Index: clang/lib/Frontend/CompilerInvocation.cpp
===================================================================
--- clang/lib/Frontend/CompilerInvocation.cpp
+++ clang/lib/Frontend/CompilerInvocation.cpp
@@ -2437,6 +2437,13 @@
   if (Arch == llvm::Triple::spir || Arch == llvm::Triple::spir64) {
     Res.getDiagnosticOpts().Warnings.push_back("spir-compat");
   }
+
+  // If there will ever be e.g. "LangOpts.C", replace "LangOpts.C11 || LangOpts.C99" with "LangOpts.C" on the next line.
+  if (    (LangOpts.C11 || LangOpts.C99 || LangOpts.CPlusPlus)                      // ...
+  /*...*/ && ( CodeGenOptions::FPC_On == Res.getCodeGenOpts().getFPContractMode() ) // ... // just being careful
+  /*...*/ && ! LangOpts.CUDA)
+    LangOpts.DefaultFPContract = 1;
+
   return Success;
 }
 
Index: clang/test/CodeGen/aarch64-neon-fma.c
===================================================================
--- clang/test/CodeGen/aarch64-neon-fma.c
+++ clang/test/CodeGen/aarch64-neon-fma.c
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -S -emit-llvm -o - %s | opt -S -mem2reg | FileCheck %s
+// RUN: %clang_cc1 -triple arm64-none-linux-gnu -target-feature +neon -ffp-contract=off -S -emit-llvm -o - %s | opt -S -mem2reg | FileCheck %s
 
 // Test new aarch64 intrinsics and types
 
Index: clang/test/CodeGen/fp-contract-pragma.cpp
===================================================================
--- clang/test/CodeGen/fp-contract-pragma.cpp
+++ clang/test/CodeGen/fp-contract-pragma.cpp
@@ -13,6 +13,7 @@
 // CHECK: _Z13fp_contract_2fff
 // CHECK: %[[M:.+]] = fmul float %a, %b
 // CHECK-NEXT: fadd float %[[M]], %c
+  #pragma STDC FP_CONTRACT OFF
   {
     #pragma STDC FP_CONTRACT ON
   }
Index: clang/test/CodeGen/fp-contract-pragma___on-by-default___-O0___aarch64-backend.c
===================================================================
--- /dev/null
+++ clang/test/CodeGen/fp-contract-pragma___on-by-default___-O0___aarch64-backend.c
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -triple aarch64 -O0 -S -o - %s | FileCheck %s
+// REQUIRES: aarch64-registered-target
+
+// CHECK-LABEL: fmadd_double:
+// CHECK: fmadd d0, d{{[0-7]}}, d{{[0-7]}}, d{{[0-7]}}
+double fmadd_double(double a, double b, double c) {
+  return a*b+c;
+}
+
+// CHECK-LABEL: fmadd_single:
+// CHECK: fmadd s0, s{{[0-7]}}, s{{[0-7]}}, s{{[0-7]}}
+float  fmadd_single(float  a, float  b, float  c) {
+  return a*b+c;
+}
+
Index: clang/test/CodeGen/fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h
===================================================================
--- /dev/null
+++ clang/test/CodeGen/fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h
@@ -0,0 +1,14 @@
+// CHECK-LABEL: fmadd_double:
+// CHECK: fmadd d0, d{{[0-7]}}, d{{[0-7]}}, d{{[0-7]}}
+// CHECK-NEXT: ret
+double fmadd_double(double a, double b, double c) {
+  return a*b+c;
+}
+
+// CHECK-LABEL: fmadd_single:
+// CHECK: fmadd s0, s{{[0-7]}}, s{{[0-7]}}, s{{[0-7]}}
+// CHECK-NEXT: ret
+float  fmadd_single(float  a, float  b, float  c) {
+  return a*b+c;
+}
+
Index: clang/test/CodeGen/fp-contract-pragma___on-by-default___-O1___aarch64-backend.c
===================================================================
--- /dev/null
+++ clang/test/CodeGen/fp-contract-pragma___on-by-default___-O1___aarch64-backend.c
@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 -triple aarch64 -O1 -S -o - %s | FileCheck %S/fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h
+// REQUIRES: aarch64-registered-target
+
+#include "fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h"
Index: clang/test/CodeGen/fp-contract-pragma___on-by-default___-O2___aarch64-backend.c
===================================================================
--- /dev/null
+++ clang/test/CodeGen/fp-contract-pragma___on-by-default___-O2___aarch64-backend.c
@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 -triple aarch64 -O2 -S -o - %s | FileCheck %S/fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h
+// REQUIRES: aarch64-registered-target
+
+#include "fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h"
Index: clang/test/CodeGen/fp-contract-pragma___on-by-default___-O3___aarch64-backend.c
===================================================================
--- /dev/null
+++ clang/test/CodeGen/fp-contract-pragma___on-by-default___-O3___aarch64-backend.c
@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 -triple aarch64 -O3 -S -o - %s | FileCheck %S/fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h
+// REQUIRES: aarch64-registered-target
+
+#include "fp-contract-pragma___on-by-default___-O1...3___aarch64-backend.h"