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108 Commits

Author SHA1 Message Date
Nate Begeman
486ebfd704 Fix Shootout-C++/wc, which was broken by my recent changes to emit fewer 
reg-reg copies.  The necessary conditions for this bug are a GEP that is
used outside the basic block in which it is defined, whose components
other than the pointer are all constant zero, and where the use is
selected before the definition (backwards branch to successsor block).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@18084 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-21 05:14:06 +00:00
Nate Begeman
bc3a5378d0 Eliminate another 6k register copies that the register allocator would just 
coalesce out of hbd.  Speeds up compilation by 2% (0.6s)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17987 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-19 08:01:16 +00:00
Nate Begeman
8531f6f42a Generate fewer reg-reg copies for the register allocator to deal with. 
This eliminates over 2000 in hbd alone.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17973 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-19 02:06:40 +00:00
Nate Begeman
db869aad8c Eliminate another common source of moves that the register allocator 
shouldn't be forced to coalesce for us: folded GEP operations.  This too
fires thousands of times across the testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17947 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-18 07:22:46 +00:00
Nate Begeman
1f5308e5b5 When accessing the base register for global variables, use the register 
directly rather than making a copy for the register allocator to coalesce.
This kills thousands of live intervals across the testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17946 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-18 06:51:29 +00:00
Nate Begeman
0113638073 Clean up and fix cast codegen by removing cases that are handled elsewhere, 
and properly emitting signed short to unsigned int.  This fixes the last
regression vs. the CBE, MultiSource/Applications/hbd.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17942 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-18 04:56:53 +00:00
Nate Begeman
676dee6ae9 Put int the getReg cast optimization from x86 so that we generate fewer 
move instructions for the register allocator to coalesce.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17608 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-08 02:25:40 +00:00
Nate Begeman
075cdc655e Disable bogus cast elimination when the cast is used by a setcc instruction. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17583 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-07 20:23:42 +00:00
Nate Begeman
28dd2fc240 Thanks to sabre for pointing out that we were incorrectly codegen'ing 
int test(int x) { return 32768 - x; }

Fixed by teaching the function that checks a constant's validity to be used
as an immediate argument about subtract-from instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17476 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-11-04 19:43:18 +00:00
Nate Begeman
9b508c3619 Fix treecc. Also fix a latent bug in emitBinaryConstOperation that would 
allow and const, 0 to be incorrectly codegen'd into a rlwinm instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17234 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-26 03:48:25 +00:00
Nate Begeman
905a29152f Implement more complete and correct codegen for bitfield inserts, as tested 
by the recently committed rlwimi.ll test file.  Also commit initial code
for bitfield extract, although it is turned off until fully debugged.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17207 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-24 10:33:30 +00:00
Nate Begeman
31dfc52b81 Kill casts from integer types to unsigned byte, when the cast was only used 
as the shift amount operand to a shift instruction.  This was causing us to
emit unnecessary clear operations for code such as:
int foo(int x) { return 1 << x; }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17175 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-23 00:50:23 +00:00
Reid Spencer
8c2c3152d6 Adjust to changes in Makefile.rules 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17167 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-22 21:02:08 +00:00
Nate Begeman
0797d4905a Don't clear or sign extend bool->int. This fires a few dozen times on the test suite 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17147 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-20 21:55:41 +00:00
Nate Begeman
1b75022cd3 Implement bitfield insert by recognizing the following pattern: 
1. optional shift left
2. and x, immX
3. and y, immY
4. or z, x, y
==> rlwimi z, x, y, shift, mask begin, mask end

where immX == ~immY and immX is a run of set bits. This transformation
fires 32 times on voronoi, once on espresso, and probably several
dozen times on external benchmarks such as gcc.

To put this in terms of actual code generated for
struct B { unsigned a : 3; unsigned b : 2; };
void storeA (struct B *b, int v) { b->a = v;}
void storeB (struct B *b, int v) { b->b = v;}

Old:
_storeA:
        rlwinm r2, r4, 0, 29, 31
        lwz r4, 0(r3)
        rlwinm r4, r4, 0, 0, 28
        or r2, r4, r2
        stw r2, 0(r3)
        blr

_storeB:
        rlwinm r2, r4, 3, 0, 28
        rlwinm r2, r2, 0, 27, 28
        lwz r4, 0(r3)
        rlwinm r4, r4, 0, 29, 26
        or r2, r2, r4
        stw r2, 0(r3)
        blr

New:
_storeA:
        lwz r2, 0(r3)
        rlwimi r2, r4, 0, 29, 31
        stw r2, 0(r3)
        blr

_storeB:
        lwz r2, 0(r3)
        rlwimi r2, r4, 3, 27, 28
        stw r2, 0(r3)
        blr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17078 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-17 05:19:20 +00:00
Nate Begeman
2d4c98d79b Finally fix one of the oldest FIXMEs in the PowerPC backend: correctly 
flag rotate left word immediate then mask insert (rlwimi) as a two-address
instruction, and update the ISel usage of the instruction accordingly.

This will allow us to properly schedule rlwimi, and use it to efficiently
codegen bitfield operations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17068 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-16 20:43:38 +00:00
Chris Lattner
289a49ab7d ADd support for undef and unreachable 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17050 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-16 18:13:47 +00:00
Nate Begeman
e0c83a86b0 Better codegen of binary integer ops with 32 bit immediate operands. 
This transformation fires a few dozen times across the testsuite.

For example, int test2(int X) { return X ^ 0x0FF00FF0; }
Old:
_test2:
        lis r2, 4080
        ori r2, r2, 4080
        xor r3, r3, r2
        blr

New:
_test2:
        xoris r3, r3, 4080
        xori r3, r3, 4080
        blr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17004 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-15 00:50:19 +00:00
Nate Begeman
bdf69847a9 Implement logical and with an immediate that consists of a contiguous block 
of one or more 1 bits (may wrap from least significant bit to most
significant bit) as the rlwinm rather than andi., andis., or some longer
instructons sequence.

int andn4(int z) { return z & -4; }
int clearhi(int z) { return z & 0x0000FFFF; }
int clearlo(int z) { return z & 0xFFFF0000; }
int clearmid(int z) { return z & 0x00FFFF00; }
int clearwrap(int z) { return z & 0xFF0000FF; }

_andn4:
        rlwinm r3, r3, 0, 0, 29
        blr

_clearhi:
        rlwinm r3, r3, 0, 16, 31
        blr

_clearlo:
        rlwinm r3, r3, 0, 0, 15
        blr

_clearmid:
        rlwinm r3, r3, 0, 8, 23
        blr

_clearwrap:
        rlwinm r3, r3, 0, 24, 7
        blr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16832 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-08 02:49:24 +00:00
Nate Begeman
b816f0298d Several fixes and enhancements to the PPC32 backend. 
1. Fix an illegal argument to getClassB when deciding whether or not to
   sign extend a byte load.

2. Initial addition of isLoad and isStore flags to the instruction .td file
   for eventual use in a scheduler.

3. Rewrite of how constants are handled in emitSimpleBinaryOperation so
   that we can emit the PowerPC shifted immediate instructions far more
   often.  This allows us to emit the following code:

int foo(int x) { return x | 0x00F0000; }

_foo:
.LBB_foo_0:     ; entry
        ; IMPLICIT_DEF
        oris r3, r3, 15
        blr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16826 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-07 22:30:03 +00:00
Chris Lattner
7c348e1c9f Correct some typeos 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16770 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-06 16:28:24 +00:00
Nate Begeman
35b020df39 Turning on fsel code gen now that we can do so would be good. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16765 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-06 11:03:30 +00:00
Nate Begeman
087d5d92f1 Implement floating point select for lt, gt, le, ge using the powerpc fsel 
instruction.

Now, rather than emitting the following loop out of bisect:
.LBB_main_19:	; no_exit.0.i
	rlwinm r3, r2, 3, 0, 28
	lfdx f1, r3, r27
	addis r3, r30, ha16(.CPI_main_1-"L00000$pb")
	lfd f2, lo16(.CPI_main_1-"L00000$pb")(r3)
	fsub f2, f2, f1
	addis r3, r30, ha16(.CPI_main_1-"L00000$pb")
	lfd f4, lo16(.CPI_main_1-"L00000$pb")(r3)
	fcmpu cr0, f1, f4
	bge .LBB_main_64	; no_exit.0.i
.LBB_main_63:	; no_exit.0.i
	b .LBB_main_65	; no_exit.0.i
.LBB_main_64:	; no_exit.0.i
	fmr f2, f1
.LBB_main_65:	; no_exit.0.i
	addi r3, r2, 1
	rlwinm r3, r3, 3, 0, 28
	lfdx f1, r3, r27
	addis r3, r30, ha16(.CPI_main_1-"L00000$pb")
	lfd f4, lo16(.CPI_main_1-"L00000$pb")(r3)
	fsub f4, f4, f1
	addis r3, r30, ha16(.CPI_main_1-"L00000$pb")
	lfd f5, lo16(.CPI_main_1-"L00000$pb")(r3)
	fcmpu cr0, f1, f5
	bge .LBB_main_67	; no_exit.0.i
.LBB_main_66:	; no_exit.0.i
	b .LBB_main_68	; no_exit.0.i
.LBB_main_67:	; no_exit.0.i
	fmr f4, f1
.LBB_main_68:	; no_exit.0.i
	fadd f1, f2, f4
	addis r3, r30, ha16(.CPI_main_2-"L00000$pb")
	lfd f2, lo16(.CPI_main_2-"L00000$pb")(r3)
	fmul f1, f1, f2
	rlwinm r3, r2, 3, 0, 28
	lfdx f2, r3, r28
	fadd f4, f2, f1
	fcmpu cr0, f4, f0
	bgt .LBB_main_70	; no_exit.0.i
.LBB_main_69:	; no_exit.0.i
	b .LBB_main_71	; no_exit.0.i
.LBB_main_70:	; no_exit.0.i
	fmr f0, f4
.LBB_main_71:	; no_exit.0.i
	fsub f1, f2, f1
	addi r2, r2, -1
	fcmpu cr0, f1, f3
	blt .LBB_main_73	; no_exit.0.i
.LBB_main_72:	; no_exit.0.i
	b .LBB_main_74	; no_exit.0.i
.LBB_main_73:	; no_exit.0.i
	fmr f3, f1
.LBB_main_74:	; no_exit.0.i
	cmpwi cr0, r2, -1
	fmr f16, f0
	fmr f17, f3
	bgt .LBB_main_19	; no_exit.0.i

We emit this instead:
.LBB_main_19:	; no_exit.0.i
	rlwinm r3, r2, 3, 0, 28
	lfdx f1, r3, r27
	addis r3, r30, ha16(.CPI_main_1-"L00000$pb")
	lfd f2, lo16(.CPI_main_1-"L00000$pb")(r3)
	fsub f2, f2, f1
	fsel f1, f1, f1, f2
	addi r3, r2, 1
	rlwinm r3, r3, 3, 0, 28
	lfdx f2, r3, r27
	addis r3, r30, ha16(.CPI_main_1-"L00000$pb")
	lfd f4, lo16(.CPI_main_1-"L00000$pb")(r3)
	fsub f4, f4, f2
	fsel f2, f2, f2, f4
	fadd f1, f1, f2
	addis r3, r30, ha16(.CPI_main_2-"L00000$pb")
	lfd f2, lo16(.CPI_main_2-"L00000$pb")(r3)
	fmul f1, f1, f2
	rlwinm r3, r2, 3, 0, 28
	lfdx f2, r3, r28
	fadd f4, f2, f1
	fsub f5, f0, f4
	fsel f0, f5, f0, f4
	fsub f1, f2, f1
	addi r2, r2, -1
	fsub f2, f1, f3
	fsel f3, f2, f3, f1
	cmpwi cr0, r2, -1
	fmr f16, f0
	fmr f17, f3
	bgt .LBB_main_19	; no_exit.0.i


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16764 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-10-06 09:53:04 +00:00
Nate Begeman
1f49e868aa Generate better code by being far less clever when it comes to the select instruction. Don't create overlapping register lifetimes 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16580 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-29 05:00:31 +00:00
Nate Begeman
1b99fd3e8a improve Type::BoolTy codegen by eliminating unnecessary clears and sign extends 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16578 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-29 03:45:33 +00:00
Nate Begeman
a41fc77ae4 To go along with sabre's improved InstCombining, improve recognition of 
integers that we can use as immediate values in instructions.

Example from yacr2:
-       lis r10, -1
-       ori r10, r10, 65535
-       add r28, r28, r10
+       addi r28, r28, -1
        addi r7, r7, 1
        addi r9, r9, 1
        b .LBB_main_9   ; loopentry.1.i214


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16566 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-29 02:35:05 +00:00
Nate Begeman
da721e74f8 Correct some BuildMI arguments for the upcoming simple scheduler 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16519 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-27 05:08:17 +00:00
Nate Begeman
645495d2e6 Fix the last of the major PPC GEP folding deficiencies. This will allow 
the ISel to use indexed and non-zero immediate offsets for GEPs that have
more than one use.  This is common for instruction sequences such as a load
followed by a modify and store to the same address.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16493 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-23 05:31:33 +00:00
Nate Begeman
a2de102a5b add optimized code sequences for setcc x, 0 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16478 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-22 04:40:25 +00:00
Misha Brukman
a1dca55a3a s/ISel/PPC32ISel/ to have unique class names for debugging via gdb because the 
C++ front-end in gcc does not mangle classes in anonymous namespaces correctly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16470 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-21 18:22:19 +00:00
Nate Begeman
ed42853be1 All PPC instructions are now auto-printed 
32 and 64 bit AsmWriters unified
Darwin and AIX specific features of AsmWriter split out


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16163 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-04 05:00:00 +00:00
Nate Begeman
b7a8f2cdaa Convert remaining X-Form and Pseudo instructions over to asm writer 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16142 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-02 08:13:00 +00:00
Reid Spencer
551ccae044 Changes For Bug 352 
Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16137 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-09-01 22:55:40 +00:00
Nate Begeman
f2f0781a10 Implement the following missing functionality in the PPC backend: 
cast fp->bool
cast ulong->fp
algebraic right shift long by non-constant value
These changes tested across most of the test suite.  Fixes Regression/casts


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16081 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-29 08:19:32 +00:00
Nate Begeman
0e5e5f56bd Kill a majority of unnecessary sign extensions for byte loads 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15991 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-22 08:10:15 +00:00
Nate Begeman
a96c4af7f1 Back out branchless SetCC code. While it helped a lot in some cases, it 
hurt a lot in others.  Instead, improve branching version of SetCC and
Select instructions.  The old code will be in CVS should we ever need to
dig it up again.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15979 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-21 20:42:14 +00:00
Nate Begeman
b47321ba2b Implement code to convert SetCC into straight line code where appropriate. Add necessary instructions for this transformation to the .td file. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15952 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-20 09:56:22 +00:00
Misha Brukman
d2cbb871d0 This PHI has 4 additional operands, not 2. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15926 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-19 21:00:12 +00:00
Nate Begeman
1e67d4d7ba Convert casts that will have no effect into move instructions. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15914 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-19 08:07:50 +00:00
Nate Begeman
81d265d692 Clean up floating point instruction selection. 
Change int->float cast code to put conversion constants in constant pool.
Shorten code sequence for constant pool fp loads.
Remove LOADLoDirect/LOADLoIndirect psuedo instructions and tweak asmwriter


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15913 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-19 05:20:54 +00:00
Nate Begeman
07a73755d3 Re-fix hiding the Frame Pointer from the register allocator in functions 
that have a frame pointer.  This change fixes Burg.  In addition, make
the necessary changes to floating point code gen and constant loading after
Chris Lattner's fixes to the asm writer.  These changes fix MallocBench/gs


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15873 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-17 07:17:44 +00:00
Misha Brukman
f2ccb77ee9 PowerPC 32-/64-bit split: Part I, PPC32* bit files, adapted from former PowerPC* 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15850 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-17 04:55:41 +00:00
Nate Begeman
865075ed35 Fix mismatched adjust down/up of SP in functions that contain variable 
sized allocas.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15806 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-16 01:50:22 +00:00
Nate Begeman
43d64eae53 Fix float to int codepath by always allocating 8 bytes for the target of a double store; optimize cmplwi generation. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15759 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-15 06:42:28 +00:00
Nate Begeman
6d1e2dfd86 Fix handling of FP constants with single precision, and loading of internal linkage function addresses 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15742 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-14 22:11:38 +00:00
Nate Begeman
b73a711ed7 Fix siod by switching BoolTy to byte rather than int until CFE changes for 
Darwin.  Also, change asm printer to output proper stubs for external
functions whose address is passed as an argument to aid in bugpointing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15721 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-13 09:32:01 +00:00
Nate Begeman
293d88ca8b Fix 177.mesa compilation, don't use floating point regs for base addresses! 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15720 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-13 04:45:14 +00:00
Nate Begeman
8cfa427d9c Fix llc crasher compiling siod by giving BuildMI the correct number of arguments 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15719 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-13 03:56:49 +00:00
Nate Begeman
7a4fe9be7e Clean up 32/64bit and Darwin/AIX split. Next steps: 64 bit ISel, AIX asm printer. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15662 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-11 07:40:04 +00:00
Chris Lattner
74a806cd3d Fix a case where constantexprs could leak into the PPC isel. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15661 91177308-0d34-0410-b5e6-96231b3b80d8
 2004-08-11 07:34:50 +00:00