Index: lib/Transforms/Utils/SimplifyLibCalls.cpp
===================================================================
--- lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -1529,8 +1529,10 @@
   bool AllowApprox = Pow->hasApproxFunc();
   bool Ignored;
 
-  // Bail out if simplifying libcalls to pow() is disabled.
-  if (!hasFloatFn(TLI, Ty, LibFunc_pow, LibFunc_powf, LibFunc_powl))
+  // Bail out if simplifying libcalls to pow() is disabled, and the present call
+  // is pow() rather than llvm.pow.
+  if (!Callee->isIntrinsic() &&
+      !hasFloatFn(TLI, Ty, LibFunc_pow, LibFunc_powf, LibFunc_powl))
     return nullptr;
 
   // Propagate the math semantics from the call to any created instructions.
Index: test/Transforms/InstCombine/pow-1.ll
===================================================================
--- test/Transforms/InstCombine/pow-1.ll
+++ test/Transforms/InstCombine/pow-1.ll
@@ -38,9 +38,7 @@
 
 define <2 x float> @test_simplify1v(<2 x float> %x) {
 ; CHECK-LABEL: @test_simplify1v(
-; ANY-NEXT:    ret <2 x float> <float 1.000000e+00, float 1.000000e+00>
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 1.000000e+00, float 1.000000e+00>, <2 x float> [[X:%.*]])
-; MSVC-NEXT:   ret <2 x float> [[POW]]
+; CHECK-NEXT:  ret <2 x float> <float 1.000000e+00, float 1.000000e+00>
 ;
   %retval = call <2 x float> @llvm.pow.v2f32(<2 x float> <float 1.0, float 1.0>, <2 x float> %x)
   ret <2 x float> %retval
@@ -56,9 +54,7 @@
 
 define <2 x double> @test_simplify2v(<2 x double> %x) {
 ; CHECK-LABEL: @test_simplify2v(
-; ANY-NEXT:    ret <2 x double> <double 1.000000e+00, double 1.000000e+00>
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 1.000000e+00, double 1.000000e+00>, <2 x double> [[X:%.*]])
-; MSVC-NEXT:   ret <2 x double> [[POW]]
+; CHECK-NEXT:  ret <2 x double> <double 1.000000e+00, double 1.000000e+00>
 ;
   %retval = call <2 x double> @llvm.pow.v2f64(<2 x double> <double 1.0, double 1.0>, <2 x double> %x)
   ret <2 x double> %retval
@@ -117,7 +113,6 @@
 ; 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]]
 ;
   %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
@@ -198,9 +193,7 @@
 
 define <2 x float> @test_simplify5v(<2 x float> %x) {
 ; CHECK-LABEL: @test_simplify5v(
-; ANY-NEXT:    ret <2 x float> <float 1.000000e+00, float 1.000000e+00>
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> [[X:%.*]], <2 x float> zeroinitializer)
-; MSVC-NEXT:   ret <2 x float> [[POW]]
+; CHECK-NEXT:  ret <2 x float> <float 1.000000e+00, float 1.000000e+00>
 ;
   %retval = call <2 x float> @llvm.pow.v2f32(<2 x float> %x, <2 x float> <float 0.0, float 0.0>)
   ret <2 x float> %retval
@@ -216,9 +209,7 @@
 
 define <2 x double> @test_simplify6v(<2 x double> %x) {
 ; CHECK-LABEL: @test_simplify6v(
-; ANY-NEXT:    ret <2 x double> <double 1.000000e+00, double 1.000000e+00>
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> [[X:%.*]], <2 x double> zeroinitializer)
-; MSVC-NEXT:   ret <2 x double> [[POW]]
+; CHECK-NEXT:  ret <2 x double> <double 1.000000e+00, double 1.000000e+00>
 ;
   %retval = call <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double 0.0, double 0.0>)
   ret <2 x double> %retval
@@ -306,9 +297,7 @@
 
 define <2 x float> @test_simplify11v(<2 x float> %x) {
 ; CHECK-LABEL: @test_simplify11v(
-; ANY-NEXT:    ret <2 x float> [[X:%.*]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> [[X:%.*]], <2 x float> <float 1.000000e+00, float 1.000000e+00>)
-; MSVC-NEXT:   ret <2 x float> [[POW]]
+; CHECK-NEXT:  ret <2 x float> [[X:%.*]]
 ;
   %retval = call <2 x float> @llvm.pow.v2f32(<2 x float> %x, <2 x float> <float 1.0, float 1.0>)
   ret <2 x float> %retval
@@ -324,9 +313,7 @@
 
 define <2 x double> @test_simplify12v(<2 x double> %x) {
 ; CHECK-LABEL: @test_simplify12v(
-; ANY-NEXT:    ret <2 x double> [[X:%.*]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> [[X:%.*]], <2 x double> <double 1.000000e+00, double 1.000000e+00>)
-; MSVC-NEXT:   ret <2 x double> [[POW]]
+; CHECK-NEXT:    ret <2 x double> [[X:%.*]]
 ;
   %retval = call <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double 1.0, double 1.0>)
   ret <2 x double> %retval
@@ -353,10 +340,8 @@
 
 define <2 x float> @pow2_strictv(<2 x float> %x) {
 ; CHECK-LABEL: @pow2_strictv(
-; ANY-NEXT:    [[SQUARE:%.*]] = fmul <2 x float> [[X:%.*]], [[X]]
-; ANY-NEXT:    ret <2 x float> [[SQUARE]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> [[X:%.*]], <2 x float> <float 2.000000e+00, float 2.000000e+00>)
-; MSVC-NEXT:   ret <2 x float> [[POW]]
+; CHECK-NEXT:  [[SQUARE:%.*]] = fmul <2 x float> [[X:%.*]], [[X]]
+; CHECK-NEXT:  ret <2 x float> [[SQUARE]]
 ;
   %r = call <2 x float> @llvm.pow.v2f32(<2 x float> %x, <2 x float> <float 2.0, float 2.0>)
   ret <2 x float> %r
@@ -373,10 +358,8 @@
 
 define <2 x double> @pow2_double_strictv(<2 x double> %x) {
 ; CHECK-LABEL: @pow2_double_strictv(
-; ANY-NEXT:    [[SQUARE:%.*]] = fmul <2 x double> [[X:%.*]], [[X]]
-; ANY-NEXT:    ret <2 x double> [[SQUARE]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> [[X:%.*]], <2 x double> <double 2.000000e+00, double 2.000000e+00>)
-; MSVC-NEXT:   ret <2 x double> [[POW]]
+; CHECK-NEXT:  [[SQUARE:%.*]] = fmul <2 x double> [[X:%.*]], [[X]]
+; CHECK-NEXT:  ret <2 x double> [[SQUARE]]
 ;
   %r = call <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double 2.0, double 2.0>)
   ret <2 x double> %r
@@ -422,10 +405,8 @@
 
 define <2 x float> @pow_neg1_strictv(<2 x float> %x) {
 ; CHECK-LABEL: @pow_neg1_strictv(
-; ANY-NEXT:    [[RECIPROCAL:%.*]] = fdiv <2 x float> <float 1.000000e+00, float 1.000000e+00>, [[X:%.*]]
-; ANY-NEXT:    ret <2 x float> [[RECIPROCAL]]
-; MSVC-NEXT:   [[POW:%.*]] = call <2 x float> @llvm.pow.v2f32(<2 x float> [[X:%.*]], <2 x float> <float -1.000000e+00, float -1.000000e+00>)
-; MSVC-NEXT:   ret <2 x float> [[POW]]
+; CHECK-NEXT:  [[RECIPROCAL:%.*]] = fdiv <2 x float> <float 1.000000e+00, float 1.000000e+00>, [[X:%.*]]
+; CHECK-NEXT:  ret <2 x float> [[RECIPROCAL]]
 ;
   %r = call <2 x float> @llvm.pow.v2f32(<2 x float> %x, <2 x float> <float -1.0, float -1.0>)
   ret <2 x float> %r
@@ -442,10 +423,8 @@
 
 define <2 x double> @pow_neg1_double_fastv(<2 x double> %x) {
 ; CHECK-LABEL: @pow_neg1_double_fastv(
-; ANY-NEXT:    [[RECIPROCAL:%.*]] = fdiv fast <2 x double> <double 1.000000e+00, double 1.000000e+00>, [[X:%.*]]
-; ANY-NEXT:    ret <2 x double> [[RECIPROCAL]]
-; MSVC-NEXT:   [[POW:%.*]] = call fast <2 x double> @llvm.pow.v2f64(<2 x double> [[X:%.*]], <2 x double> <double -1.000000e+00, double -1.000000e+00>)
-; MSVC-NEXT:   ret <2 x double> [[POW]]
+; CHECK-NEXT:  [[RECIPROCAL:%.*]] = fdiv fast <2 x double> <double 1.000000e+00, double 1.000000e+00>, [[X:%.*]]
+; CHECK-NEXT:  ret <2 x double> [[RECIPROCAL]]
 ;
   %r = call fast <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double -1.0, double -1.0>)
   ret <2 x double> %r
Index: test/Transforms/InstCombine/pow-3.ll
===================================================================
--- test/Transforms/InstCombine/pow-3.ll
+++ test/Transforms/InstCombine/pow-3.ll
@@ -8,8 +8,7 @@
 
 define double @test_simplify_unavailable1(double %x) {
 ; CHECK-LABEL: @test_simplify_unavailable1(
-; CHECK-NEXT:    [[RETVAL:%.*]] = call double @llvm.pow.f64(double [[X:%.*]], double 5.000000e-01)
-; CHECK-NEXT:    ret double [[RETVAL]]
+; CHECK-NEXT:    = call double @llvm.sqrt.f64
 ;
   %retval = call double @llvm.pow.f64(double %x, double 0.5)
   ret double %retval
Index: test/Transforms/InstCombine/pow-amdgcn.ll
===================================================================
--- /dev/null
+++ test/Transforms/InstCombine/pow-amdgcn.ll
@@ -0,0 +1,55 @@
+; RUN: opt < %s -mtriple=amdgcn-- -targetlibinfo -instcombine -S | FileCheck %s
+
+; Check that a transform of llvm.pow to multiplies or divides happens for amdgcn (for which
+; TLI says no lib functions).
+
+define float @pow_of_1(float %x) {
+; CHECK-LABEL: @pow_of_1(
+; CHECK-NEXT: ret float
+;
+  %pow = call float @llvm.pow.f32(float 1.0, float %x)
+  ret float %pow
+}
+
+define float @pow_minus_1(float %x) {
+; CHECK-LABEL: @pow_minus_1(
+; CHECK: = fdiv float
+;
+  %pow = call float @llvm.pow.f32(float %x, float -1.0)
+  ret float %pow
+}
+
+define float @pow_0(float %x) {
+; CHECK-LABEL: @pow_0(
+; CHECK-NEXT: ret float
+;
+  %pow = call float @llvm.pow.f32(float %x, float 0.0)
+  ret float %pow
+}
+
+define float @pow_1(float %x) {
+; CHECK-LABEL: @pow_1(
+; CHECK-NEXT: ret float
+;
+  %pow = call float @llvm.pow.f32(float %x, float 1.0)
+  ret float %pow
+}
+
+define float @pow_half(float %x) {
+; CHECK-LABEL: @pow_half(
+; CHECK: @llvm.sqrt
+;
+  %pow = call float @llvm.pow.f32(float %x, float 0.5)
+  ret float %pow
+}
+
+define float @pow_2(float %x) {
+; CHECK-LABEL: @pow_2(
+; CHECK: = fmul float
+;
+  %pow = call float @llvm.pow.f32(float %x, float 2.0)
+  ret float %pow
+}
+
+declare float @llvm.pow.f32(float, float)
+