Work around x86-64 calling convention bug

Microsoft's x86-64 calling convention ABI requires registers XMM6-15 to
be preserved by the callee:
https://docs.microsoft.com/en-us/cpp/build/x64-calling-convention?view=vs-2017#calling-convention-defaults
Currently only the System V calling convention's behavior is supported,
which does not have any callee-saved XMM registers.

Fixing this properly is non-trivial and this bug is blocking other
projects, so a temporary workaround is to limit Subzero to use only
scratch registers XMM0-XMM5.

Bug chromium:931926
Bug swiftshader:22

Change-Id: If3fde2295fc65fc52042124afe7dfc46873cce3f
Reviewed-on: https://swiftshader-review.googlesource.com/c/25568
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>

src/Common/Version.h

diff --git a/src/Common/Version.h b/src/Common/Version.h
index 78c74b2..423fcf1 100644
--- a/src/Common/Version.h
+++ b/src/Common/Version.h
@@ -15,7 +15,7 @@
 #define MAJOR_VERSION 4
 #define MINOR_VERSION 1
 #define BUILD_VERSION 0
-#define BUILD_REVISION 5
+#define BUILD_REVISION 6
 
 #define STRINGIFY(x) #x
 #define MACRO_STRINGIFY(x) STRINGIFY(x)

third_party/subzero/src/IceInstX8664.def

diff --git a/third_party/subzero/src/IceInstX8664.def b/third_party/subzero/src/IceInstX8664.def
index 57038d6..3d455a6 100644
--- a/third_party/subzero/src/IceInstX8664.def
+++ b/third_party/subzero/src/IceInstX8664.def
@@ -239,25 +239,25 @@
     NO_ALIASES())                                                              \
   X(Reg_xmm5,   5, "xmm5",  Reg_xmm5,  1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm6,   6, "xmm6",  Reg_xmm6,  1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm6,   6, "xmm6",  Reg_xmm6,  0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm7,   7, "xmm7",  Reg_xmm7,  1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm7,   7, "xmm7",  Reg_xmm7,  0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm8,   8, "xmm8",  Reg_xmm8,  1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm8,   8, "xmm8",  Reg_xmm8,  0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm9,   9, "xmm9",  Reg_xmm9,  1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm9,   9, "xmm9",  Reg_xmm9,  0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm10, 10, "xmm10", Reg_xmm10, 1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm10, 10, "xmm10", Reg_xmm10, 0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm11, 11, "xmm11", Reg_xmm11, 1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm11, 11, "xmm11", Reg_xmm11, 0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm12, 12, "xmm12", Reg_xmm12, 1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm12, 12, "xmm12", Reg_xmm12, 0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm13, 13, "xmm13", Reg_xmm13, 1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm13, 13, "xmm13", Reg_xmm13, 0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm14, 14, "xmm14", Reg_xmm14, 1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm14, 14, "xmm14", Reg_xmm14, 0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
-  X(Reg_xmm15, 15, "xmm15", Reg_xmm15, 1,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
+  X(Reg_xmm15, 15, "xmm15", Reg_xmm15, 0,0,0,0,0, 0,0,0,0,0, 1, 0,0,0,0,0,     \
     NO_ALIASES())                                                              \
   /* End of xmm register set */
 //#define X(val, encode, name, base, scratch, preserved, stackptr, frameptr,