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diff --git a/UefiCpuPkg/Library/BaseUefiCpuLib/Ia32/InitializeFpu.S b/UefiCpuPkg/Library/BaseUefiCpuLib/Ia32/InitializeFpu.S
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index 0000000000..c4a2f6fb83
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+++ b/UefiCpuPkg/Library/BaseUefiCpuLib/Ia32/InitializeFpu.S
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+#------------------------------------------------------------------------------
+#*
+#* Copyright 2009, Intel Corporation
+#* All rights reserved. This program and the accompanying materials
+#* are licensed and made available under the terms and conditions of the BSD License
+#* which accompanies this distribution. The full text of the license may be found at
+#* http://opensource.org/licenses/bsd-license.php
+#*
+#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#*
+#*
+#------------------------------------------------------------------------------
+
+
+
+#
+# Float control word initial value:
+# all exceptions masked, double-precision, round-to-nearest
+#
+ASM_PFX(mFpuControlWord): .word 0x027F
+#
+# Multimedia-extensions control word:
+# all exceptions masked, round-to-nearest, flush to zero for masked underflow
+#
+ASM_PFX(mMmxControlWord): .long 0x01F80
+
+#
+# Initializes floating point units for requirement of UEFI specification.
+#
+# This function initializes floating-point control word to 0x027F (all exceptions
+# masked,double-precision, round-to-nearest) and multimedia-extensions control word
+# (if supported) to 0x1F80 (all exceptions masked, round-to-nearest, flush to zero
+# for masked underflow).
+#
+ASM_GLOBAL ASM_PFX(InitializeFloatingPointUnits)
+ASM_PFX(InitializeFloatingPointUnits):
+ #
+ # Initialize floating point units
+ #
+ finit
+ fldcw ASM_PFX(mFpuControlWord)
+
+ #
+ # Use CpuId instructuion (CPUID.01H:EDX.SSE[bit 25] = 1) to test
+ # whether the processor supports SSE instruction.
+ #
+ movl $1, %eax
+ cpuid
+ btl $25, %edx
+ jnc Done
+
+ #
+ # Set OSFXSR bit 9 in CR4
+ #
+ movl %cr4, %eax
+ or $200, %eax
+ movl %eax, %cr4
+
+ #
+ # The processor should support SSE instruction and we can use
+ # ldmxcsr instruction
+ #
+ ldmxcsr ASM_PFX(mMmxControlWord)
+
+Done:
+ ret
+
+#END
+