Chris Lattner
2636c1be17
*FINALLY* Fix a really nasty nondeterministic bug that has been haunting us
...
since May 1st. In this code, the pred iterator was being invalidated sometimes
causing the wrong entries to be added to PHI nodes.
The fix for this is to defererence and safe the *PI value before we hack on
branch instructions, which changes use/def chains, which SOMETIMES invalidates
the iterator.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14278 91177308-0d34-0410-b5e6-96231b3b80d8
2004-06-21 07:19:01 +00:00
Chris Lattner
218a8223e6
Add some DEBUG output to the simplifycfg routines
...
Fix another non-deterministic behavior, this one should actually speed up the
code though as it was doing silly things.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14258 91177308-0d34-0410-b5e6-96231b3b80d8
2004-06-20 01:13:18 +00:00
Chris Lattner
1654cff8e8
Do not sort by the address of LLVM ConstantInt* objects. This produces
...
nondeterministic results that depend on where these objects land in memory.
Instead, sort by the value of the constant, which is stable.
Before this patch, the -simplifycfg pass run from two different compilers
could cause different code to be generated, though it was semantically the
same:
@@ -12258,8 +12258,8 @@
%s_addr.1 = phi sbyte* [ %s, %entry ], [ %inc.0, %no_exit ] ; <sbyte*> [#uses=5]
%tmp.1 = load sbyte* %s_addr.1 ; <sbyte> [#uses=1]
switch sbyte %tmp.1, label %no_exit [
- sbyte 0, label %loopexit
sbyte 46, label %loopexit
+ sbyte 0, label %loopexit
]
We need to stomp all of this stuff out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14243 91177308-0d34-0410-b5e6-96231b3b80d8
2004-06-19 07:02:14 +00:00
Chris Lattner
bdcc0b8c55
Do not clone arbitrary condition instructions.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13316 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-02 05:19:36 +00:00
Chris Lattner
12fe2b1b82
Do not infinitely "unroll" single BB loops.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13315 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-02 05:02:03 +00:00
Chris Lattner
a1f79fb08b
Dont' merge terminators that are needed to select PHI node values.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13312 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-02 01:00:44 +00:00
Chris Lattner
e67fa05036
Implement SimplifyCFG/branch-cond-merge.ll
...
Turning "if (A < B && B < C)" into "if (A < B & B < C)"
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13311 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-01 23:35:43 +00:00
Chris Lattner
951fdb9764
Fix my missing parens
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13307 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-01 22:41:51 +00:00
Chris Lattner
92da2c2053
Implement SimplifyCFG/branch-cond-prop.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13306 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-01 22:36:37 +00:00
Chris Lattner
570751c2a7
Fold code like:
...
if (C)
V1 |= V2;
into:
Vx = V1 | V2;
V1 = select C, V1, Vx
when the expression can be evaluated unconditionally and is *cheap* to
execute. This limited form of if conversion is quite handy in lots of cases.
For example, it turns this testcase into straight-line code:
int in0 ; int in1 ; int in2 ; int in3 ;
int in4 ; int in5 ; int in6 ; int in7 ;
int in8 ; int in9 ; int in10; int in11;
int in12; int in13; int in14; int in15;
long output;
void mux(void) {
output =
(in0 ? 0x00000001 : 0) | (in1 ? 0x00000002 : 0) |
(in2 ? 0x00000004 : 0) | (in3 ? 0x00000008 : 0) |
(in4 ? 0x00000010 : 0) | (in5 ? 0x00000020 : 0) |
(in6 ? 0x00000040 : 0) | (in7 ? 0x00000080 : 0) |
(in8 ? 0x00000100 : 0) | (in9 ? 0x00000200 : 0) |
(in10 ? 0x00000400 : 0) | (in11 ? 0x00000800 : 0) |
(in12 ? 0x00001000 : 0) | (in13 ? 0x00002000 : 0) |
(in14 ? 0x00004000 : 0) | (in15 ? 0x00008000 : 0) ;
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12798 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 22:50:22 +00:00
Chris Lattner
7aa773bc07
Fix the obvious bug in my previous checkin
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12618 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-02 18:15:10 +00:00
Chris Lattner
147af6b75f
Implement Transforms/SimplifyCFG/return-merge.ll
...
This actually causes us to turn code like:
return C ? A : B;
into a select instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12617 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-02 18:13:43 +00:00
Chris Lattner
552112f2f8
Now that all the code generators support the select instruction, and the instcombine
...
pass can eliminate many nasty cases of them, start generating them in the optimizers
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12545 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-30 19:44:05 +00:00
Chris Lattner
7acd1ccb8a
Fix compilation of mesa, which I broke earlier today
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12465 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-17 02:02:47 +00:00
Chris Lattner
4bebf08d15
Do not copy gigantic switch instructions
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12441 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-16 19:45:22 +00:00
Chris Lattner
542f149f00
Implement switch->br and br->switch folding by ripping out the switch->switch
...
and br->br code and generalizing it. This allows us to compile code like this:
int test(Instruction *I) {
if (isa<CastInst>(I))
return foo(7);
else if (isa<BranchInst>(I))
return foo(123);
else if (isa<UnwindInst>(I))
return foo(1241);
else if (isa<SetCondInst>(I))
return foo(1);
else if (isa<VAArgInst>(I))
return foo(42);
return foo(-1);
}
into:
int %_Z4testPN4llvm11InstructionE("struct.llvm::Instruction"* %I) {
entry:
%tmp.1.i.i.i.i.i.i.i = getelementptr "struct.llvm::Instruction"* %I, long 0, ubyte 4 ; <uint*> [#uses=1]
%tmp.2.i.i.i.i.i.i.i = load uint* %tmp.1.i.i.i.i.i.i.i ; <uint> [#uses=2]
%tmp.2.i.i.i.i.i.i = seteq uint %tmp.2.i.i.i.i.i.i.i, 27 ; <bool> [#uses=0]
switch uint %tmp.2.i.i.i.i.i.i.i, label %endif.0 [
uint 27, label %then.0
uint 2, label %then.1
uint 5, label %then.2
uint 14, label %then.3
uint 15, label %then.3
uint 16, label %then.3
uint 17, label %then.3
uint 18, label %then.3
uint 19, label %then.3
uint 32, label %then.4
]
...
As well as handling the cases in 176.gcc and many other programs more effectively.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11964 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 21:28:10 +00:00
Chris Lattner
f2dbf50efa
turn things like:
...
if (X == 0 || X == 2)
...where the comparisons and branches are in different blocks... into a switch
instruction. This comes up a lot in various programs, and works well with
the switch/switch merging code I checked earlier. For example, this testcase:
int switchtest(int C) {
return C == 0 ? f(123) :
C == 1 ? f(3123) :
C == 4 ? f(312) :
C == 5 ? f(1234): f(444);
}
is converted into this:
switch int %C, label %cond_false.3 [
int 0, label %cond_true.0
int 1, label %cond_true.1
int 4, label %cond_true.2
int 5, label %cond_true.3
]
instead of a whole bunch of conditional branches.
Admittedly the code is ugly, and incomplete. To be complete, we need to add
br -> switch merging and switch -> br merging. For example, this testcase:
struct foo { int Q, R, Z; };
#define A (X->Q+X->R * 123)
int test(struct foo *X) {
return A == 123 ? X1() :
A == 12321 ? X2():
(A == 111 || A == 222) ? X3() :
A == 875 ? X4() : X5();
}
Gets compiled to this:
switch int %tmp.7, label %cond_false.2 [
int 123, label %cond_true.0
int 12321, label %cond_true.1
int 111, label %cond_true.2
int 222, label %cond_true.2
]
...
cond_false.2: ; preds = %entry
%tmp.52 = seteq int %tmp.7, 875 ; <bool> [#uses=1]
br bool %tmp.52, label %cond_true.3, label %cond_false.3
where the branch could be folded into the switch.
This kind of thing occurs *ALL OF THE TIME*, especially in programs like
176.gcc, which is a horrible mess of code. It contains stuff like *shudder*:
#define SWITCH_TAKES_ARG(CHAR) \
( (CHAR) == 'D' \
|| (CHAR) == 'U' \
|| (CHAR) == 'o' \
|| (CHAR) == 'e' \
|| (CHAR) == 'u' \
|| (CHAR) == 'I' \
|| (CHAR) == 'm' \
|| (CHAR) == 'L' \
|| (CHAR) == 'A' \
|| (CHAR) == 'h' \
|| (CHAR) == 'z')
and
#define CONST_OK_FOR_LETTER_P(VALUE, C) \
((C) == 'I' ? SMALL_INTVAL (VALUE) \
: (C) == 'J' ? SMALL_INTVAL (-(VALUE)) \
: (C) == 'K' ? (unsigned)(VALUE) < 32 \
: (C) == 'L' ? ((VALUE) & 0xffff) == 0 \
: (C) == 'M' ? integer_ok_for_set (VALUE) \
: (C) == 'N' ? (VALUE) < 0 \
: (C) == 'O' ? (VALUE) == 0 \
: (C) == 'P' ? (VALUE) >= 0 \
: 0)
and
#define LEGITIMIZE_ADDRESS(X,OLDX,MODE,WIN) \
{ \
if (GET_CODE (X) == PLUS && CONSTANT_ADDRESS_P (XEXP (X, 1))) \
(X) = gen_rtx (PLUS, SImode, XEXP (X, 0), \
copy_to_mode_reg (SImode, XEXP (X, 1))); \
if (GET_CODE (X) == PLUS && CONSTANT_ADDRESS_P (XEXP (X, 0))) \
(X) = gen_rtx (PLUS, SImode, XEXP (X, 1), \
copy_to_mode_reg (SImode, XEXP (X, 0))); \
if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 0)) == MULT) \
(X) = gen_rtx (PLUS, SImode, XEXP (X, 1), \
force_operand (XEXP (X, 0), 0)); \
if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 1)) == MULT) \
(X) = gen_rtx (PLUS, SImode, XEXP (X, 0), \
force_operand (XEXP (X, 1), 0)); \
if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 0)) == PLUS) \
(X) = gen_rtx (PLUS, Pmode, force_operand (XEXP (X, 0), NULL_RTX),\
XEXP (X, 1)); \
if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 1)) == PLUS) \
(X) = gen_rtx (PLUS, Pmode, XEXP (X, 0), \
force_operand (XEXP (X, 1), NULL_RTX)); \
if (GET_CODE (X) == SYMBOL_REF || GET_CODE (X) == CONST \
|| GET_CODE (X) == LABEL_REF) \
(X) = legitimize_address (flag_pic, X, 0, 0); \
if (memory_address_p (MODE, X)) \
goto WIN; }
and others. These macros get used multiple times of course. These are such
lovely candidates for macros, aren't they? :)
This code also nicely handles LLVM constructs that look like this:
if (isa<CastInst>(I))
...
else if (isa<BranchInst>(I))
...
else if (isa<SetCondInst>(I))
...
else if (isa<UnwindInst>(I))
...
else if (isa<VAArgInst>(I))
...
where the isa can obviously be a dyn_cast as well. Switch instructions are a
good thing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11870 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-26 07:13:46 +00:00
Chris Lattner
8e509dd5e8
If a block is made dead, make sure to promptly remove it.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11799 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 16:09:21 +00:00
Chris Lattner
d52c261cf8
Implement SimplifyCFG/switch_switch_fold.ll
...
This case occurs many times in various benchmarks, especially when combined
with the previous patch. This allows it to get stuff like:
if (X == 4 || X == 3)
if (X == 5 || X == 8)
and
switch (X) {
case 4: case 5: case 6:
if (X == 4 || X == 5)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11797 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 07:23:58 +00:00
Chris Lattner
e14ea0804a
Rearrange code a bit
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11793 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 05:54:22 +00:00
Chris Lattner
0d56008f53
Implement: test/Regression/Transforms/SimplifyCFG/switch_create.ll
...
This turns code like this:
if (X == 4 | X == 7)
and
if (X != 4 & X != 7)
into switch instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11792 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 05:38:11 +00:00
Chris Lattner
19831ec853
Implement test/Regression/Transforms/SimplifyCFG/UncondBranchToReturn.ll,
...
see the testcase for the reasoning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11496 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-16 06:35:48 +00:00
Chris Lattner
723c66d4c0
Implement SimplifyCFG/PhiEliminate.ll
...
Having a proper 'select' instruction would allow the elimination of a lot
of the special case cruft in this patch, but we don't have one yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11307 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-11 03:36:04 +00:00
Chris Lattner
2355f948c5
The hasConstantReferences predicate always returns false.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11301 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-11 01:17:07 +00:00
Chris Lattner
aeb2a1d708
rename the "exceptional" destination of an invoke instruction to the 'unwind' dest
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11202 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-08 21:44:31 +00:00
Chris Lattner
f7703df496
Finegrainify namespacification
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10727 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-09 06:12:26 +00:00
Brian Gaeke
d0fde30ce8
Put all LLVM code into the llvm namespace, as per bug 109.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9903 91177308-0d34-0410-b5e6-96231b3b80d8
2003-11-11 22:41:34 +00:00
John Criswell
b576c94c15
Added LLVM project notice to the top of every C++ source file.
...
Header files will be on the way.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9298 91177308-0d34-0410-b5e6-96231b3b80d8
2003-10-20 19:43:21 +00:00
Misha Brukman
cf00c4ab3b
Fix spelling.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9027 91177308-0d34-0410-b5e6-96231b3b80d8
2003-10-10 17:57:28 +00:00
Chris Lattner
ee5457cbe8
Eliminate support for the llvm.unwind intrinisic, using the Unwind instruction instead
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8411 91177308-0d34-0410-b5e6-96231b3b80d8
2003-09-08 19:44:26 +00:00
Chris Lattner
dc3602bf0d
Implement SimplifyCFG/InvokeEliminate.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8126 91177308-0d34-0410-b5e6-96231b3b80d8
2003-08-24 18:36:16 +00:00
Chris Lattner
694e37f08a
Fix bug: SimplifyCFG/2003-08-17-BranchFoldOrdering.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7921 91177308-0d34-0410-b5e6-96231b3b80d8
2003-08-17 19:41:53 +00:00
Chris Lattner
122558b05b
Fix bug: SimplifyCFG/2003-08-05-InvokeCrash.ll
...
Fix bug: SimplifyCFG/2003-08-05-MishandleInvoke.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7599 91177308-0d34-0410-b5e6-96231b3b80d8
2003-08-05 16:27:44 +00:00
Chris Lattner
e408e25132
Remove unnecesary &*'s
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5872 91177308-0d34-0410-b5e6-96231b3b80d8
2003-04-23 16:37:45 +00:00
Chris Lattner
3a43837d85
Fix bug: SimplifyCFG/2003-03-07-DominateProblem.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5722 91177308-0d34-0410-b5e6-96231b3b80d8
2003-03-07 18:13:41 +00:00
Chris Lattner
46a5f1f6e4
Implement CFGSimplify/PhiBlockMerge*.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5702 91177308-0d34-0410-b5e6-96231b3b80d8
2003-03-05 21:36:33 +00:00
Chris Lattner
e2ca540e7c
Implement testcase CFGSimplify/EqualPHIEdgeBlockMerge.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5699 91177308-0d34-0410-b5e6-96231b3b80d8
2003-03-05 21:01:52 +00:00
Misha Brukman
a3bbcb5b66
Fix spelling of `propagate'.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4423 91177308-0d34-0410-b5e6-96231b3b80d8
2002-10-29 23:06:16 +00:00
Chris Lattner
bb190ac8da
Changes to support PHINode::removeIncoming changes
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4079 91177308-0d34-0410-b5e6-96231b3b80d8
2002-10-08 21:36:33 +00:00
Chris Lattner
929b2c6900
Fix bug: SimplifyCFG/2002-09-24-PHIAssertion.ll
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3913 91177308-0d34-0410-b5e6-96231b3b80d8
2002-09-24 16:09:17 +00:00
Chris Lattner
3abb95df01
Minor cleanups
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3904 91177308-0d34-0410-b5e6-96231b3b80d8
2002-09-24 00:09:26 +00:00
Chris Lattner
91b65c0b42
Allow folding of basic blocks that have PHI nodes in them, fixing "bug":
...
test/Regression/Transforms/SimplifyCFG/2002-06-24-PHINode.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3128 91177308-0d34-0410-b5e6-96231b3b80d8
2002-07-29 21:26:30 +00:00
Chris Lattner
18961504fc
*** empty log message ***
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2777 91177308-0d34-0410-b5e6-96231b3b80d8
2002-06-25 16:12:52 +00:00
Chris Lattner
01d1ee3a4c
Add implementation of SimplifyCFG
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2701 91177308-0d34-0410-b5e6-96231b3b80d8
2002-05-21 20:50:24 +00:00