Commit Graph

675 Commits

Author SHA1 Message Date
Chris Lattner
e7a31c98db Codegen floating point stores of constants into integer instructions. This
allows us to compile:

store float 10.0, float* %P

into:
        mov DWORD PTR [%EAX], 1092616192

instead of:

.CPItest_0:                                     # float 0x4024000000000000
.long   1092616192      # float 10
...
        fld DWORD PTR [.CPItest_0]
        fstp DWORD PTR [%EAX]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13409 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-07 21:18:15 +00:00
Chris Lattner
260195d2b1 Make comparisons against the null pointer as efficient as integer comparisons
against zero.  In particular, don't emit:

        mov %ESI, 0
        cmp %ECX, %ESI

instead, emit:

       test %ECX, %ECX


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13407 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-07 19:55:55 +00:00
Chris Lattner
bbc130d110 Remove unneeded check
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13355 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-04 19:35:11 +00:00
Chris Lattner
c8af02c403 Improve signed division by power of 2 *dramatically* from this:
div:
        mov %EDX, DWORD PTR [%ESP + 4]
        mov %ECX, 64
        mov %EAX, %EDX
        sar %EDX, 31
        idiv %ECX
        ret

to this:

div:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %ECX, %EAX
        sar %ECX, 5
        shr %ECX, 26
        mov %EDX, %EAX
        add %EDX, %ECX
        sar %EAX, 6
        ret

Note that the intel compiler is currently making this:

div:
        movl      4(%esp), %edx                                 #3.5
        movl      %edx, %eax                                    #4.14
        sarl      $5, %eax                                      #4.14
        shrl      $26, %eax                                     #4.14
        addl      %edx, %eax                                    #4.14
        sarl      $6, %eax                                      #4.14
        ret                                                     #4.14

Which has one less register->register copy.  (hint hint alkis :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13354 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-04 19:33:58 +00:00
Chris Lattner
9eb9b8ecb9 Improve code generated for integer multiplications by 2,3,5,9
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13342 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-04 15:47:14 +00:00
Chris Lattner
77993632a1 Remove unused #include
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13304 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-01 21:29:16 +00:00
Chris Lattner
2268684f6f Iterate over the Machine CFG that Brian added instead of the LLVM CFG.
Look at all of the pretty minuses. :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13303 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-01 21:27:53 +00:00
Brian Gaeke
1afe7736ff Make RequiresFPRegKill() take a MachineBasicBlock arg.
In InsertFPRegKills(), just check the MachineBasicBlock for successors
instead of its corresponding BasicBlock.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13213 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-28 04:45:55 +00:00
Brian Gaeke
235aa5eba7 In InsertFPRegKills(), use the machine-CFG itself rather than the
LLVM CFG when trying to find the successors of BB.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13212 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-28 04:34:16 +00:00
Brian Gaeke
ea9ca67304 Update the machine-CFG edges whenever we see a branch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13211 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-28 04:19:37 +00:00
Brian Gaeke
b61fc83ecb Use emitWordAt() to emit forward-branch fixups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13120 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-23 17:11:16 +00:00
John Criswell
53b54be5fc Remove code to adjust the iterator for llvm.readio and llvm.writeio.
The iterator is pointing at the next instruction which should not disappear
when doing the load/store replacement.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12954 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-14 21:27:56 +00:00
Chris Lattner
098e945fbd This is the real fix for Codegen/X86/2004-04-13-FPCMOV-Crash.llx which works
even when the "optimization" I added before is turned off.  It generates this
extremely pointless code:

test:
        fld QWORD PTR [%ESP + 4]
        mov %AL, 0
        test %AL, %AL
        fcmove %ST(0), %ST(0)
        ret

Good thing the optimizer will have removed this before code generation
anyway.  :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12939 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-14 02:42:32 +00:00
John Criswell
e5a4c15da6 Added support for the llvm.readio and llvm.writeio intrinsics.
On x86, memory operations occur in-order, so these are just lowered into
volatile loads and stores.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12936 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 22:13:14 +00:00
Chris Lattner
82c5a9990f Implement a small optimization, which papers over the problem in
X86/2004-04-13-FPCMOV-Crash.llx

A more robust fix is to follow.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12935 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 21:56:09 +00:00
Chris Lattner
87e18deabc Emit the immediate form of in/out when possible.
Fix several bugs in the intrinsics:
  1. Make sure to copy the input registers before the instructions that use them
  2. Make sure to copy the value returned by 'in' out of EAX into the register
     it is supposed to be in.

This fixes assertions when using in/out and linear scan.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12896 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 17:20:37 +00:00
Chris Lattner
440bbc257e Add immediate forms of in/out. Use let to shorten lines
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12895 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 17:19:31 +00:00
Chris Lattner
e47f4ff9f6 Add support for new instruction type
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12894 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 17:18:51 +00:00
Chris Lattner
266538350a Add support for the printImplicitDefsBefore flag
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12893 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 17:18:39 +00:00
Chris Lattner
133dbb1285 Fix issues that the local allocator has dealing with instructions that implicitly use ST(0)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12855 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 03:02:48 +00:00
Chris Lattner
284b496aae No really, fix printing for LLC. I gotta get a way for CVS to whine at me if
I have unsaved emacs buffers, geeze...


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12854 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 01:52:04 +00:00
Chris Lattner
2fc83a5ba6 Correct printing for LLC and the encoding for the JIT
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12853 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 01:50:04 +00:00
Chris Lattner
8d2822e7f1 Use the fucomi[p] instructions to perform floating point comparisons instead
of the fucom[p][p] instructions.  This allows us to code generate this function

bool %test(double %X, double %Y) {
        %C = setlt double %Y, %X
        ret bool %C
}

... into:

test:
        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [%ESP + 12]
        fucomip %ST(1)
        fstp %ST(0)
        setb %AL
        movsx %EAX, %AL
        ret

where before we generated:

test:
        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [%ESP + 12]
        fucompp
**      fnstsw
**      sahf
        setb %AL
        movsx %EAX, %AL
        ret

The two marked instructions (which are the ones eliminated) are very bad,
because they serialize execution of the processor.  These instructions are
available on the PPRO and later, but since we already use cmov's we aren't
losing any portability.

I retained the old code for the day when we decide we want to support back
to the 386.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12852 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 01:43:36 +00:00
Chris Lattner
c040bca4b9 Add support for the FUCOMIr instruction
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12851 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 01:39:15 +00:00
Chris Lattner
a1b5e160ed Add two new instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12850 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 01:38:55 +00:00
Chris Lattner
9938286325 Fix a bug in my load/cast folding patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12849 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 00:23:04 +00:00
Chris Lattner
13c07feb20 Adjust some comments, fix a bug in my previous patch
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12848 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 00:12:04 +00:00
Chris Lattner
feac3e18aa On X86, casting an integer to floating point requires going through memory.
If the source of the cast is a load, we can just use the source memory location,
without having to create a temporary stack slot entry.

Before we code generated this:

double %int(int* %P) {
        %V = load int* %P
        %V2 = cast int %V to double
        ret double %V2
}

into:

int:
        sub %ESP, 4
        mov %EAX, DWORD PTR [%ESP + 8]
        mov %EAX, DWORD PTR [%EAX]
        mov DWORD PTR [%ESP], %EAX
        fild DWORD PTR [%ESP]
        add %ESP, 4
        ret

Now we produce this:

int:
        mov %EAX, DWORD PTR [%ESP + 4]
        fild DWORD PTR [%EAX]
        ret

... which is nicer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12846 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 23:21:26 +00:00
Chris Lattner
95157f7638 Implement folding of loads into floating point operations. This implements:
test/Regression/CodeGen/X86/fp_load_fold.llx


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12844 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 22:05:45 +00:00
Chris Lattner
6621ed94cc Unify all of the code for floating point +,-,*,/ into one function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12842 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 21:23:56 +00:00
Chris Lattner
8ebf1c35a1 This implements folding of constant operands into floating point operations
for mul and div.

Instead of generating this:

test_divr:
        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [.CPItest_divr_0]
        fdivrp %ST(1)
        ret

We now generate this:

test_divr:
        fld QWORD PTR [%ESP + 4]
        fdivr QWORD PTR [.CPItest_divr_0]
        ret

This code desperately needs refactoring, which will come in the next
patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12841 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 21:09:14 +00:00
Chris Lattner
462fa82270 Restructure the mul/div/rem handling code to follow the pattern the other
instructions use.  This doesn't change any functionality except that long
constant expressions of these operations will now magically start working.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12840 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 20:56:28 +00:00
Chris Lattner
48b0c97e20 Codegen FP adds and subtracts with a constant more efficiently, generating:
fld QWORD PTR [%ESP + 4]
        fadd QWORD PTR [.CPItest_add_0]

instead of:

        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [.CPItest_add_0]
        faddp %ST(1)

I also intend to do this for mul & div, but it appears that I have to
refactor a bit of code before I can do so.

This is tested by: test/Regression/CodeGen/X86/fp_constant_op.llx


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12839 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 20:26:20 +00:00
Chris Lattner
490e86fed5 Add some new instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12838 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 20:24:15 +00:00
Chris Lattner
4cf15e7a3b Relax assertion to make this function work with a broader class of instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12836 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 20:21:06 +00:00
Chris Lattner
427aeb476f Two changes:
1. If an incoming argument is dead, don't load it from the stack
  2. Do not code gen noop copies at all (ie, cast int -> uint), not even to
     a move.  This should reduce register pressure for allocators that are
     unable to coallesce away these copies in some cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12835 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 19:21:59 +00:00
Chris Lattner
85aa7097c2 Silence a spurious warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12815 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 18:32:01 +00:00
John Criswell
6d804f408a Reversed the order of the llvm.writeport() operands so that the value
is listed first and the address is listed second.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12795 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 19:09:14 +00:00
John Criswell
aee0cf3fca Changed assertions to error messages.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12787 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 15:10:15 +00:00
John Criswell
ca6ea0f137 Changes recommended by Chris:
InstSelectSimple.cpp:
  Change the checks for proper I/O port address size into an exit() instead
  of an assertion.  Assertions aren't used in Release builds, and handling
  this error should be graceful (not that this counts as graceful, but it's
  more graceful).

  Modified the generation of the IN/OUT instructions to have 0 arguments.
X86InstrInfo.td:
  Added the OpSize attribute to the 16 bit IN and OUT instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12786 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-08 22:39:13 +00:00
John Criswell
4ffff9e2fa Added the llvm.readport and llvm.writeport intrinsics for x86. These do
I/O port instructions on x86.  The specific code sequence is tailored to
the parameters and return value of the intrinsic call.
Added the ability for implicit defintions to be printed in the Instruction
Printer.
Added the ability for RawFrm instruction to print implict uses and
defintions with correct comma output.  This required adjustment to some
methods so that a leading comma would or would not be printed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12782 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-08 20:31:47 +00:00
Jakub Staszak
8ac0009979 file based off InstSelectSimple.cpp, slowly being replaced by generated code from the really simple X86 instruction selector tablegen backend
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12715 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 19:35:17 +00:00
Jakub Staszak
0a8fd30c1b Tablgen files for really simple instruction selector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12714 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 19:34:00 +00:00
Chris Lattner
7b92de1e7d Fix PR313: [x86] JIT miscompiles unsigned short to floating point
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12711 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 19:29:36 +00:00
Chris Lattner
43ab3a8f45 Fix incorrect encoding of some ADC and SBB instuctions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12710 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 19:20:32 +00:00
Chris Lattner
48c937e5c9 Fix a minor bug in previous checking
Enable folding of long seteq/setne comparisons into branches and select instructions
Implement unfolded long relational comparisons against a constants a bit more efficiently

Folding comparisons changes code that looks like this:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EDX, DWORD PTR [%ESP + 8]
        mov %ECX, %EAX
        or %ECX, %EDX
        sete %CL
        test %CL, %CL
        je .LBB2 # PC rel: F

into code that looks like this:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EDX, DWORD PTR [%ESP + 8]
        mov %ECX, %EAX
        or %ECX, %EDX
        jne .LBB2 # PC rel: F

This speeds up 186.crafty by 6% with llc-ls.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12702 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 17:34:50 +00:00
Chris Lattner
e80e637793 Improve codegen of long == and != comparisons against constants. Before,
comparing a long against zero got us this:

        sub %ESP, 8
        mov DWORD PTR [%ESP + 4], %ESI
        mov DWORD PTR [%ESP], %EDI
        mov %EAX, DWORD PTR [%ESP + 12]
        mov %EDX, DWORD PTR [%ESP + 16]
        mov %ECX, 0
        mov %ESI, 0
        mov %EDI, %EAX
        xor %EDI, %ECX
        mov %ECX, %EDX
        xor %ECX, %ESI
        or %EDI, %ECX
        sete %CL
        test %CL, %CL
        je .LBB2 # PC rel: F

Now it gets us this:

        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EDX, DWORD PTR [%ESP + 8]
        mov %ECX, %EAX
        or %ECX, %EDX
        sete %CL
        test %CL, %CL
        je .LBB2 # PC rel: F


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12696 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 16:02:27 +00:00
Chris Lattner
6ab06d5d19 Handle various other important cases of multiplying a long constant immediate. For
example, multiplying X*(1 + (1LL << 32)) now produces:

test:
        mov %ECX, DWORD PTR [%ESP + 4]
        mov %EDX, DWORD PTR [%ESP + 8]
        mov %EAX, %ECX
        add %EDX, %ECX
        ret

[[[Note to Alkis: why isn't linear scan generating this code??  This might be a
 problem with your intervals being too conservative:

test:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EDX, DWORD PTR [%ESP + 8]
        add %EDX, %EAX
        ret

end note]]]

Whereas GCC produces this:

T:
        sub     %esp, 12
        mov     %edx, DWORD PTR [%esp+16]
        mov     DWORD PTR [%esp+8], %edi
        mov     %ecx, DWORD PTR [%esp+20]
        xor     %edi, %edi
        mov     DWORD PTR [%esp], %ebx
        mov     %ebx, %edi
        mov     %eax, %edx
        mov     DWORD PTR [%esp+4], %esi
        add     %ebx, %edx
        mov     %edi, DWORD PTR [%esp+8]
        lea     %edx, [%ecx+%ebx]
        mov     %esi, DWORD PTR [%esp+4]
        mov     %ebx, DWORD PTR [%esp]
        add     %esp, 12
        ret

I'm not sure example what GCC is smoking here, but it looks like it has just
confused itself with a bunch of stack slots or something.  The intel compiler
is better, but still not good:

T:
        movl      4(%esp), %edx                                 #2.11
        movl      8(%esp), %eax                                 #2.11
        lea       (%eax,%edx), %ecx                             #3.12
        movl      $1, %eax                                      #3.12
        mull      %edx                                          #3.12
        addl      %ecx, %edx                                    #3.12
        ret                                                     #3.12


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12693 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 04:55:43 +00:00
Chris Lattner
028adc422d Efficiently handle a long multiplication by a constant. For this testcase:
long %test(long %X) {
        %Y = mul long %X, 123
        ret long %Y
}

we used to generate:

test:
        sub %ESP, 12
        mov DWORD PTR [%ESP + 8], %ESI
        mov DWORD PTR [%ESP + 4], %EDI
        mov DWORD PTR [%ESP], %EBX
        mov %ECX, DWORD PTR [%ESP + 16]
        mov %ESI, DWORD PTR [%ESP + 20]
        mov %EDI, 123
        mov %EBX, 0
        mov %EAX, %ECX
        mul %EDI
        imul %ESI, %EDI
        add %ESI, %EDX
        imul %ECX, %EBX
        add %ESI, %ECX
        mov %EDX, %ESI
        mov %EBX, DWORD PTR [%ESP]
        mov %EDI, DWORD PTR [%ESP + 4]
        mov %ESI, DWORD PTR [%ESP + 8]
        add %ESP, 12
        ret

Now we emit:
test:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %ECX, DWORD PTR [%ESP + 8]
        mov %EDX, 123
        mul %EDX
        imul %ECX, %ECX, 123
        add %ECX, %EDX
        mov %EDX, %ECX
        ret

Which, incidently, is substantially nicer than what GCC manages:
T:
        sub     %esp, 8
        mov     %eax, 123
        mov     DWORD PTR [%esp], %ebx
        mov     %ebx, DWORD PTR [%esp+16]
        mov     DWORD PTR [%esp+4], %esi
        mov     %esi, DWORD PTR [%esp+12]
        imul    %ecx, %ebx, 123
        mov     %ebx, DWORD PTR [%esp]
        mul     %esi
        mov     %esi, DWORD PTR [%esp+4]
        add     %esp, 8
        lea     %edx, [%ecx+%edx]
        ret


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12692 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 04:29:36 +00:00
Chris Lattner
722070e0ba Improve code generation of long shifts by 32.
On this testcase:

long %test(long %X) {
        %Y = shr long %X, ubyte 32
        ret long %Y
}

instead of:
t:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EAX, DWORD PTR [%ESP + 8]
        sar %EAX, 0
        mov %EDX, 0
        ret


we now emit:
test:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %EAX, DWORD PTR [%ESP + 8]
        mov %EDX, 0
        ret


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12688 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-06 03:42:38 +00:00