similar to: [LLVMdev] Frame index arithmetic

On Jan 17, 2010, at 2:56 AM, Mark Muir wrote: > I've developed a working back-end for a custom architecture, based on LLVM 2.6. I'm now trying to cover more of the unique features of this architecture. > > To make use of one such feature, I'm trying something cunning/crazy with the stack - implementing it in a type of memory that can only be addressed via immediates. >

>> I'm trying something cunning/crazy with the stack - implementing it in a type of memory that can only be addressed via immediates. >> >> I've got this mostly working. However, I came across a problem which I've been unable to work around: lowering the IR (even without any optimisations enabled) often requires the pattern: >> >> i32 = FrameIndex

Hi everyone, I'm having some trouble with my ifelse statements. I'm trying to put 12 conditions within 3 groups. Here is the code I have so far: dat$cond <- ifelse(test = dat$cond == "cond1" | dat$cond == "cond2" | dat$cond == "cond3" dat$cond == "cond4" yes = "Uniform" no = ifelse(test =

Hi, The phase of instruction combine cannot handle the instruction %4 = select i1 %tobool.i, metadata !12, metadata !10 generated by the phase of CFG simplification and the compiler generates an assertion failure. I wonder whether this is valid LLVM IR: %4 = select i1 %tobool.i, metadata !12, metadata !10 Before CFGSimplify cond.true.i: ; preds = %entry

On Thu, Sep 4, 2008 at 8:39 AM, Nuno Lopes <nunoplopes at sapo.pt> wrote: > Hi, > > I have two questions about optimizations performed by llvm. > > Consider these simple functions: > int x(int b) { return b?4:6; } > int y() { return x(0); } > > int x2() { return 5; } > int y2() { return x2(); } > > the optimized bitcode (with clang + opt

To reproduce the issue, please use the command line "opt -simplifycfg filename". target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-unknown-linux-gnu" %struct.G = type { %struct.ordered_index_node*, i32 } %struct.ordered_index_node = type { %struct.B, %struct.F } %struct.B = type { i32 } %struct.F = type { i32*, i32* }

Hi, I have two questions about optimizations performed by llvm. Consider these simple functions: int x(int b) { return b?4:6; } int y() { return x(0); } int x2() { return 5; } int y2() { return x2(); } the optimized bitcode (with clang + opt -std-compiler-opts) is: define i32 @y(...) nounwind { entry: ret i32 6 } define i32 @y2(...) nounwind { entry: %call = call i32 (...)* @x2( ) ;

Hi! before InstCombine (llvm::createInstructionCombiningPass()) I have a trunc from i8 to i1 and then a select: %45 = load i8* @myGlobal, align 1 %tobool = trunc i8 %45 to i1 %cond = select i1 %tobool, float 1.000000e+00, float -1.000000e+00 after instCombine I have: %29 = load i8* @myGlobal, align 1 %30 = and i8 %29, 1 %tobool = icmp ne i8 %30, 0 %cond = select i1 %tobool, float 1.000000e+00,

Not a reproducible example, so a bit of guessing here, but a) don't try to assign results to variables inside the ifelse. That is, remove all the single-equals signs and "test" variables. If you really need to conditionally assign variables then use "if"... but chances are good you don't need that. b) "closure" is effectively another word

Dear R users, I have a matrix a and a classification vector b such that > str(a) num [1:50, 1:800000] and > str(b) Factor w/ 3 levels "cond1","cond2","cond3" I'd like to do an anova on all 800000 columns and record the F statistic for each test; I currently do this using f.stat.vec <- numeric(length(a[1,]) for (i in 1:length(a[1,]) { f.test.frame

Thanks Anton and Krzysztof! Here is the dump using the -debug flag. At this point I am not making much sense of this, would it be too much to ask if one of you could walk me through one of these lines? One thing that I didn't point out is that I never defined any separate floating point registers, not sure if this will pose any issue? Thanks again for your time! Jeff jeff at

>> Hi! >> >> before InstCombine (llvm::createInstructionCombiningPass()) I have >> a trunc from i8 to i1 and then a select: >> >> %45 = load i8* @myGlobal, align 1 >> %tobool = trunc i8 %45 to i1 >> %cond = select i1 %tobool, float 1.000000e+00, float -1.000000e+00 >> >> after instCombine I have: >> >> %29 = load i8*

Hi, I am having issues running a new backend that I created for a new architecture. I suspect these errors may have something to do with how I have the string setup in LLVMTargetMachine() below? Also - It would be great if someone could point me to a document that describes some of these error messages? For example what does t26 ..t4 mean? Thanks in advance for taking your valuable time to help

On Dec 27, 2011, at 5:09 AM, Jochen Wilhelmy wrote: > Hi! > > before InstCombine (llvm::createInstructionCombiningPass()) I have > a trunc from i8 to i1 and then a select: > > %45 = load i8* @myGlobal, align 1 > %tobool = trunc i8 %45 to i1 > %cond = select i1 %tobool, float 1.000000e+00, float -1.000000e+00 > > after instCombine I have: > > %29 = load i8*

Hi the appended IR code does not optimize to my liking :) this is the interesting part in x86_64, that got produced via clang -Os: --- movq -16(%r12), %rax movl -4(%rax), %ecx andl $2298949, %ecx ## imm = 0x231445 cmpq $2298949, (%rax,%rcx) ## imm = 0x231445 leaq 8(%rax,%rcx), %rax cmovneq %r15, %rax movl $2298949, %esi ## imm = 0x231445 movq %r12, %rdi movq %r14,

This is the right answer for C's alloca. The question probably referred to LLVM IR's alloca, however. On Aug 13, 2008, at 11:07 AMPDT, Mike Stump wrote: > On Aug 13, 2008, at 10:49 AM, John Criswell wrote: >> Is it legal to have an alloca in a basic block other than a >> function's entry block? > > How else could you generate code for: > > #include

Hello, What follows is my attempt to describe how poison works. Let me know what you think. -- David # LLVM Poison Semantics Poison is an LLVM concept which exists solely to enable further optimization of LLVM IR. The exact behavior of poison has been, to say the least, confusing for users, researchers and engineers working with LLVM. This document hopes to clear up some of the confusion

I think Chris is saying that the and is necessary because with your i1 trunc you're ignoring all of the high bits. The and implements that. If you don't want this behavior, don't generate the trunc in the first place and just compare the full width to zero. Reid On Wed, Dec 28, 2011 at 6:45 AM, Jochen Wilhelmy <j.wilhelmy at arcor.de>wrote: > > >> Hi! >

Using Clang/LLVM 3.6.0 we are observing a case where the optimizations are clobbering EFLAGS on x86_64. This is inconvenient when the status of bit 9 (IF), which controls interrupts, changes. Here's a simple test program. Assume that the external function foo() modifies the IF bit in EFLAGS. --- #include <stdlib.h> #include <stdbool.h> void foo(void); int a; int bar(void)

Dear list, I want to extract pairs of values out of a dataframe where one criteria/condition does match. I have an experiment with 3 conditions which were not always applied: e.g.: group cond x A 1 2 A 2 4 A 3 6.5 B 1 3 B 2 4.5 C 1 2.5 C 3 4 D 2 5 D 3