Subzero. Misc fixes.

Makefile.standalone

@@ -221,8 +221,12 @@ SB_OBJS=$(patsubst %.cpp, $(SB_OBJDIR)/%.o, $(SRCS))
 UNITTEST_SRCS = \
 	BitcodeMunge.cpp \
 	IceELFSectionTest.cpp \
-	IceParseInstsTest.cpp \
-        AssemblerX8632/LowLevel.cpp \
+	IceParseInstsTest.cpp
+
+# The X86 assembler tests take too long to compile. Given how infrequently the
+# assembler will change, we disable them.
+ifdef CHECK_X86_ASM
+  UNITTEST_SRCS += AssemblerX8632/LowLevel.cpp \
         AssemblerX8632/DataMov.cpp \
         AssemblerX8632/Locked.cpp \
         AssemblerX8632/GPRArith.cpp \
@@ -237,7 +241,7 @@ UNITTEST_SRCS = \
         AssemblerX8664/XmmArith.cpp \
         AssemblerX8664/ControlFlow.cpp \
         AssemblerX8664/Other.cpp
-
+endif
 
 UNITTEST_OBJS = $(patsubst %.cpp, $(OBJDIR)/unittest/%.o, $(UNITTEST_SRCS))
 UNITTEST_LIB_OBJS = $(filter-out $(OBJDIR)/main.o,$(OBJS))

src/IceTargetLoweringX86BaseImpl.h

@@ -1939,8 +1939,7 @@ void TargetX86Base<Machine>::lowerArithmetic(const InstArithmetic *Inst) {
       Context.insert(InstFakeDef::create(Func, T_eax));
       _xor(T_eax, T_eax);
       _mov(T, Src0, Traits::RegisterSet::Reg_eax);
-      Variable *T_al = makeReg(IceType_i8, Traits::RegisterSet::Reg_eax);
-      _div(T_al, Src1, T);
+      _div(T, Src1, T);
       // shr $8, %eax shifts ah (i.e., the 8 bit remainder) into al. We don't
       // mov %ah, %al because it would make x86-64 codegen more complicated. If
       // this ever becomes a problem we can introduce a pseudo rem instruction
@@ -1948,7 +1947,7 @@ void TargetX86Base<Machine>::lowerArithmetic(const InstArithmetic *Inst) {
       // %ah to %al.)
       static constexpr uint8_t AlSizeInBits = 8;
       _shr(T_eax, Ctx->getConstantInt8(AlSizeInBits));
-      _mov(Dest, T_al);
+      _mov(Dest, T);
       Context.insert(InstFakeUse::create(Func, T_eax));
     } else {
       Constant *Zero = Ctx->getConstantZero(IceType_i32);