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Compiler Compare
Volume Number:5
Issue Number:8
Column Tag:Jörg's Folder

Compiler Comparison

By Jörg Langowski, MacTutor Editorial Board

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Code optimization

You will have noticed the change in the column’s title: a recent reader survey has shown that Forth and Basic are the two languages that our readers would most like to see less of in MacTutor. That’s a shame, but we’re responsive (at least we try)

So, from now on my monthly column will have a wider scope. As you might have seen, I have very often used Forth as a vehicle to explain general concepts of Macintosh programming. Since many subscribers don’t seem to be happy with Forth - in fact, people often have asked about things that had been explained in a Forth column, but they just hadn’t read. The column about the Notification Manager in V5#6 is a good example: at the bottom of page 42, one of the ‘ideas to be written’ was explained as: “ An example that places a Notification Manager request in low System memory, and starts a Timer routine ”; this is just the example that was in the Forth Forum that covered the Notification Manager. Anyway, I’ll try to use other vehicles to convey the message from now on. Such as assembly, or maybe even C. Mach2 Forth still is a very good assembly-language development system because of its interactivity. Of course, you cannot create complicated macros, or structures, and have to resort to Forth code for those purposes. I’ll still inform you about interesting things I come across on the Forth scene, but this won’t be an exclusive Forth column anymore. Emphasis will be on two things: basic system-level things such as drivers, trap patches, INITs, network, new managers as they come up; and - on the other side of the spectrum - object-oriented programming in C++.

Apple will ‘Real Soon Now’ release a C++ under MPW, and we’ll hopefully have a pre-release by the time you read this. C++ is a very interesting language, much more than a simple extension of C; reading Stroustrup’s book I got this feeling of ‘yes, that’s how one should have done it in the first place’ that I had 15 years ago when all I knew was Algol 60, and came across the description of Algol 68. Sadly enough, Algol 68 never really caught on; hopefully, C++ will. The C++ column will start with the next issue; including program examples if we get the pre-release soon enough, just ‘dry swimming’ if not.

This month, we’ll talk once more about one of my favorite subjects, number crunching, speed (or the lack of it), and intelligence in compilers (or the lack of it).

A matrix multiplication routine

Since I am doing more and more everyday computation (mostly Fortran) on the MacII, I’m obviously interested in a good optimizing compiler. Now, a standard trick that every decent compiler should have in its repertoire is the elimination of constant expressions from loops, or assignment of array elements that are not dependent on the loop index to intermediate variables.

Imagine my surprise when I found out that (in Language Systems Fortran 1.2.1) I could speed up a loop that looked like this:

 do k=1,n3
 do i=1,n1
 c(i,k) = 0x0
 do j=1,n2
 c(i,k) = c(i,k)+a(i,j)*b(j,k)
 end do
 end do
 end do

by simply writing:

 do k=1,n3
 do i=1,n1
 sum = 0x0
 do j=1,n2
 sum = sum+a(i,j)*b(j,k)
 end do
 c(i,k) = sum
 end do
 end do

Now, in undergraduate programming classes, years ago, we were actually taught to look for constant arithmetical or index expressions in loops and put them outside if possible. Today, almost everybody assumes that the compiler is smart enough to take care of that; incorrectly, as you see. To see how good the compilers available under MPW can do, I wrote a Fortran program (listing 1) that calls several versions of this matrix multiplication loop, written in Fortran (Lang. Sys. 1.2.1), Pascal (Apple 3.0 beta), and C (Apple 3.0 beta). Surprise: none of the compilers was good enough to move the indexing outside of the loop. The following table gives the results (Mac IIx):

Pascal, hand-optimized: 2.7667 seconds

C, register variables, hand-opt.: 3.4667 seconds

Pascal: 4.0333 seconds

Fortran, const. dimensions, opt=3: 4.5000 seconds

Fortran, hand-optimized, opt=3: 4.6500 seconds

C: 4.7167 seconds

Fortran, opt=3: 6.5167 seconds

Fortran, opt=0: 6.6167 seconds

A difference of more than a factor of 2 between the slowest Fortran and the fastest Pascal code. Apple Pascal lived up to its good reputation here, but even that could be improved a lot by eliminating the constant index expression.

Surprised, I ran the Fortran benchmark on a Microvax II, and found that even there some speed could be gained by ‘hand-optimizing’ the code:

Fortran, plain: 3.6333 seconds

Fortran, hand-opt.: 3.2833 seconds

Fortran, const. dimensions: 3.1000 seconds

However, the difference between the machine-optimized and the hand-optimized version is not quite as big as for the MPW languages (15% for the VAX vs. 27-30% for MPW). If you compile the VAX code without optimization, you get a bigger difference (23%):

Fortran, plain: 6.2500 seconds

Fortran, hand-opt.: 4.8833 seconds

Fortran, const. dimensions: 4.8000 seconds

Therefore, take-home lesson one: don’t take compiler optimizations for granted.

The machine code behind it

Benchmarks have been run on lots of different machines, using lots of different compilers. I was interested in how the code generated by the MPW compilers actually differed. A job for Nosy, and the results are shown in the last listing. I’ve only printed the innermost loops. Don’t be overwhelmed by the pile of assembly code, just note some important details.

First, for the loop optimization examples discussed here, there seems to be no tradeoff between code length and speed. On the contrary, the fastest code is also the shortest. On the other hand, there are some obvious pieces of code which are clearly redundant. The most blatant example is the Fortran-generated code at the end of the listing, where an index expression is recalculated that was actually in register A1 all the time! 14 extra lines of machine code on each pass through the loop will add up to quite some extra time lost. Another point is that Language System obviously has no great trust in the quality of the 68000/20/30, otherwise how can one explain that they repeat the EXT.L D2 instruction each time it occurs? To make sure it works at least once?

Language Systems Fortran makes other funny assumptions about the machine, for instance it seems to think there are only two floating point registers in the 68881, FP0 and FP7. I have looked at some code which had great potential for optimization by using enough FP registers. Language Systems is, however, known for its responsiveness towards customers, so I hope we won’t have to wait too long until a well-optimized Fortran shows up.

Both Pascal and C like juggling floating point registers. Why generate (like Apple’s C):

FMOVE   FP7,FP1
FADD    FP0,FP1
FMOVE   FP1,FP7

when a simple FADD FP0,FP7 would suffice? Eliminates two floating point instructions per loop. Pascal does

   FADD    FP7,FP0
   FMOVE   FP0,FP7

when a simple inversion of the operands

   FADD FP0,FP7

would give the same result. One floating point instruction per loop eliminated. The timing difference between the Pascal and C routines is partly because of the one extra floating point instruction.

Last remark: I haven’t seen the Absoft MPW 3.0 Fortran yet. If anyone from Absoft is reading this, I’d like an evaluation copy to run the same analysis (since you claim in your ads you have such a great optimizer). If I get enough other languages collected together, we’ll have a follow-up on this article.

Next month

The MacHack is over (thanks, Aimée, Carol, and all the others, for organizing such a good meeting), and I’ll tell you some of my impressions in the next column. Otherwise, we’ll start with an introduction to C++; I hope the compiler will arrive here in time.

Listing 1: Matrix multiplication benchmark

!!S Main
 program matrix
c
c Main program in Language Systems Fortran
c
c Some line breaks in the Fortran program are due to 
c editing.
c
 implicit none
 
 integer i,j,ticks1,ticks2
 extended a(50,50), b(50,50), c(50,50)
 extended time1,time2
 
 integer ticks
 
 type *,’Matrix multiplication benchmark’
 type *,’------------------------------’
 type *
 type *,’This program compares the number crunching power’
 type *,’of some of the popular MPW compilers.’
 type *,’Written under MPW 3.0 by J. Langowski / MacTutor 1989'
 type *
 type *,’Setting up 50x50 matrices...’

 ticks1 = ticks()
 
 do i=1,50
 do j=1,50
 a(i,j) = (i-1) + j-1
 b(j,i) = a(i,j)
 end do
 end do
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for setting up matrices’’)’) time1
 
 ticks1 = ticks()
 call mat_mult_for3(c,50,a,50,b,50,50,50,50)
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using FORTRAN routine, opt=3'’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 ticks1 = ticks()
 call mat_mult_for(c,50,a,50,b,50,50,50,50)
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using FORTRAN routine, opt=0'’)’) time1
 type *,’c(25,25) = ‘,c(25,25)

 ticks1 = ticks()
 call mat_mult_for1(c,50,a,50,b,50,50,50,50)
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using FORTRAN routine, hand-optimized’’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 ticks1 = ticks()
 call mat_mult_for0(c,50,a,50,b,50,50,50,50)
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using FORTRAN routine, constant dimensions’’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 ticks1 = ticks()
 call mat_mul_pas(c,%val(50),a,%val(50),b,%val(50),%val(50),%val(50),%val(50))
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using PASCAL routine’’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 ticks1 = ticks()
 call mat_mul_pas_opt(c,%val(50),a,%val(50),b,%val(50),%val(50),%val(50),%val(50))
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using PASCAL routine, hand-optimized’’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 ticks1 = ticks()
 call mat_mul_c(c,%val(50),a,%val(50),b,%val(50),%val(50),%val(50),%val(50))
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using C routine’’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 ticks1 = ticks()
 call mat_mul_c_opt(c,%val(50),a,%val(50),b,%val(50),%val(50),%val(50),%val(50))
 
 ticks2 = ticks()
 time1 = (ticks2-ticks1)/60.
 type *
 write (6,’(f8.4,’’ seconds for multiplying matrices’’,
     *  ‘’ using C routine, hand-optimized’’)’) time1
 type *,’c(25,25) = ‘,c(25,25)
 
 end

!!S Main
 subroutine mat_mult_for3(c,nc,a,na,b,nb,n1,n2,n3)
c sets c=a.b
c na,nb,nc are first dimensions
c n1 n2 n3 are problem dimensions
c c is n1xn3
c a    n1 n2
c b    n2 n3
 implicit none
 
 integer na,nb,nc,n1,n2,n3
 integer*2 i,j,k
 extended c(nc,n3),a(na,n2),b(nb,n3)
 
 do k=1,n3
 do i=1,n1
 c(i,k) = 0x0
 do j=1,n2
 c(i,k) = c(i,k)+a(i,j)*b(j,k)
 end do
 end do
 end do
 return
 end

!!S Main
 subroutine mat_mult_for1(c,nc,a,na,b,nb,n1,n2,n3)
c
csame as before, invariant matrix element eliminated from loop
c
 implicit none
 
 integer na,nb,nc,n1,n2,n3
 integer*2 i,j,k
 extended c(nc,n3),a(na,n2),b(nb,n3)
 extended sum 
 
 do k=1,n3
 do i=1,n1
 sum = 0x0
 do j=1,n2
 sum = sum+a(i,j)*b(j,k)
 end do
 c(i,k) = sum
 end do
 end do
 return
 end

!!S Main
 subroutine mat_mult_for0(c,nc,a,na,b,nb,n1,n2,n3)
c
csame as before, with constant dimensions
c
 implicit none
 
 integer na,nb,nc,n1,n2,n3
 integer*2 i,j,k
 extended c(50,50),a(50,50),b(50,50)
 extended sum 
 
 do k=1,n3
 do i=1,n1
 sum = 0x0
 do j=1,n2
 sum = sum+a(i,j)*b(j,k)
 end do
 c(i,k) = sum
 end do
 end do
 return
 end

!!S Main
 integer function ticks
 ticks = long(362)
 return
 end
Listing 2 : non-optimized Fortran routine           
!!S Main
 subroutine mat_mult_for(c,nc,a,na,b,nb,n1,n2,n3)
c
cduplicate of mat_mul_for3 for compiling without optimization
c
 implicit none
 
 integer na,nb,nc,n1,n2,n3
 integer*2 i,j,k
 extended c(nc,n3),a(na,n2),b(nb,n3)
 
 do k=1,n3
 do i=1,n1
 c(i,k) = 0x0
 do j=1,n2
 c(i,k) = c(i,k)+a(i,j)*b(j,k)
 end do
 end do
 end do
 return
 end
Listing 3 : Pascal routine

{$S Main}
{$R-}
unit matmul;

interface

type matrix = array [1..50,1..50] of extended;

procedure mat_mul_pas
 (var c : matrix; nc : longint;
  var a : matrix; na : longint;
  var b : matrix; nb : longint;
  n1,n2,n3:longint);

procedure mat_mul_pas_opt
 (var c : matrix; nc : longint;
  var a : matrix; na : longint;
  var b : matrix; nb : longint;
  n1,n2,n3:longint);

implementation

procedure mat_mul_pas;
var
 i,j,k:integer;
begin
 for k:=1 to n3 do
 for i:=1 to n1 do
 begin
 c[i,k] := 0;
 for j:=1 to n2 do
 c[i,k] := c[i,k]+a[i,j]*b[j,k];
 end;
end;

procedure mat_mul_pas_opt;
var
 i,j,k:integer; sum:extended;
begin
 for k:=1 to n3 do
 for i:=1 to n1 do
 begin
 sum := 0;
 for j:=1 to n2 do
 sum := sum+a[i,j]*b[j,k];
 c[i,k] := sum;
 end;
end;

end.
Listing 4 : C routine

pascal void mat_mul_c 
 (extended c[50][], long nc,
  extended a[50][], long na,
  extended b[50][], long nb,
  long n1, long n2, long n3)

{
 int i,j,k;
 
 for ( k=1 ; k <= n3; k++ )
 for ( i=1 ; i <= n1 ; i++ )
 {
 c[i][k] = 0.0;
 for ( j=1 ; j <= n2 ; j++ )
 c[i][k] = c[i][k]+a[i][j]*b[j][k];
 }
}

pascal void mat_mul_c_opt
 (extended c[50][], long nc,
  extended a[50][], long na,
  extended b[50][], long nb,
  long n1, long n2, long n3)

{
 register int i,j,k;
 register extended sum;
 
 for ( k=1 ; k <= n3; k++ )
 for ( i=1 ; i <= n1 ; i++ )
 {
 sum = 0.0;
 for ( j=1 ; j <= n2 ; j++ )
 sum = sum+a[i][j]*b[j][k];
 c[i][k] = sum;
 }
}
Listing 5 : inner loops compared, Nosy-disassembled

pascal, optimized
lan_3 MOVEA.L  param2(A6),A0
 MOVE D6,D0
 MULS #$258,D0
 MOVE D5,D1
 MULS #12,D1
 ADD  D1,D0
 MOVEA.Lparam3(A6),A1
 MOVE D5,D1
 MULS #$258,D1
 MOVE D7,D2
 MULS #12,D2
 ADD  D2,D1
 LEA  -$264(A0),A0
 FMOVE.X0(A0,D0.W),FP0
 LEA  -$264(A1),A0
 FMUL.X 0(A0,D1.W),FP0
 FADD FP7,FP0  ; could use
 FMOVE  FP0,FP7  ; FADD FP0,FP7 here
 ADDQ #1,D5
 BVS.S  lan_5
lan_4 CMP.W van_1(A6),D5
 BLE  lan_3

c, optimized
lar_1 MOVE.LD7,D0
 MOVE.L D0,D1
 MULU #12,D0
 SWAP D1
 MULU #12,D1
 SWAP D1
 CLR  D1
 ADD.L  D1,D0
 ADD.L  D6,D0
 MOVE.L D5,D1
 MOVE.L D1,D2
 MULU #12,D1
 SWAP D2
 MULU #12,D2
 SWAP D2
 CLR  D2
 ADD.L  D2,D1
 ADD.L  D7,D1
 FMOVE.X  0(A3,D0.L),FP0
 FMUL.X 0(A4,D1.L),FP0
 FMOVE  FP7,FP1
 FADD FP0,FP1
 FMOVE  FP1,FP7
 ADDQ.L #1,D7
lar_2 CMP.L D7,D4
 BGE  lar_1

pascal, plain
lam_3 MOVEA.L  param2(A6),A0
 MOVE D6,D0
 MULS #$258,D0
 MOVE D5,D1
 MULS #12,D1
 ADD  D1,D0
 MOVEA.L  param3(A6),A1
 MOVE D5,D1
 MULS #$258,D1
 MOVE D7,D2
 MULS #12,D2
 ADD  D2,D1
 LEA  -$264(A0),A0
 FMOVE.X 0(A0,D0.W),FP0
 LEA  -$264(A1),A0
 FMUL.X 0(A0,D1.W),FP0
 MOVE D6,D0
 MULS #$258,D0
 MOVE D7,D1
 MULS #12,D1
 ADD  D1,D0
 LEA  -$264(A4),A0
 FADD.X 0(A0,D0.W),FP0
 MOVE D6,D0
 MULS #$258,D0
 MOVE D7,D1
 MULS #12,D1
 ADD  D1,D0
 LEA  -$264(A4),A0
 FMOVE.X FP0,0(A0,D0.W)
 ADDQ #1,D5
 BVS.S  lam_5
lam_4 CMP.W vam_1(A6),D5
 BLE  lam_3

c, plain
lao_3 MOVE.LD5,D0
 MOVE.L D0,D1
 MULU #12,D0
 SWAP D1
 MULU #12,D1
 SWAP D1
 CLR  D1
 ADD.L  D1,D0
 ADD.L  D6,D0
 MOVE.L D7,D1
 MOVE.L D1,D2
 MULU #12,D1
 SWAP D2
 MULU #12,D2
 SWAP D2
 CLR  D2
 ADD.L  D2,D1
 ADD.L  D6,D1
 MOVEA.L  param3(A6),A0
 MOVE.L D5,D2
 MOVE.L D2,D3
 MULU #12,D2
 SWAP D3
 MULU #12,D3
 SWAP D3
 CLR  D3
 ADD.L  D3,D2
 ADD.L  D7,D2
 FMOVE.X  0(A4,D1.L),FP0
 FMUL.X 0(A0,D2.L),FP0
 FADD.X 0(A3,D0.L),FP0
 MOVE.L D5,D0
 MOVE.L D0,D1
 MULU #12,D0
 SWAP D1
 MULU #12,D1
 SWAP D1
 CLR  D1
 ADD.L  D1,D0
 ADD.L  D6,D0
 FMOVE.X FP0,0(A3,D0.L)
 ADDQ.L #1,D7
lao_4 CMP.L D7,D4
 BGE  lao_3

Fortran, optimized
lah_3 MOVE-172(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -142(A6),D2
 MULS.L #12,D2 
 MOVE.L D2,D0
 MOVE -170(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -130(A6),D2
 MULS.L -134(A6),D2 
 ADD.L  D0,D2
 MOVEA.L  32(A6),A0
 ADDA.L D2,A0
 FMOVE.X  (A0),FP7
 MOVE -170(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -118(A6),D2
 MULS.L #12,D2 
 MOVE.L D2,D1
 MOVE -168(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -106(A6),D2
 MULS.L -110(A6),D2 
 ADD.L  D1,D2
 MOVEA.L  24(A6),A1
 ADDA.L D2,A1
 FMUL.X (A1),FP7
 FADD.X -94(A6),FP7
 FMOVE.X  FP7,-94(A6)
 ADDQ #1,-170(A6)
 SUBQ.L #1,D5
 BGT  lah_3

Fortran, plain
lae_3 MOVE-164(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -134(A6),D2
 MULS.L #12,D2 
 MOVE.L D2,D0
 MOVE -162(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -122(A6),D2
 MULS.L -126(A6),D2 
 ADD.L  D0,D2
 MOVEA.L  32(A6),A0
 ADDA.L D2,A0
 FMOVE.X  (A0),FP7 ; get a(i,k)
 MOVE -162(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -110(A6),D2
 MULS.L #12,D2 
 MOVE.L D2,D1
 MOVE -160(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -98(A6),D2
 MULS.L -102(A6),D2 
 ADD.L  D1,D2
 MOVEA.L  24(A6),A1
 ADDA.L D2,A1
 FMUL.X (A1),FP7 ; multiply by b(i,k)
 MOVE -164(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -158(A6),D2
 MULS.L #12,D2 
 MOVE.L D2,D1
 MOVE -160(A6),D2
 EXT.L  D2
 EXT.L  D2
 SUB.L  -146(A6),D2
 MULS.L -150(A6),D2 
 ADD.L  D1,D2
 MOVEA.L  40(A6),A1
 ADDA.L D2,A1
 FADD.X (A1),FP7 ; add c(i,k)
 MOVE -164(A6),D2; this
 EXT.L  D2; whole
 EXT.L  D2; stuff
 SUB.L  -158(A6),D2; is
 MULS.L #12,D2  ;
 MOVE.L D2,D1  ; R
 MOVE -160(A6),D2; E
 EXT.L  D2; D
 EXT.L  D2; U
 SUB.L  -146(A6),D2; N
 MULS.L -150(A6),D2; D
 ADD.L  D1,D2  ; A
 MOVEA.L  40(A6),A1; N
 ADDA.L D2,A1  ; T !!!!
 FMOVE.X  FP7,(A1) ; put back c(i,k)
 ADDQ #1,-162(A6)
 SUBQ.L #1,D5
 BGT  lae_3

 
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Default Folder X attaches a toolbar to the right side of the Open and Save dialogs in any OS X-native application. The toolbar gives you fast access to various folders and commands. You just click... Read more
TinkerTool 5.3 - Expanded preference set...
TinkerTool is an application that gives you access to additional preference settings Apple has built into Mac OS X. This allows to activate hidden features in the operating system and in some of the... Read more
Audio Hijack Pro 2.11.0 - Record and enh...
Audio Hijack Pro drastically changes the way you use audio on your computer, giving you the freedom to listen to audio when you want and how you want. Record and enhance any audio with Audio Hijack... Read more
Intermission 1.1.1 - Pause and rewind li...
Intermission allows you to pause and rewind live audio from any application on your Mac. Intermission will buffer up to 3 hours of audio, allowing users to skip through any assortment of audio... Read more
Autopano Giga 3.6 - Stitch multiple imag...
Autopano Giga allows you to stitch 2, 20, or 2,000 images. Version 3.0 integrates impressive new features that will definitely make you adopt Autopano Pro or Autopano Giga: Choose between 9... Read more

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Traps n’ Gemstones Review
Traps n’ Gemstones Review By Campbell Bird on July 28th, 2014 Our Rating: :: CASTLEVANIA JONESUniversal App - Designed for iPhone and iPad Fight mummies, dig tunnels, and ride a runaway minecart to discover ancient secrets in this... | Read more »
The Phantom PI Mission Apparition Review
The Phantom PI Mission Apparition Review By Jordan Minor on July 28th, 2014 Our Rating: :: GHOSTS BUSTEDUniversal App - Designed for iPhone and iPad The Phantom PI is an exceedingly clever and well-crafted adventure game.   | Read more »
More Stubies Are Coming Your Way in a Ne...
More Stubies Are Coming Your Way in a New Update Posted by Jessica Fisher on July 28th, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
The Great Prank War Review
The Great Prank War Review By Nadia Oxford on July 28th, 2014 Our Rating: :: PRANKING IS SERIOUS BUSINESSUniversal App - Designed for iPhone and iPad Though short, The Great Prank War offers an interesting and fun mix of action and... | Read more »
Marvel Contest of Champions Announced at...
Marvel Contest of Champions Announced at Comic-Con Posted by Jennifer Allen on July 28th, 2014 [ permalink ] Announced over the weekend at San Diego Comic-Con was the fairly exciting looking Marvel Contest of Champions. | Read more »
Teenage Mutant Ninja Turtles Review
Teenage Mutant Ninja Turtles Review By Jennifer Allen on July 28th, 2014 Our Rating: :: DULL SWIPINGUniversal App - Designed for iPhone and iPad The pizza power is weak when it comes to this Teenage Mutant Ninja Turtles game.   | Read more »
Exploration Focused Puzzle Game Beatbudd...
Exploration Focused Puzzle Game Beatbuddy Set to Make Transition from PC to iOS this September Posted by Jennifer Allen on July 28th, 2014 [ permalink ] | Read more »
PlanetHD
PlanetHD By Nadia Oxford on July 28th, 2014 Our Rating: :: SPACE MADNESSUniversal App - Designed for iPhone and iPad PlanetHD will keep players busy for a while, though its unpredictable physics are a handful to deal with.   | Read more »
This Week at 148Apps: July 21-25, 2014
Another Week of Expert App Reviews   At 148Apps, we help you sort through the great ocean of apps to find the ones we think you’ll like and the ones you’ll need. Our top picks become Editor’s Choice, our stamp of approval for apps with that little... | Read more »
Reddme for iPhone - The Reddit Client (...
Reddme for iPhone - The Reddit Client 1.0 Device: iOS iPhone Category: News Price: $.99, Version: 1.0 (iTunes) Description: Reddme for iPhone is an iOS 7-optimized Reddit client that offers a refreshing new way to experience Reddit... | Read more »

Price Scanner via MacPrices.net

13-inch 2.5GHz MacBook Pro on sale for $1099,...
Best Buy has the 13″ 2.5GHz MacBook Pro available for $1099.99 on their online store. Choose free shipping or free instant local store pickup (if available). Their price is $100 off MSRP. Price is... Read more
Roundup of Apple refurbished MacBook Pros, th...
The Apple Store has Apple Certified Refurbished 13″ and 15″ MacBook Pros available for up to $400 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free. Their prices... Read more
Record Mac Shipments In Q2/14 Confound Analys...
A Seeking Alpha Trefis commentary notes that Apple’s fiscal Q3 2014 results released July 22, beat market predictions on earnings, although revenues were slightly lower than anticipated. Apple’s Mac’... Read more
Intel To Launch Core M Silicon For Use In Not...
Digitimes’ Monica Chen and Joseph Tsai, report that Intel will launch 14nm-based Core M series processors specifically for use in fanless notebook/tablet 2-in-1 models in Q4 2014, with many models to... Read more
Apple’s 2014 Back to School promotion: $100 g...
 Apple’s 2014 Back to School promotion includes a free $100 App Store Gift Card with the purchase of any new Mac (Mac mini excluded), or a $50 Gift Card with the purchase of an iPad or iPhone,... Read more
iMacs on sale for $150 off MSRP, $250 off for...
Best Buy has iMacs on sale for up to $160 off MSRP for a limited time. Choose free home shipping or free instant local store pickup (if available). Prices are valid for online orders only, in-store... Read more
Mac minis on sale for $100 off MSRP, starting...
Best Buy has Mac minis on sale for $100 off MSRP. Choose free shipping or free instant local store pickup. Prices are for online orders only, in-store prices may vary: 2.5GHz Mac mini: $499.99 2.3GHz... Read more
Global Tablet Market Grows 11% in Q2/14 Notwi...
Worldwide tablet sales grew 11.0 percent year over year in the second quarter of 2014, with shipments reaching 49.3 million units according to preliminary data from the International Data Corporation... Read more
New iPhone 6 Models to Have Staggered Release...
Digitimes’ Cage Chao and Steve Shen report that according to unnamed sources in Apple’s upstream iPhone supply chain, the new 5.5-inch iPhone will be released several months later than the new 4.7-... Read more
New iOS App Helps People Feel Good About thei...
Mobile shoppers looking for big savings at their favorite stores can turn to the Goodshop app, a new iOS app with the latest coupons and deals at more than 5,000 online stores. In addition to being a... Read more

Jobs Board

*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Sr. Product Leader, *Apple* Store Apps - Ap...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
WW Sales Program Manager, *Apple* Online St...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
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