similar to: [LLVMdev] FW: question about malloc call vs. instruction

I'm forwarding this question to llvmdev: -----Original Message----- From: lee white baugh [mailto:leebaugh at students.uiuc.edu] Sent: Wednesday, September 11, 2002 1:27 AM To: Vikram S. Adve Subject: RE: mp1 i'll attempt to address the issues i raised in my long email as i am able. as i said i have figured out the worklist thing, and am happy to report that i've negotiated lots of

Hello! I'm compiling code which uses pointers as iterators. For some reason--probably a silly misunderstanding of the docs--I can't eliminate duplicate pointer loads. I'll probably figure this out eventually, but if somebody else sees the answer instantly, I certainly won't complain. :-) Here are the optimizers I'm running: opt -f -simplifycfg -dce -instcombine

On Thu, 16 Mar 2006, Eric Kidd wrote: > Hello! I'm compiling code which uses pointers as iterators. For some > reason--probably a silly misunderstanding of the docs--I can't eliminate > duplicate pointer loads. I'll probably figure this out eventually, but if > somebody else sees the answer instantly, I certainly won't complain. :-) There are no stupid questions.

On Mar 16, 2006, at 8:47 PM, Chris Lattner wrote: > On Thu, 16 Mar 2006, Eric Kidd wrote: >> The duplicate loads appear at the top of the %regex6 and %regex2 >> blocks below. I've tried various alias analysis implementations >> either alone or in combination. > > LICM doesn't remove common subexpressions, also -load-vn doesn't > affect LICM. Try

Hi, i have some code that allocate some memory, store the pointer to a variable, read it back and deallocates it, like this: int %main(int %argc, ubyte** %argv) { %c_19 = alloca ubyte* %malloc_206 = malloc ubyte, uint 10 store ubyte* %malloc_206, ubyte** %c_19 %tmp_207 = load ubyte** %c_19 free ubyte* %tmp_207 ret int 0 } i expected the optimized to remove everything, but after running it the

On Tue, 13 Feb 2007, Nicola Lugato wrote: > Hi, i have some code that allocate some memory, store the pointer to a > variable, read it back and deallocates it, like this: ok > i expected the optimized to remove everything, but after running it > the code i get is: > > int %main(int %argc, ubyte** %argv) { > %malloc_206 = malloc [10 x ubyte] > %malloc_206.sub =

I've made some other test and it looks like it don't remove even simple malloc/free couple. Maybe there's something wrong in the way i use the opt command. How can i tell him to optimize at best, whitout specifing each pass? I'm not using c/c++ frontend, just the assembler. Thanks in advance On 2/14/07, Chris Lattner <sabre at nondot.org> wrote: > On Tue, 13 Feb 2007,

Hi Nicola, On Wed, 2007-02-14 at 18:54 +0100, Nicola Lugato wrote: > I've made some other test and it looks like it don't remove even > simple malloc/free couple. Maybe there's something wrong in the way i > use the opt command. No, there's not. LLVM doesn't provide the transform you want. As Chris mentioned, if you open a Bugzilla report (http://llvm.org/bugs) and

I tried to make my pass dynamically loadable cause it's too slow to compile the whole system. I copied the Makefile from Hello directory and changed the name. But when I type 'gmake' under the directory of my pass. I always got the following error message. I cannot figure out why. Can you have a look and let me know how to fix it? thanks a lot, xiaodong

Anders Alexandersson wrote: > Hello! > > I get some odd behaviour using my structs: > > "myKernelMap" = type {int (sbyte*)*, int ()*} > "Kernel" = type {"myKernelMap"*} > > The second member ( int()* ) is a pointer to the %getchar() function. > > I want to call getchar using this function: > > int

Hello! I get some odd behaviour using my structs: "myKernelMap" = type {int (sbyte*)*, int ()*} "Kernel" = type {"myKernelMap"*} The second member ( int()* ) is a pointer to the %getchar() function. I want to call getchar using this function: int "callmyKernelgetchar_kernel"("Kernel"* "myKernel") { "PTRMAP" =

int %nlz10(uint %param.x) { %.t3 = shr uint %param.x, ubyte 1 ; <uint> [#uses=1] %.t4 = or uint %.t3, %param.x ; <uint> [#uses=2] %.t7 = shr uint %.t4, ubyte 2 ; <uint> [#uses=1] %.t8 = or uint %.t7, %.t4 ; <uint> [#uses=2] %.t11 = shr uint %.t8, ubyte 4 ; <uint> [#uses=1]

%TCDef = type { [16 x ubyte], [16 x ubyte], [16 x ubyte], [16 x ubyte], [64 x ubyte], ushort, %anonymous.5, %anonymous.5, %anonymous.5, uint, uint, uint, ushort, uint, uint, uint, uint } %anonymous.5 = type { ubyte, ubyte, ubyte, ubyte } I have a parser that reads LL files but doesn't handle forward references to structure types. I've been using 1.9 for quite a while and have just now

Hi, I've another question about getelementptr. So, in the twisted mind of my little pass, I have a statement like this: %reg228-mod = getelementptr %struct.SimpleStruct* %N.1, long 0 ; <%struct.SimpleStruct*> [#uses=2] I'm not sure of the semantics of %a = getelementptr %b, long 0. I want to think that it is some kind of weird identity (no-op), judging from the operand

You are correct, ubyte 2 simply means 3rd element of the structure. This quantity is always constant (it specifies the field number), so we could have used any signed or unsigned integer type for it instead of ubyte. UByte means we are limited to at most 256 structure fields but it also makes the bytecode representation more compact. (To remove this restriction, we may migrate to UInt in the

I have a question about GetElementPtr. Suppose I have an GetElementPtr Instruction GI: %reg = getelementptr %ST* %s, uint 1, ubyte 2, ubyte 1, uint 5, uint 13 I want to check if this is the reference of a component of a structure, how can I do that? Should I check which operand of this instruction is 'ubyte' type? How can I do that in code? should I use ubyte *a =

Dear LLVMdev, As far as I can tell, what the "ubyte 2" value really means is the 2+1'th member of the structure...regardless of whether that structure's 3rd element actually starts at (pointer to structure) + 3*sizeof(ubyte) or not. So, is there any semantic connection between "ubyte" as used in structure accesses and what getelementptr actually interprets it as? Or

I'm seeing Asterisk crashes with the following frame at func_speex.c:188: (gdb) p *frame $6 = {frametype = AST_FRAME_VOICE, subclass = {integer = 0, format = 0xe2f9e20, frame_ending = 0}, datalen = 0, samples = 640, mallocd = 1, mallocd_hdr_len = 232, offset = 64, src = 0x2ac07413e7f8 "siren14tolin32", data = {ptr = 0x3cab9378, uint32 = 1017877368, pad =

On Mon, 3 May 2004, Anders Alexandersson wrote: > Hello! > > I'm having trouble with pointer traversing. I have a design as follows: > class -> map -> classFunctions > > Starting with a pointer to the class, I want to get a pointer to a > classFunction via a pointer to the map. Okay... > I can't get that function pointer! > > How shall I think to get

Hi all, I put a case into llvm and got the following .ll code: ... %r1419_0_0_0_i376 = alloca i32 ; <i32*> [#uses=2] ... %tmp1476_i = lshr i32 %tmp1226_i, 24 ; <i32> [#uses=1] store i32 %tmp1476_i, i32* %r1419_0_0_0_i376, align 4 %tmp1505_i = volatile load i32* %r1419_0_0_0_i376, align 4 ; <i32> [#uses=1] %tmp1542_i = getelementptr [256 x i8]* @Te, i32 0, i32 %tmp1505_i ...