Here is a theoretical example that illustrates why the placement is important.
tmp1 =
store tmp1 -> x
...
tmp2 = add ...
...
call
...
store tmp2 -> x
Now mem2reg comes along:
tmp1 =
dbg_value (tmp1 -> x)
...
tmp2 = add ...
...
call
...
dbg_value (tmp2 -> x)
When the debugger examine the value of x after the add instruction but before the call, it should have the value of tmp1.
Furthermore, for dbg_value's that reference constants, they should not be emitted at the beginning of the block (since they do not have "producers").
This patch also cleans up how SDISel manages DbgValue nodes. It allow a SDNode to be referenced by multiple SDDbgValue nodes. When a SDNode is deleted, it uses the information to find the SDDbgValues and invalidate them. They are not deleted until the corresponding SelectionDAG is destroyed.
llvm-svn: 99469
--- Reverse-merging r99440 into '.':
U test/MC/AsmParser/X86/x86_32-bit_cat.s
U test/MC/AsmParser/X86/x86_32-encoding.s
U include/llvm/IntrinsicsX86.td
U include/llvm/CodeGen/SelectionDAGNodes.h
U lib/Target/X86/X86InstrSSE.td
U lib/Target/X86/X86ISelLowering.h
llvm-svn: 99450
I have audited all getOperandNo calls now, fixing
hidden assumptions. CallSite related uglyness will
be eliminated successively.
Note this patch has a long and griveous history,
for all the back-and-forths have a look at
CallSite.h's log.
llvm-svn: 99399
for the noinline attribute, and make the inliner refuse to
inline a call site when the call site is marked noinline even
if the callee isn't. This fixes PR6682.
llvm-svn: 99341
so that the SCEVExpander doesn't retain a dangling pointer as its
insert position. The dangling pointer in this case wasn't ever used
to insert new instructions, but it was causing trouble with
SCEVExpander's code for automatically advancing its insert position
past debug intrinsics.
This fixes use-after-free errors that valgrind noticed in
test/Transforms/IndVarSimplify/2007-06-06-DeleteDanglesPtr.ll and
test/Transforms/IndVarSimplify/exit_value_tests.ll.
llvm-svn: 99036
use-before-def errors in SCEVExpander-produced code in sqlite3 when debug
info with optimization is enabled, though the testcases for this are
dependent on use-list order.
llvm-svn: 99001
override prefix and only the r/m16 forms should have had that. Also for variant
one, the AT&T syntax, added suffixes to all forms. Also added the missing
64-bit form for 'CRC32 r64, r/m8'. Plus added test cases for all forms and
tweaked one test case to add the needed suffixes.
llvm-svn: 98980
disabled for several months (since svn r88806) and no one noticed. My fix
for pr6543 yesterday reenabled it, but broke the ARM port's code for using
TBB/TBH. Rather than adding a target hook to disable merging for Thumb2 only,
I'm just taking this out. It is not common to have identical jump tables,
the code we used to merge them was O(N^2), and it only helps code size, not
performance.
llvm-svn: 98977
This time I did a self-hosted bootstrap on Linux x86-64,
with no problems. Let's see how darwin 64-bit self-hosting
goes. At the first sign of failure I'll back this out.
Maybe the valgrind bots give me a hint of what may be wrong
(it at all).
llvm-svn: 98957