diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -2835,8 +2835,17 @@
   if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
     return emitGlobalConstantVector(DL, V, AP);
 
-  // Otherwise, it must be a ConstantExpr.  Lower it to an MCExpr, then emit it
-  // thread the streamer with EmitValue.
+  // Otherwise, it must be a ConstantExpr.
+
+  // First, try to constant fold floating point constant expressions to a FP
+  // constant. Those cannot be lowered to MCExpr.
+  if (CV->getType()->isFloatingPointTy()) {
+    ConstantFP *New = cast<ConstantFP>(ConstantFoldConstant(CV, DL));
+    if (New)
+      return emitGlobalConstantFP(New, AP);
+  }
+
+  // Lower it to an MCExpr, then emit it thread the streamer with EmitValue.
   const MCExpr *ME = AP.lowerConstant(CV);
 
   // Since lowerConstant already folded and got rid of all IR pointer and
diff --git a/llvm/test/CodeGen/AArch64/complex-float-constexpr-global-initializer.ll b/llvm/test/CodeGen/AArch64/complex-float-constexpr-global-initializer.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/complex-float-constexpr-global-initializer.ll
@@ -0,0 +1,78 @@
+; RUN: llc -o - %s | FileCheck %s
+
+target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+target triple = "arm64-apple-ios13.0.0"
+
+; Make sure complex floating point constant expressions are lowered properly.
+
+@g = global [1 x <2 x float>] [<2 x float>
+      <float fneg (float extractelement (<4 x float> bitcast (<1 x i128> <i128 1> to <4 x float>), i32 0)),
+       float fneg (float extractelement (<4 x float> <float 0.0, float 10.5, float 0.0, float 0.0>, i32 1))>]
+
+define [1 x <2 x float>] @load1() {
+; CHECK-LABEL: _load1:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT: ; %bb.0:
+; CHECK-NEXT: Lloh0:
+; CHECK-NEXT:    adrp    x8, _g@PAGE
+; CHECK-NEXT: Lloh1:
+; CHECK-NEXT:    ldr d0, [x8, _g@PAGEOFF]
+; CHECK-NEXT:    ret
+
+  %r = load [1 x <2 x float>], [1 x <2 x float>]* @g
+  ret [1 x <2 x float>] %r
+}
+
+@h = global [1 x <2 x float>] [<2 x float> fadd
+      (<2 x float> bitcast (<1 x i64> <i64 10> to <2 x float>),
+       <2 x float> <float 0.0, float 10.5>)]
+
+define [1 x <2 x float>] @load2() {
+; CHECK-LABEL: _load2:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT: ; %bb.0:
+; CHECK-NEXT: Lloh2:
+; CHECK-NEXT:    adrp    x8, _h@PAGE
+; CHECK-NEXT: Lloh3:
+; CHECK-NEXT:    ldr d0, [x8, _h@PAGEOFF]
+; CHECK-NEXT:    ret
+
+  %r = load [1 x <2 x float>], [1 x <2 x float>]* @h
+  ret [1 x <2 x float>] %r
+}
+
+
+
+define [1 x <2 x float>] @promoted() {
+; CHECK-LABEL: _promoted:
+; CHECK-NEXT:     .cfi_startproc
+; CHECK-NEXT: ; %bb.0:
+; CHECK-NEXT: Lloh4:
+; CHECK-NEXT:     adrp    x8, __PromotedConst@PAGE
+; CHECK-NEXT: Lloh5:
+; CHECK-NEXT:     ldr d0, [x8, __PromotedConst@PAGEOFF]
+; CHECK-NEXT:     ret
+
+  ret [1 x <2 x float>] [<2 x float>
+      <float fneg (float extractelement (<4 x float> bitcast (<1 x i128> <i128 84405977232342107929391748327801880576> to <4 x float>), i32 0)),
+       float fneg (float extractelement (<4 x float> bitcast (<1 x i128> <i128 0> to <4 x float>), i32 1))>]
+}
+
+; CHECK-LABEL:     .section    __DATA,__data
+; CHECK-NEXT:      .globl  _g                      ; @g
+; CHECK-NEXT:      .p2align    3
+; CHECK-NEXT:  _g:
+; CHECK-NEXT:      .long   0x80000001              ; float -1.40129846E-45
+; CHECK-NEXT:      .long   0xc1280000              ; float -10.5
+
+; CHECK:           .globl  _h                      ; @h
+; CHECK-NEXT:      .p2align    3
+; CHECK-NEXT:  _h:
+; CHECK-NEXT:      .long   0x0000000a              ; float 1.40129846E-44
+; CHECK-NEXT:      .long   0x41280000              ; float 10.5
+
+; CHECK-LABEL:    .section    __TEXT,__const
+; CHECK-NEXT:     .p2align    3               ; @_PromotedConst
+; CHECK-NEXT: __PromotedConst:
+; CHECK-NEXT:     .long   0xe4c00000              ; float -2.83341989E+22
+; CHECK-NEXT:     .long   0x80000000              ; float -0
diff --git a/llvm/test/CodeGen/X86/complex-float-constexpr-global-initializer.ll b/llvm/test/CodeGen/X86/complex-float-constexpr-global-initializer.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/X86/complex-float-constexpr-global-initializer.ll
@@ -0,0 +1,53 @@
+; RUN: llc -o - %s | FileCheck %s
+
+target triple = "x86_64-apple-darwin"
+
+; Make sure complex floating point constant expressions are lowered properly.
+
+@g = global [1 x <2 x float>] [<2 x float>
+      <float fneg (float extractelement (<4 x float> bitcast (<1 x i128> <i128 1> to <4 x float>), i32 0)),
+       float fneg (float extractelement (<4 x float> <float 0.0, float 10.5, float 0.0, float 0.0>, i32 1))>]
+
+define [1 x <2 x float>] @load1() {
+; CHECK-LABEL:    .globl  _load1                   ## -- Begin function load
+; CHECK-NEXT:     .p2align    4, 0x90
+; CHECK-NEXT: _load1:                                  ## @load1
+; CHECK-NEXT:     .cfi_startproc
+; CHECK-NEXT: ## %bb.0:
+; CHECK-NEXT:     movsd   _g(%rip), %xmm0         ## xmm0 = mem[0],zero
+; CHECK-NEXT:     retq
+
+  %r = load [1 x <2 x float>], [1 x <2 x float>]* @g
+  ret [1 x <2 x float>] %r
+}
+
+@h = global [1 x <2 x float>] [<2 x float> fadd
+      (<2 x float> bitcast (<1 x i64> <i64 10> to <2 x float>),
+       <2 x float> <float 0.0, float 10.5>)]
+
+define [1 x <2 x float>] @load2() {
+; CHECK-LABEL:    .globl  _load2                   ## -- Begin function load2
+; CHECK-NEXT:     .p2align    4, 0x90
+; CHECK-NEXT: _load2:                                  ## @load2
+; CHECK-NEXT:     .cfi_startproc
+; CHECK-NEXT: ## %bb.0:
+; CHECK-NEXT:     movsd   _h(%rip), %xmm0         ## xmm0 = mem[0],zero
+; CHECK-NEXT:     retq
+
+  %r = load [1 x <2 x float>], [1 x <2 x float>]* @h
+  ret [1 x <2 x float>] %r
+}
+
+
+; CHECK-LABEL:     .section    __DATA,__data
+; CHECK-NEXT:     .globl  _g                      ## @g
+; CHECK-NEXT:     .p2align    3
+; CHECK-NEXT: _g:
+; CHECK-NEXT:     .long   0x80000001              ## float -1.40129846E-45
+; CHECK-NEXT:     .long   0xc1280000              ## float -10.5
+
+; CHECK:           .globl  _h                     ## @h
+; CHECK-NEXT:      .p2align    3
+; CHECK-NEXT:  _h:
+; CHECK-NEXT:      .long   0x0000000a              ## float 1.40129846E-44
+; CHECK-NEXT:      .long   0x41280000              ## float 10.5