[X86] Don't use PS prefix on LDMXCSR/STMXCSR.

Near as I can tell prefixes are ignored on these instructions except for a comment in the Intel docs about 0xf3. Binutils disassembler seems to ignore prefixes on these instructions. Our disassembler still doesn't distinguish PS and "no prefix" well enough for this to make a functional change, but it helps with experiments I'm doing on a potential new disassembler table builder.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224496 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86InstrSSE.td b/lib/Target/X86/X86InstrSSE.td
index 0474bb99b915cf72d04c409f32a215efce2ad9c9..3093f0bc044ccb50098aaf207f3d6a65053ecfaf 100644 (file)
--- a/lib/Target/X86/X86InstrSSE.td
+++ b/lib/Target/X86/X86InstrSSE.td
@@ -4029,12 +4029,14 @@ def VSTMXCSR : VPSI<0xAE, MRM3m, (outs), (ins i32mem:$dst),
                   "stmxcsr\t$dst", [(int_x86_sse_stmxcsr addr:$dst)],
                   IIC_SSE_STMXCSR>, VEX, Sched<[WriteStore]>;
 
-def LDMXCSR : PSI<0xAE, MRM2m, (outs), (ins i32mem:$src),
-                  "ldmxcsr\t$src", [(int_x86_sse_ldmxcsr addr:$src)],
-                  IIC_SSE_LDMXCSR>, Sched<[WriteLoad]>;
-def STMXCSR : PSI<0xAE, MRM3m, (outs), (ins i32mem:$dst),
-                  "stmxcsr\t$dst", [(int_x86_sse_stmxcsr addr:$dst)],
-                  IIC_SSE_STMXCSR>, Sched<[WriteStore]>;
+let Predicates = [UseSSE1] in {
+def LDMXCSR : I<0xAE, MRM2m, (outs), (ins i32mem:$src),
+                "ldmxcsr\t$src", [(int_x86_sse_ldmxcsr addr:$src)],
+                IIC_SSE_LDMXCSR>, TB, Sched<[WriteLoad]>;
+def STMXCSR : I<0xAE, MRM3m, (outs), (ins i32mem:$dst),
+                "stmxcsr\t$dst", [(int_x86_sse_stmxcsr addr:$dst)],
+                IIC_SSE_STMXCSR>, TB, Sched<[WriteStore]>;
+}
 
 //===---------------------------------------------------------------------===//
 // SSE2 - Move Aligned/Unaligned Packed Integer Instructions