Index: llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp
===================================================================
--- llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp
+++ llvm/lib/Target/AArch64/GISel/AArch64LegalizerInfo.cpp
@@ -490,8 +490,8 @@
 
   getActionDefinitionsBuilder(G_PTRTOINT)
       .legalForCartesianProduct({s1, s8, s16, s32, s64}, {p0})
-      .maxScalar(0, s64)
-      .widenScalarToNextPow2(0, /*Min*/ 8);
+      .widenScalarToNextPow2(0)
+      .clampScalar(0, s64, s64);
 
   getActionDefinitionsBuilder(G_INTTOPTR)
       .unsupportedIf([&](const LegalityQuery &Query) {
Index: llvm/test/CodeGen/AArch64/GlobalISel/legalize-ptrtoint.mir
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/AArch64/GlobalISel/legalize-ptrtoint.mir
@@ -0,0 +1,116 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -mtriple aarch64 -run-pass=legalizer -verify-machineinstrs -o - %s  | FileCheck %s
+
+...
+---
+name: p0_s64
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: p0_s64
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: %int:_(s64) = G_PTRTOINT %ptr(p0)
+    ; CHECK: $x0 = COPY %int(s64)
+    ; CHECK: RET_ReallyLR implicit $x0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s64) = G_PTRTOINT %ptr
+    $x0 = COPY %int
+    RET_ReallyLR implicit $x0
+...
+---
+name: p0_s32
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: p0_s32
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: %int:_(s32) = G_PTRTOINT %ptr(p0)
+    ; CHECK: $w0 = COPY %int(s32)
+    ; CHECK: RET_ReallyLR implicit $w0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s32) = G_PTRTOINT %ptr
+    $w0 = COPY %int
+    RET_ReallyLR implicit $w0
+...
+---
+name: p0_s16
+body: |
+  bb.0:
+    liveins: $x0, $h0
+    ; CHECK-LABEL: name: p0_s16
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: %int:_(s16) = G_PTRTOINT %ptr(p0)
+    ; CHECK: $h0 = COPY %int(s16)
+    ; CHECK: RET_ReallyLR implicit $h0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s16) = G_PTRTOINT %ptr
+    $h0 = COPY %int
+    RET_ReallyLR implicit $h0
+...
+---
+name: p0_s8
+body: |
+  bb.0:
+    liveins: $x0, $b0
+    ; CHECK-LABEL: name: p0_s8
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: %int:_(s8) = G_PTRTOINT %ptr(p0)
+    ; CHECK: $b0 = COPY %int(s8)
+    ; CHECK: RET_ReallyLR implicit $b0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s8) = G_PTRTOINT %ptr
+    $b0 = COPY %int
+    RET_ReallyLR implicit $b0
+...
+---
+name: p0_s1
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: p0_s1
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: %int:_(s1) = G_PTRTOINT %ptr(p0)
+    ; CHECK: %ext:_(s32) = G_ZEXT %int(s1)
+    ; CHECK: $w0 = COPY %ext(s32)
+    ; CHECK: RET_ReallyLR implicit $w0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s1) = G_PTRTOINT %ptr
+    %ext:_(s32) = G_ZEXT %int
+    $w0 = COPY %ext
+    RET_ReallyLR implicit $w0
+...
+---
+name: p0_s128
+body: |
+  bb.0:
+    liveins: $x0, $q0
+    ; CHECK-LABEL: name: p0_s128
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: [[PTRTOINT:%[0-9]+]]:_(s64) = G_PTRTOINT %ptr(p0)
+    ; CHECK: [[C:%[0-9]+]]:_(s64) = G_CONSTANT i64 0
+    ; CHECK: %int:_(s128) = G_MERGE_VALUES [[PTRTOINT]](s64), [[C]](s64)
+    ; CHECK: $q0 = COPY %int(s128)
+    ; CHECK: RET_ReallyLR implicit $q0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s128) = G_PTRTOINT %ptr
+    $q0 = COPY %int
+    RET_ReallyLR implicit $q0
+...
+---
+name: p0_s88
+body: |
+  bb.0:
+    liveins: $x0
+    ; CHECK-LABEL: name: p0_s88
+    ; CHECK: %ptr:_(p0) = COPY $x0
+    ; CHECK: [[PTRTOINT:%[0-9]+]]:_(s64) = G_PTRTOINT %ptr(p0)
+    ; CHECK: [[C:%[0-9]+]]:_(s64) = G_CONSTANT i64 0
+    ; CHECK: %trunc:_(s32) = G_TRUNC [[PTRTOINT]](s64)
+    ; CHECK: $w0 = COPY %trunc(s32)
+    ; CHECK: RET_ReallyLR implicit $w0
+    %ptr:_(p0) = COPY $x0
+    %int:_(s88) = G_PTRTOINT %ptr
+    %trunc:_(s32) = G_TRUNC %int
+    $w0 = COPY %trunc
+    RET_ReallyLR implicit $w0
+...