diff --git a/llvm/test/Transforms/InstCombine/bit_ceil.ll b/llvm/test/Transforms/InstCombine/bit_ceil.ll
index 440ab3d697e59d..aa98896aac5493 100644
--- a/llvm/test/Transforms/InstCombine/bit_ceil.ll
+++ b/llvm/test/Transforms/InstCombine/bit_ceil.ll
@@ -1,6 +1,7 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt < %s -passes=instcombine -S | FileCheck %s
 
+; std::bit_ceil<uint32_t>(x)
 define i32 @bit_ceil_32(i32 %x) {
 ; CHECK-LABEL: @bit_ceil_32(
 ; CHECK-NEXT:    [[DEC:%.*]] = add i32 [[X:%.*]], -1
@@ -20,6 +21,7 @@ define i32 @bit_ceil_32(i32 %x) {
   ret i32 %sel
 }
 
+; std::bit_ceil<uint64_t>(x)
 define i64 @bit_ceil_64(i64 %x) {
 ; CHECK-LABEL: @bit_ceil_64(
 ; CHECK-NEXT:    [[DEC:%.*]] = add i64 [[X:%.*]], -1
@@ -39,5 +41,116 @@ define i64 @bit_ceil_64(i64 %x) {
   ret i64 %sel
 }
 
+; std::bit_ceil<uint32_t>(x - 1)
+define i32 @bit_ceil_32_minus_1(i32 %x) {
+; CHECK-LABEL: @bit_ceil_32_minus_1(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[SUB:%.*]] = add i32 [[X:%.*]], -2
+; CHECK-NEXT:    [[CTLZ:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[SUB]], i1 false), !range [[RNG0]]
+; CHECK-NEXT:    [[SUB2:%.*]] = sub nuw nsw i32 32, [[CTLZ]]
+; CHECK-NEXT:    [[SHL:%.*]] = shl nuw i32 1, [[SUB2]]
+; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[X]], -3
+; CHECK-NEXT:    [[ULT:%.*]] = icmp ult i32 [[ADD]], -2
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[ULT]], i32 [[SHL]], i32 1
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+entry:
+  %sub = add i32 %x, -2
+  %ctlz = tail call i32 @llvm.ctlz.i32(i32 %sub, i1 false)
+  %sub2 = sub nuw nsw i32 32, %ctlz
+  %shl = shl nuw i32 1, %sub2
+  %add = add i32 %x, -3
+  %ult = icmp ult i32 %add, -2
+  %sel = select i1 %ult, i32 %shl, i32 1
+  ret i32 %sel
+}
+
+; std::bit_ceil<uint32_t>(x + 1)
+define i32 @bit_ceil_32_plus_1(i32 %x) {
+; CHECK-LABEL: @bit_ceil_32_plus_1(
+; CHECK-NEXT:    [[CTLZ:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[X:%.*]], i1 false), !range [[RNG0]]
+; CHECK-NEXT:    [[SUB:%.*]] = sub nuw nsw i32 32, [[CTLZ]]
+; CHECK-NEXT:    [[SHL:%.*]] = shl nuw i32 1, [[SUB]]
+; CHECK-NEXT:    [[DEC:%.*]] = add i32 [[X]], -1
+; CHECK-NEXT:    [[ULT:%.*]] = icmp ult i32 [[DEC]], -2
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[ULT]], i32 [[SHL]], i32 1
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+  %ctlz = tail call i32 @llvm.ctlz.i32(i32 %x, i1 false)
+  %sub = sub i32 32, %ctlz
+  %shl = shl i32 1, %sub
+  %dec = add i32 %x, -1
+  %ult = icmp ult i32 %dec, -2
+  %sel = select i1 %ult, i32 %shl, i32 1
+  ret i32 %sel
+}
+
+define i32 @bit_ceil_plus_2(i32 %x) {
+; CHECK-LABEL: @bit_ceil_plus_2(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[SUB:%.*]] = add i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CTLZ:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[SUB]], i1 false), !range [[RNG0]]
+; CHECK-NEXT:    [[SUB2:%.*]] = sub nuw nsw i32 32, [[CTLZ]]
+; CHECK-NEXT:    [[SHL:%.*]] = shl nuw i32 1, [[SUB2]]
+; CHECK-NEXT:    [[ULT:%.*]] = icmp ult i32 [[X]], -2
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[ULT]], i32 [[SHL]], i32 1
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+entry:
+  %sub = add i32 %x, 1
+  %ctlz = tail call i32 @llvm.ctlz.i32(i32 %sub, i1 false)
+  %sub2 = sub nuw nsw i32 32, %ctlz
+  %shl = shl nuw i32 1, %sub2
+  %ult = icmp ult i32 %x, -2
+  %sel = select i1 %ult, i32 %shl, i32 1
+  ret i32 %sel
+}
+
+; std::bit_ceil<uint32_t>(-x)
+define i32 @bit_ceil_32_neg(i32 %x) {
+; CHECK-LABEL: @bit_ceil_32_neg(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[SUB:%.*]] = xor i32 [[X:%.*]], -1
+; CHECK-NEXT:    [[CTLZ:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[SUB]], i1 false), !range [[RNG0]]
+; CHECK-NEXT:    [[SUB2:%.*]] = sub nuw nsw i32 32, [[CTLZ]]
+; CHECK-NEXT:    [[SHL:%.*]] = shl nuw i32 1, [[SUB2]]
+; CHECK-NEXT:    [[NOTSUB:%.*]] = add i32 [[X]], -1
+; CHECK-NEXT:    [[ULT:%.*]] = icmp ult i32 [[NOTSUB]], -2
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[ULT]], i32 [[SHL]], i32 1
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+entry:
+  %sub = xor i32 %x, -1
+  %ctlz = tail call i32 @llvm.ctlz.i32(i32 %sub, i1 false)
+  %sub2 = sub nuw nsw i32 32, %ctlz
+  %shl = shl nuw i32 1, %sub2
+  %notsub = add i32 %x, -1
+  %ult = icmp ult i32 %notsub, -2
+  %sel = select i1 %ult, i32 %shl, i32 1
+  ret i32 %sel
+}
+
+; std::bit_ceil<uint32_t>(~x)
+define i32 @bit_ceil_not(i32 %x) {
+; CHECK-LABEL: @bit_ceil_not(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[SUB:%.*]] = sub i32 -2, [[X:%.*]]
+; CHECK-NEXT:    [[CTLZ:%.*]] = tail call i32 @llvm.ctlz.i32(i32 [[SUB]], i1 false), !range [[RNG0]]
+; CHECK-NEXT:    [[SUB2:%.*]] = sub nuw nsw i32 32, [[CTLZ]]
+; CHECK-NEXT:    [[SHL:%.*]] = shl nuw i32 1, [[SUB2]]
+; CHECK-NEXT:    [[ULT:%.*]] = icmp ult i32 [[X]], -2
+; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[ULT]], i32 [[SHL]], i32 1
+; CHECK-NEXT:    ret i32 [[SEL]]
+;
+entry:
+  %sub = sub i32 -2, %x
+  %ctlz = tail call i32 @llvm.ctlz.i32(i32 %sub, i1 false)
+  %sub2 = sub nuw nsw i32 32, %ctlz
+  %shl = shl nuw i32 1, %sub2
+  %ult = icmp ult i32 %x, -2
+  %sel = select i1 %ult, i32 %shl, i32 1
+  ret i32 %sel
+}
+
 declare i32 @llvm.ctlz.i32(i32, i1 immarg)
 declare i64 @llvm.ctlz.i64(i64, i1 immarg)