diff --git a/llvm/lib/Target/X86/X86LegalizerInfo.cpp b/llvm/lib/Target/X86/X86LegalizerInfo.cpp
--- a/llvm/lib/Target/X86/X86LegalizerInfo.cpp
+++ b/llvm/lib/Target/X86/X86LegalizerInfo.cpp
@@ -72,6 +72,10 @@
   setLegalizerInfoAVX512DQ();
   setLegalizerInfoAVX512BW();
 
+  const LLT s16 = LLT::scalar(16);
+  const LLT s32 = LLT::scalar(32);
+  const LLT s64 = LLT::scalar(64);
+
   getActionDefinitionsBuilder(G_INTRINSIC_ROUNDEVEN)
     .scalarize(0)
     .minScalar(0, LLT::scalar(32))
@@ -93,6 +97,41 @@
 
   getActionDefinitionsBuilder({G_MEMCPY, G_MEMMOVE, G_MEMSET}).libcall();
 
+
+  if (Subtarget.is64Bit()) {
+    if (Subtarget.hasPOPCNT()) {
+      // popcount
+      getActionDefinitionsBuilder(G_CTPOP)
+        .legalFor({{s16, s16}, {s32, s32}, {s64, s64}})
+        .widenScalarToNextPow2(1, /*Min=*/16)
+        .clampScalar(1, s16, s64);
+    }
+
+    if (Subtarget.hasLZCNT()) {
+      // count leading zeros (LZCNT)
+      getActionDefinitionsBuilder(G_CTLZ)
+        .legalFor({{s16, s16}, {s32, s32}, {s64, s64}})
+        .widenScalarToNextPow2(1, /*Min=*/16)
+        .clampScalar(1, s16, s64);
+    }
+  } else { // 32-bit
+    if (Subtarget.hasPOPCNT()) {
+      // popcount
+      getActionDefinitionsBuilder(G_CTPOP)
+        .legalFor({{s16, s16}, {s32, s32}})
+        .widenScalarToNextPow2(1, /*Min=*/16)
+        .clampScalar(1, s16, s32);
+    }
+
+    if (Subtarget.hasLZCNT()) {
+      // count leading zeros (LZCNT)
+      getActionDefinitionsBuilder(G_CTLZ)
+        .legalFor({{s16, s16}, {s32, s32}})
+        .widenScalarToNextPow2(1, /*Min=*/16)
+        .clampScalar(1, s16, s32);
+    }
+  }
+
   LegacyInfo.computeTables();
   verify(*STI.getInstrInfo());
 }
@@ -288,22 +327,6 @@
   LegacyInfo.setAction({G_MERGE_VALUES, 1, s128}, LegacyLegalizeActions::Legal);
   LegacyInfo.setAction({G_UNMERGE_VALUES, s128}, LegacyLegalizeActions::Legal);
 
-  if (Subtarget.hasPOPCNT()) {
-    // popcount
-    getActionDefinitionsBuilder(G_CTPOP)
-      .legalFor({{s16, s16}, {s32, s32}, {s64, s64}})
-      .widenScalarToNextPow2(1, /*Min=*/16)
-      .clampScalar(1, s16, s64);
-  }
-
-  if (Subtarget.hasLZCNT()) {
-    // count leading zeros (LZCNT)
-    getActionDefinitionsBuilder(G_CTLZ)
-      .legalFor({{s16, s16}, {s32, s32}, {s64, s64}})
-      .widenScalarToNextPow2(1, /*Min=*/16)
-      .clampScalar(1, s16, s64);
-  }
-
 }
 
 void X86LegalizerInfo::setLegalizerInfoSSE1() {
diff --git a/llvm/test/CodeGen/X86/GlobalISel/legalize-ctpop-32.mir b/llvm/test/CodeGen/X86/GlobalISel/legalize-ctpop-32.mir
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/X86/GlobalISel/legalize-ctpop-32.mir
@@ -0,0 +1,70 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 2
+# RUN: llc -mtriple=i386-linux-gnu -mattr=+popcnt -run-pass=legalizer %s -o - | FileCheck %s
+
+# test popcount for s8, s16, and s32
+
+---
+name:            test_ctpop8
+alignment:       16
+legalized:       false
+regBankSelected: false
+registers:
+  - { id: 0, class: _, preferred-register: '' }
+  - { id: 1, class: _, preferred-register: '' }
+body:             |
+  bb.1:
+    ; CHECK-LABEL: name: test_ctpop8
+    ; CHECK: [[DEF:%[0-9]+]]:_(s8) = IMPLICIT_DEF
+    ; CHECK-NEXT: [[ZEXT:%[0-9]+]]:_(s16) = G_ZEXT [[DEF]](s8)
+    ; CHECK-NEXT: [[CTPOP:%[0-9]+]]:_(s16) = G_CTPOP [[ZEXT]](s16)
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s8) = G_TRUNC [[CTPOP]](s16)
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s8) = COPY [[TRUNC]](s8)
+    ; CHECK-NEXT: RET 0, implicit [[COPY]](s8)
+    %0:_(s8) = IMPLICIT_DEF
+    %1:_(s8) = G_CTPOP %0
+    %2:_(s8) = COPY %1(s8)
+    RET 0, implicit %2
+
+...
+---
+name:            test_ctpop32
+alignment:       16
+legalized:       false
+regBankSelected: false
+registers:
+  - { id: 0, class: _, preferred-register: '' }
+  - { id: 1, class: _, preferred-register: '' }
+body:             |
+  bb.1:
+    ; CHECK-LABEL: name: test_ctpop32
+    ; CHECK: [[DEF:%[0-9]+]]:_(s32) = IMPLICIT_DEF
+    ; CHECK-NEXT: [[CTPOP:%[0-9]+]]:_(s32) = G_CTPOP [[DEF]](s32)
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s32) = COPY [[CTPOP]](s32)
+    ; CHECK-NEXT: RET 0, implicit [[COPY]](s32)
+    %0:_(s32) = IMPLICIT_DEF
+    %1:_(s32) = G_CTPOP %0
+    %2:_(s32) = COPY %1(s32)
+    RET 0, implicit %2
+
+...
+---
+name:            test_ctpop16
+alignment:       16
+legalized:       false
+regBankSelected: false
+registers:
+  - { id: 0, class: _, preferred-register: '' }
+  - { id: 1, class: _, preferred-register: '' }
+body:             |
+  bb.1:
+    ; CHECK-LABEL: name: test_ctpop16
+    ; CHECK: [[DEF:%[0-9]+]]:_(s16) = IMPLICIT_DEF
+    ; CHECK-NEXT: [[CTPOP:%[0-9]+]]:_(s16) = G_CTPOP [[DEF]](s16)
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s16) = COPY [[CTPOP]](s16)
+    ; CHECK-NEXT: RET 0, implicit [[COPY]](s16)
+    %0:_(s16) = IMPLICIT_DEF
+    %1:_(s16) = G_CTPOP %0
+    %2:_(s16) = COPY %1(s16)
+    RET 0, implicit %2
+
+...
diff --git a/llvm/test/CodeGen/X86/GlobalISel/legalize-leading-zeros-32.mir b/llvm/test/CodeGen/X86/GlobalISel/legalize-leading-zeros-32.mir
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/X86/GlobalISel/legalize-leading-zeros-32.mir
@@ -0,0 +1,72 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 2
+# RUN: llc -mtriple=i386-linux-gnu -mattr=+lzcnt -run-pass=legalizer %s -o - | FileCheck %s
+
+# test count leading zeros for s8, s16, and s32
+
+---
+name:            test_ctlz8
+alignment:       16
+legalized:       false
+regBankSelected: false
+registers:
+  - { id: 0, class: _, preferred-register: '' }
+  - { id: 1, class: _, preferred-register: '' }
+body:             |
+  bb.1:
+    ; CHECK-LABEL: name: test_ctlz8
+    ; CHECK: [[DEF:%[0-9]+]]:_(s8) = IMPLICIT_DEF
+    ; CHECK-NEXT: [[ZEXT:%[0-9]+]]:_(s16) = G_ZEXT [[DEF]](s8)
+    ; CHECK-NEXT: [[CTLZ:%[0-9]+]]:_(s16) = G_CTLZ [[ZEXT]](s16)
+    ; CHECK-NEXT: [[C:%[0-9]+]]:_(s16) = G_CONSTANT i16 8
+    ; CHECK-NEXT: [[SUB:%[0-9]+]]:_(s16) = G_SUB [[CTLZ]], [[C]]
+    ; CHECK-NEXT: [[TRUNC:%[0-9]+]]:_(s8) = G_TRUNC [[SUB]](s16)
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s8) = COPY [[TRUNC]](s8)
+    ; CHECK-NEXT: RET 0, implicit [[COPY]](s8)
+    %0:_(s8) = IMPLICIT_DEF
+    %1:_(s8) = G_CTLZ %0
+    %2:_(s8) = COPY %1(s8)
+    RET 0, implicit %2
+
+...
+---
+name:            test_ctlz32
+alignment:       16
+legalized:       false
+regBankSelected: false
+registers:
+  - { id: 0, class: _, preferred-register: '' }
+  - { id: 1, class: _, preferred-register: '' }
+body:             |
+  bb.1:
+    ; CHECK-LABEL: name: test_ctlz32
+    ; CHECK: [[DEF:%[0-9]+]]:_(s32) = IMPLICIT_DEF
+    ; CHECK-NEXT: [[CTLZ:%[0-9]+]]:_(s32) = G_CTLZ [[DEF]](s32)
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s32) = COPY [[CTLZ]](s32)
+    ; CHECK-NEXT: RET 0, implicit [[COPY]](s32)
+    %0:_(s32) = IMPLICIT_DEF
+    %1:_(s32) = G_CTLZ %0
+    %2:_(s32) = COPY %1(s32)
+    RET 0, implicit %2
+
+...
+---
+name:            test_ctlz16
+alignment:       16
+legalized:       false
+regBankSelected: false
+registers:
+  - { id: 0, class: _, preferred-register: '' }
+  - { id: 1, class: _, preferred-register: '' }
+body:             |
+  bb.1:
+    ; CHECK-LABEL: name: test_ctlz16
+    ; CHECK: [[DEF:%[0-9]+]]:_(s16) = IMPLICIT_DEF
+    ; CHECK-NEXT: [[CTLZ:%[0-9]+]]:_(s16) = G_CTLZ [[DEF]](s16)
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:_(s16) = COPY [[CTLZ]](s16)
+    ; CHECK-NEXT: RET 0, implicit [[COPY]](s16)
+    %0:_(s16) = IMPLICIT_DEF
+    %1:_(s16) = G_CTLZ %0
+    %2:_(s16) = COPY %1(s16)
+    RET 0, implicit %2
+
+...