diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
--- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -1534,7 +1534,8 @@
   }
 
   // pow(2.0 ** n, x) -> exp2(n * x)
-  if (hasFloatFn(TLI, Ty, LibFunc_exp2, LibFunc_exp2f, LibFunc_exp2l)) {
+  if (Pow->doesNotAccessMemory() ||
+      hasFloatFn(TLI, Ty, LibFunc_exp2, LibFunc_exp2f, LibFunc_exp2l)) {
     APFloat BaseR = APFloat(1.0);
     BaseR.convert(BaseF->getSemantics(), APFloat::rmTowardZero, &Ignored);
     BaseR = BaseR / *BaseF;
diff --git a/llvm/test/Transforms/InstCombine/pow-1.ll b/llvm/test/Transforms/InstCombine/pow-1.ll
--- a/llvm/test/Transforms/InstCombine/pow-1.ll
+++ b/llvm/test/Transforms/InstCombine/pow-1.ll
@@ -107,13 +107,8 @@
 
 define <2 x float> @test_simplify3v(<2 x float> %x) {
 ; CHECK-LABEL: @test_simplify3v(
-; ANY-NEXT:    [[EXP2:%.*]] = call <2 x float> @llvm.exp2.v2f32(<2 x float> [[X:%.*]])
-; ANY-NEXT:    ret <2 x float> [[EXP2]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 2.000000e+00, float 2.000000e+00>, <2 x float> [[X:%.*]])
-; MSVC-NEXT:   ret <2 x float> [[POW]]
-; TODO: should be able to simplify llvm.pow to llvm.exp2 even without libcalls
-; NOLIB-NEXT:    [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 2.000000e+00, float 2.000000e+00>, <2 x float> [[X:%.*]])
-; NOLIB-NEXT:    ret <2 x float> [[POW]]
+; CHECK-NEXT:    [[EXP2:%.*]] = call <2 x float> @llvm.exp2.v2f32(<2 x float> [[X:%.*]])
+; CHECK-NEXT:    ret <2 x float> [[EXP2]]
 ;
   %retval = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 2.0, float 2.0>, <2 x float> %x)
   ret <2 x float> %retval
@@ -121,14 +116,9 @@
 
 define <2 x double> @test_simplify3vn(<2 x double> %x) {
 ; CHECK-LABEL: @test_simplify3vn(
-; ANY-NEXT:    [[MUL:%.*]] = fmul <2 x double> [[X:%.*]], <double 2.000000e+00, double 2.000000e+00>
-; ANY-NEXT:    [[EXP2:%.*]] = call <2 x double> @llvm.exp2.v2f64(<2 x double> [[MUL]])
-; ANY-NEXT:    ret <2 x double> [[EXP2]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 4.000000e+00, double 4.000000e+00>, <2 x double> [[X:%.*]])
-; MSVC-NEXT:   ret <2 x double> [[POW]]
-; TODO: should be able to simplify llvm.pow to llvm.exp2 even without libcalls
-; NOLIB-NEXT:    [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 4.000000e+00, double 4.000000e+00>, <2 x double> [[X:%.*]])
-; NOLIB-NEXT:    ret <2 x double> [[POW]]
+; CHECK-NEXT:    [[MUL:%.*]] = fmul <2 x double> [[X:%.*]], <double 2.000000e+00, double 2.000000e+00>
+; CHECK-NEXT:    [[EXP2:%.*]] = call <2 x double> @llvm.exp2.v2f64(<2 x double> [[MUL]])
+; CHECK-NEXT:    ret <2 x double> [[EXP2]]
 ;
   %retval = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 4.0, double 4.0>, <2 x double> %x)
   ret <2 x double> %retval
@@ -174,13 +164,8 @@
 
 define <2 x double> @test_simplify4v(<2 x double> %x) {
 ; CHECK-LABEL: @test_simplify4v(
-; ANY-NEXT:    [[EXP2:%.*]] = call <2 x double> @llvm.exp2.v2f64(<2 x double> [[X:%.*]])
-; ANY-NEXT:    ret <2 x double> [[EXP2]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 2.000000e+00, double 2.000000e+00>, <2 x double> [[X:%.*]])
-; MSVC-NEXT:   ret <2 x double> [[POW]]
-; TODO: should be able to simplify llvm.pow to llvm.exp2 even without libcalls
-; NOLIB-NEXT:    [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 2.000000e+00, double 2.000000e+00>, <2 x double> [[X:%.*]])
-; NOLIB-NEXT:    ret <2 x double> [[POW]]
+; CHECK-NEXT:    [[EXP2:%.*]] = call <2 x double> @llvm.exp2.v2f64(<2 x double> [[X:%.*]])
+; CHECK-NEXT:    ret <2 x double> [[EXP2]]
 ;
   %retval = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 2.0, double 2.0>, <2 x double> %x)
   ret <2 x double> %retval
@@ -188,14 +173,9 @@
 
 define <2 x float> @test_simplify4vn(<2 x float> %x) {
 ; CHECK-LABEL: @test_simplify4vn(
-; ANY-NEXT:    [[MUL:%.*]] = fneg <2 x float> [[X:%.*]]
-; ANY-NEXT:    [[EXP2:%.*]] = call <2 x float> @llvm.exp2.v2f32(<2 x float> [[MUL]])
-; ANY-NEXT:    ret <2 x float> [[EXP2]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 5.000000e-01, float 5.000000e-01>, <2 x float> [[X:%.*]])
-; MSVC-NEXT:   ret <2 x float> [[POW]]
-; TODO: should be able to simplify llvm.pow to llvm.exp2 even without libcalls
-; NOLIB-NEXT:    [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 5.000000e-01, float 5.000000e-01>, <2 x float> [[X:%.*]])
-; NOLIB-NEXT:    ret <2 x float> [[POW]]
+; CHECK-NEXT:    [[MUL:%.*]] = fneg <2 x float> [[X:%.*]]
+; CHECK-NEXT:    [[EXP2:%.*]] = call <2 x float> @llvm.exp2.v2f32(<2 x float> [[MUL]])
+; CHECK-NEXT:    ret <2 x float> [[EXP2]]
 ;
   %retval = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 0.5, float 0.5>, <2 x float> %x)
   ret <2 x float> %retval