @icmp_recursiveGEP_withPtr(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[BOOL:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[BOOL]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %bool = icmp eq ptr %test.0.i, %val1
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i1 [ %bool, %while.end.i ], [ true, %entry ]
+ ret i1 %retval.0.i
+}
!0 = !{ i8 1, i8 5 }
diff --git a/llvm/test/Analysis/ValueTracking/phi-known-bits.ll b/llvm/test/Analysis/ValueTracking/phi-known-bits.ll
index 5227661c837347e..1efb36e41e8088f 100644
--- a/llvm/test/Analysis/ValueTracking/phi-known-bits.ll
+++ b/llvm/test/Analysis/ValueTracking/phi-known-bits.ll
@@ -424,3 +424,383 @@ T:
F:
br label %T
}
+
+;Illustrate if 2 pointers are non-equal when one of them is a recursive GEP.
+;Cases which folds to a canonical icmp(ptr1, ptr2)
+define i1 @recursiveGEP_withPtr_phisub1(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub1(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub1_PhiOperandsCommuted(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub1_PhiOperandsCommuted(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[VAL1]], [[ENTRY:%.*]] ], [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %val1, %entry ], [ %test.0.i, %while.cond.i ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub1_SubOperandsCommuted(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub1_SubOperandsCommuted(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.rhs.cast.i, %sub.ptr.lhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub2(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub2(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 -1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 -1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub3(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub3(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I_IDX:%.*]] = phi i64 [ [[A_PN_I_ADD:%.*]], [[WHILE_COND_I]] ], [ 7, [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[A_PN_I_ADD]] = add nuw nsw i64 [[A_PN_I_IDX]], 1
+; CHECK-NEXT: [[TEST_0_I_PTR:%.*]] = getelementptr inbounds i8, ptr [[VAL1]], i64 [[A_PN_I_ADD]]
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I_PTR]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i64 [[A_PN_I_ADD]], 5
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %test.val1 = getelementptr inbounds i8, ptr %val1, i64 7
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %test.val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %1 = getelementptr inbounds i8, ptr %val1, i64 5
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub1_notKnownNonEqual1(ptr noundef %val1, i64 %val2) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub1_notKnownNonEqual1(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = getelementptr inbounds i8, ptr [[VAL1]], i64 [[VAL2:%.*]]
+; CHECK-NEXT: [[TMP2:%.*]] = icmp eq ptr [[TEST_0_I]], [[TMP1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP2]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %1 = getelementptr inbounds i8, ptr %val1, i64 %val2
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub1_notKnownNonEqual2(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub1_notKnownNonEqual2(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[TEST_VAL1:%.*]] = getelementptr inbounds i8, ptr [[VAL1:%.*]], i64 -1
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[TEST_VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %test.val1 = getelementptr inbounds i8, ptr %val1, i64 -1
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %test.val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub1_notKnownNonEqual3(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub1_notKnownNonEqual3(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[TEST_VAL1:%.*]] = getelementptr inbounds i8, ptr [[VAL1:%.*]], i64 5
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[TEST_VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 -1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %test.val1 = getelementptr inbounds i8, ptr %val1, i64 5
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %test.val1, %entry ]
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 -1
+ %0 = load i8, ptr %test.0.i, align 2
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %test.0.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
+
+define i1 @recursiveGEP_withPtr_phisub_maybeZero(ptr noundef %val1) {
+; CHECK-LABEL: @recursiveGEP_withPtr_phisub_maybeZero(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
+; CHECK: while.cond.i:
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[A_PN_I]], align 2
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
+; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
+; CHECK: while.end.i:
+; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[A_PN_I]], [[VAL1]]
+; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
+; CHECK: _Z9stringlenPKs.exit:
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+;
+entry:
+ %cmp.i = icmp eq ptr %val1, null
+ br i1 %cmp.i, label %_Z9stringlenPKs.exit, label %while.cond.i
+
+while.cond.i:
+ %a.pn.i = phi ptr [ %test.0.i, %while.cond.i ], [ %val1, %entry ]
+ %0 = load i8, ptr %a.pn.i, align 2
+ %test.0.i = getelementptr inbounds i8, ptr %a.pn.i, i64 1
+ %cmp3.not.i = icmp eq i8 %0, 0
+ br i1 %cmp3.not.i, label %while.end.i, label %while.cond.i
+
+while.end.i:
+ %sub.ptr.lhs.cast.i = ptrtoint ptr %a.pn.i to i64
+ %sub.ptr.rhs.cast.i = ptrtoint ptr %val1 to i64
+ %sub.ptr.sub.i = sub i64 %sub.ptr.lhs.cast.i, %sub.ptr.rhs.cast.i
+ br label %_Z9stringlenPKs.exit
+
+_Z9stringlenPKs.exit:
+ %retval.0.i = phi i64 [ %sub.ptr.sub.i, %while.end.i ], [ 0, %entry ]
+ %bool = icmp eq i64 %retval.0.i, 0
+ ret i1 %bool
+}
>From 6ce297fa59bb070820ab4b8cc0d8bab1f6aa550d Mon Sep 17 00:00:00 2001
From: bipmis <biplob.mishra at arm.com>
Date: Fri, 27 Oct 2023 15:33:10 +0100
Subject: [PATCH 2/3] Extend isNonEqual for isNonEqualPointers with Recursive
GEP
---
llvm/lib/Analysis/ValueTracking.cpp | 70 +++++++++++++++++++
.../Analysis/ValueTracking/known-non-equal.ll | 3 +-
.../Analysis/ValueTracking/phi-known-bits.ll | 30 +++-----
llvm/test/Transforms/InstCombine/sub-gep.ll | 3 +-
4 files changed, 82 insertions(+), 24 deletions(-)
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index c303d261107eb19..1fd4ce496fcae9f 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -3141,6 +3141,72 @@ static bool isNonEqualSelect(const Value *V1, const Value *V2, unsigned Depth,
isKnownNonEqual(SI1->getFalseValue(), V2, Depth + 1, Q);
}
+static bool isNonEqualPointersWithRecursiveGEP(const Value *A, const Value *B,
+ unsigned Depth,
+ const SimplifyQuery &Q) {
+ // Where A is a recursive GEP for an incoming value of PHI indicating a
+ // loop. B can be a ptr/GEP.
+ // If the PHI has 2 incoming values, one of it being the recursive GEP A
+ // and other a ptr at same base and at an same/higher offset than B we are
+ // only incrementing the pointer further in loop if offset of recursive GEP is
+ // greater than 0.
+ if (!A->getType()->isPointerTy() || !B->getType()->isPointerTy())
+ return false;
+
+ auto *GEPA = dyn_cast<GEPOperator>(A);
+ // Make sure GEPA pointer operand is a PHI.
+ if (!GEPA || !isa<PHINode>(GEPA->getPointerOperand()))
+ return false;
+
+ // Handle 2 incoming PHI values with one being a recursive GEP.
+ auto *PN = dyn_cast<PHINode>(GEPA->getPointerOperand());
+ if (PN->getNumIncomingValues() == 2) {
+ // Recursive GEP in second incoming value. Always keep Recursive GEP as
+ // FirstInst
+ Value *FirstInst = nullptr, *SecondInst = nullptr;
+ for (unsigned i = 0; i != 2; ++i) {
+ // Check if A is a Recursive GEP in one of the incoming values.
+ if (PN->getIncomingValue(i) == A && GEPA->getNumIndices() == 1 &&
+ isa<Constant>(GEPA->idx_begin())) {
+ FirstInst = PN->getIncomingValue(i);
+ SecondInst = PN->getIncomingValue(1 - i);
+ continue;
+ }
+ }
+ if (FirstInst && SecondInst) {
+ // Other incoming node base should match the B base.
+ // SecondInstOffset >= OffsetB && FirstInstOffset > 0?
+ // SecondInstOffset <= OffsetB && FirstInstOffset < 0?
+ // Is non-equal if above are true.
+ APInt FirstInstOffset(Q.DL.getIndexTypeSizeInBits(FirstInst->getType()),
+ 0);
+ FirstInst = FirstInst->stripAndAccumulateConstantOffsets(
+ Q.DL, FirstInstOffset, /* AllowNonInbounds */ true);
+ APInt SecondInstOffset(Q.DL.getIndexTypeSizeInBits(SecondInst->getType()),
+ 0);
+ SecondInst = SecondInst->stripAndAccumulateConstantOffsets(
+ Q.DL, SecondInstOffset, /* AllowNonInbounds */ true);
+ APInt OffsetB(Q.DL.getIndexTypeSizeInBits(B->getType()), 0);
+ B = B->stripAndAccumulateConstantOffsets(Q.DL, OffsetB,
+ /* AllowNonInbounds */ true);
+ if (SecondInst == B &&
+ ((SecondInstOffset.sge(OffsetB) && FirstInstOffset.sgt(0)) ||
+ (SecondInstOffset.sle(OffsetB) && FirstInstOffset.slt(0))))
+ return true;
+ }
+ }
+ return false;
+}
+
+static bool isNonEqualPointers(const Value *V1, const Value *V2, unsigned Depth,
+ const SimplifyQuery &Q) {
+ // Check if A is a recursive GEP which is not equal to B.
+ if (isNonEqualPointersWithRecursiveGEP(V1, V2, Depth, Q))
+ return true;
+
+ return false;
+}
+
/// Return true if it is known that V1 != V2.
static bool isKnownNonEqual(const Value *V1, const Value *V2, unsigned Depth,
const SimplifyQuery &Q) {
@@ -3194,6 +3260,10 @@ static bool isKnownNonEqual(const Value *V1, const Value *V2, unsigned Depth,
if (isNonEqualSelect(V1, V2, Depth, Q) || isNonEqualSelect(V2, V1, Depth, Q))
return true;
+ if (isNonEqualPointers(V1, V2, Depth, Q) ||
+ isNonEqualPointers(V2, V1, Depth, Q))
+ return true;
+
return false;
}
diff --git a/llvm/test/Analysis/ValueTracking/known-non-equal.ll b/llvm/test/Analysis/ValueTracking/known-non-equal.ll
index bbed4eb92c005fa..365a0ea9bc21dbb 100644
--- a/llvm/test/Analysis/ValueTracking/known-non-equal.ll
+++ b/llvm/test/Analysis/ValueTracking/known-non-equal.ll
@@ -1826,10 +1826,9 @@ define i1 @icmp_recursiveGEP_withPtr(ptr noundef %val1) {
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[BOOL:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
; CHECK: _Z9stringlenPKs.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[BOOL]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ false, [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
;
entry:
diff --git a/llvm/test/Analysis/ValueTracking/phi-known-bits.ll b/llvm/test/Analysis/ValueTracking/phi-known-bits.ll
index 1efb36e41e8088f..1fed11792f13521 100644
--- a/llvm/test/Analysis/ValueTracking/phi-known-bits.ll
+++ b/llvm/test/Analysis/ValueTracking/phi-known-bits.ll
@@ -439,11 +439,9 @@ define i1 @recursiveGEP_withPtr_phisub1(ptr noundef %val1) {
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
; CHECK: _Z9stringlenPKs.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
-; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+; CHECK-NEXT: ret i1 [[CMP_I]]
;
entry:
%cmp.i = icmp eq ptr %val1, null
@@ -480,11 +478,9 @@ define i1 @recursiveGEP_withPtr_phisub1_PhiOperandsCommuted(ptr noundef %val1) {
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
; CHECK: _Z9stringlenPKs.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
-; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+; CHECK-NEXT: ret i1 [[CMP_I]]
;
entry:
%cmp.i = icmp eq ptr %val1, null
@@ -521,11 +517,9 @@ define i1 @recursiveGEP_withPtr_phisub1_SubOperandsCommuted(ptr noundef %val1) {
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
; CHECK: _Z9stringlenPKs.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
-; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+; CHECK-NEXT: ret i1 [[CMP_I]]
;
entry:
%cmp.i = icmp eq ptr %val1, null
@@ -562,11 +556,9 @@ define i1 @recursiveGEP_withPtr_phisub2(ptr noundef %val1) {
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[TMP1:%.*]] = icmp eq ptr [[TEST_0_I]], [[VAL1]]
; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
; CHECK: _Z9stringlenPKs.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
-; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+; CHECK-NEXT: ret i1 [[CMP_I]]
;
entry:
%cmp.i = icmp eq ptr %val1, null
@@ -594,21 +586,19 @@ _Z9stringlenPKs.exit:
define i1 @recursiveGEP_withPtr_phisub3(ptr noundef %val1) {
; CHECK-LABEL: @recursiveGEP_withPtr_phisub3(
; CHECK-NEXT: entry:
-; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1:%.*]], null
+; CHECK-NEXT: [[TEST_VAL1:%.*]] = getelementptr inbounds i8, ptr [[VAL1:%.*]], i64 7
+; CHECK-NEXT: [[CMP_I:%.*]] = icmp eq ptr [[VAL1]], null
; CHECK-NEXT: br i1 [[CMP_I]], label [[_Z9STRINGLENPKS_EXIT:%.*]], label [[WHILE_COND_I:%.*]]
; CHECK: while.cond.i:
-; CHECK-NEXT: [[A_PN_I_IDX:%.*]] = phi i64 [ [[A_PN_I_ADD:%.*]], [[WHILE_COND_I]] ], [ 7, [[ENTRY:%.*]] ]
-; CHECK-NEXT: [[A_PN_I_ADD]] = add nuw nsw i64 [[A_PN_I_IDX]], 1
-; CHECK-NEXT: [[TEST_0_I_PTR:%.*]] = getelementptr inbounds i8, ptr [[VAL1]], i64 [[A_PN_I_ADD]]
-; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I_PTR]], align 2
+; CHECK-NEXT: [[A_PN_I:%.*]] = phi ptr [ [[TEST_0_I:%.*]], [[WHILE_COND_I]] ], [ [[TEST_VAL1]], [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[TEST_0_I]] = getelementptr inbounds i8, ptr [[A_PN_I]], i64 1
+; CHECK-NEXT: [[TMP0:%.*]] = load i8, ptr [[TEST_0_I]], align 2
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP0]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[TMP1:%.*]] = icmp eq i64 [[A_PN_I_ADD]], 5
; CHECK-NEXT: br label [[_Z9STRINGLENPKS_EXIT]]
; CHECK: _Z9stringlenPKs.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP1]], [[WHILE_END_I]] ], [ true, [[ENTRY]] ]
-; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
+; CHECK-NEXT: ret i1 [[CMP_I]]
;
entry:
%test.val1 = getelementptr inbounds i8, ptr %val1, i64 7
diff --git a/llvm/test/Transforms/InstCombine/sub-gep.ll b/llvm/test/Transforms/InstCombine/sub-gep.ll
index a8f8a82e675b026..3997ef44bf328f2 100644
--- a/llvm/test/Transforms/InstCombine/sub-gep.ll
+++ b/llvm/test/Transforms/InstCombine/sub-gep.ll
@@ -386,10 +386,9 @@ define i1 @_gep_phi1(ptr noundef %str1) {
; CHECK-NEXT: [[CMP3_NOT_I:%.*]] = icmp eq i8 [[TMP1]], 0
; CHECK-NEXT: br i1 [[CMP3_NOT_I]], label [[WHILE_END_I:%.*]], label [[WHILE_COND_I]]
; CHECK: while.end.i:
-; CHECK-NEXT: [[TMP2:%.*]] = icmp ne ptr [[TEST_0_I]], [[STR1]]
; CHECK-NEXT: br label [[_Z3FOOPKC_EXIT]]
; CHECK: _Z3fooPKc.exit:
-; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ [[TMP2]], [[WHILE_END_I]] ], [ false, [[LOR_LHS_FALSE_I]] ], [ false, [[ENTRY:%.*]] ]
+; CHECK-NEXT: [[RETVAL_0_I:%.*]] = phi i1 [ true, [[WHILE_END_I]] ], [ false, [[LOR_LHS_FALSE_I]] ], [ false, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i1 [[RETVAL_0_I]]
;
entry:
>From 2cb596572258cdb9a8fc01fc9158ffacc7d3b1dc Mon Sep 17 00:00:00 2001
From: bipmis <biplob.mishra at arm.com>
Date: Mon, 6 Nov 2023 12:57:28 +0000
Subject: [PATCH 3/3] Early return if condition fails for
isNonEqualPointersWithRecursiveGEP
---
llvm/lib/Analysis/ValueTracking.cpp | 67 +++++++++++++++--------------
1 file changed, 34 insertions(+), 33 deletions(-)
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 1fd4ce496fcae9f..98f2b412355013e 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -3160,41 +3160,42 @@ static bool isNonEqualPointersWithRecursiveGEP(const Value *A, const Value *B,
// Handle 2 incoming PHI values with one being a recursive GEP.
auto *PN = dyn_cast<PHINode>(GEPA->getPointerOperand());
- if (PN->getNumIncomingValues() == 2) {
- // Recursive GEP in second incoming value. Always keep Recursive GEP as
- // FirstInst
- Value *FirstInst = nullptr, *SecondInst = nullptr;
- for (unsigned i = 0; i != 2; ++i) {
- // Check if A is a Recursive GEP in one of the incoming values.
- if (PN->getIncomingValue(i) == A && GEPA->getNumIndices() == 1 &&
- isa<Constant>(GEPA->idx_begin())) {
- FirstInst = PN->getIncomingValue(i);
- SecondInst = PN->getIncomingValue(1 - i);
- continue;
- }
- }
- if (FirstInst && SecondInst) {
- // Other incoming node base should match the B base.
- // SecondInstOffset >= OffsetB && FirstInstOffset > 0?
- // SecondInstOffset <= OffsetB && FirstInstOffset < 0?
- // Is non-equal if above are true.
- APInt FirstInstOffset(Q.DL.getIndexTypeSizeInBits(FirstInst->getType()),
- 0);
- FirstInst = FirstInst->stripAndAccumulateConstantOffsets(
- Q.DL, FirstInstOffset, /* AllowNonInbounds */ true);
- APInt SecondInstOffset(Q.DL.getIndexTypeSizeInBits(SecondInst->getType()),
- 0);
- SecondInst = SecondInst->stripAndAccumulateConstantOffsets(
- Q.DL, SecondInstOffset, /* AllowNonInbounds */ true);
- APInt OffsetB(Q.DL.getIndexTypeSizeInBits(B->getType()), 0);
- B = B->stripAndAccumulateConstantOffsets(Q.DL, OffsetB,
- /* AllowNonInbounds */ true);
- if (SecondInst == B &&
- ((SecondInstOffset.sge(OffsetB) && FirstInstOffset.sgt(0)) ||
- (SecondInstOffset.sle(OffsetB) && FirstInstOffset.slt(0))))
- return true;
+ if (PN->getNumIncomingValues() != 2)
+ return false;
+
+ // Recursive GEP in second incoming value. Always keep Recursive GEP as
+ // FirstInst
+ Value *FirstInst = nullptr, *SecondInst = nullptr;
+ for (unsigned i = 0; i != 2; ++i) {
+ // Check if A is a Recursive GEP in one of the incoming values.
+ if (PN->getIncomingValue(i) == A && GEPA->getNumIndices() == 1 &&
+ isa<Constant>(GEPA->idx_begin())) {
+ FirstInst = PN->getIncomingValue(i);
+ SecondInst = PN->getIncomingValue(1 - i);
+ continue;
}
}
+ if (FirstInst == nullptr || SecondInst == nullptr)
+ return false;
+
+ // Other incoming node base should match the B base.
+ // SecondInstOffset >= OffsetB && FirstInstOffset > 0?
+ // SecondInstOffset <= OffsetB && FirstInstOffset < 0?
+ // Is non-equal if above are true.
+ APInt FirstInstOffset(Q.DL.getIndexTypeSizeInBits(FirstInst->getType()), 0);
+ FirstInst = FirstInst->stripAndAccumulateConstantOffsets(
+ Q.DL, FirstInstOffset, /* AllowNonInbounds */ true);
+ APInt SecondInstOffset(Q.DL.getIndexTypeSizeInBits(SecondInst->getType()), 0);
+ SecondInst = SecondInst->stripAndAccumulateConstantOffsets(
+ Q.DL, SecondInstOffset, /* AllowNonInbounds */ true);
+ APInt OffsetB(Q.DL.getIndexTypeSizeInBits(B->getType()), 0);
+ B = B->stripAndAccumulateConstantOffsets(Q.DL, OffsetB,
+ /* AllowNonInbounds */ true);
+ if (SecondInst == B &&
+ ((SecondInstOffset.sge(OffsetB) && FirstInstOffset.sgt(0)) ||
+ (SecondInstOffset.sle(OffsetB) && FirstInstOffset.slt(0))))
+ return true;
+
return false;
}
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