llvm-6502/include/llvm/CodeGen/RuntimeLibcalls.h
Duncan Sands b0f1e1780c Add a new codegen pass that normalizes dwarf exception handling
code in preparation for code generation.  The main thing it does
is handle the case when eh.exception calls (and, in a future
patch, eh.selector calls) are far away from landing pads.  Right
now in practice you only find eh.exception calls close to landing
pads: either in a landing pad (the common case) or in a landing
pad successor, due to loop passes shifting them about.  However
future exception handling improvements will result in calls far
from landing pads:
(1) Inlining of rewinds.  Consider the following case:
In function @f:
...
  invoke @g to label %normal unwind label %unwinds
...
unwinds:
  %ex = call i8* @llvm.eh.exception()
...

In function @g:
...
  invoke @something to label %continue unwind label %handler
...
handler:
  %ex = call i8* @llvm.eh.exception()
... perform cleanups ...
  "rethrow exception"

Now inline @g into @f.  Currently this is turned into:
In function @f:
...
  invoke @something to label %continue unwind label %handler
...
handler:
  %ex = call i8* @llvm.eh.exception()
... perform cleanups ...
  invoke "rethrow exception" to label %normal unwind label %unwinds
unwinds:
  %ex = call i8* @llvm.eh.exception()
...

However we would like to simplify invoke of "rethrow exception" into
a branch to the %unwinds label.  Then %unwinds is no longer a landing
pad, and the eh.exception call there is then far away from any landing
pads.

(2) Using the unwind instruction for cleanups.
It would be nice to have codegen handle the following case:
  invoke @something to label %continue unwind label %run_cleanups
...
handler:
... perform cleanups ...
  unwind

This requires turning "unwind" into a library call, which
necessarily takes a pointer to the exception as an argument
(this patch also does this unwind lowering).  But that means
you are using eh.exception again far from a landing pad.

(3) Bugpoint simplifications.  When bugpoint is simplifying
exception handling code it often generates eh.exception calls
far from a landing pad, which then causes codegen to assert.
Bugpoint then latches on to this assertion and loses sight
of the original problem.

Note that it is currently rare for this pass to actually do
anything.  And in fact it normally shouldn't do anything at
all given the code coming out of llvm-gcc!  But it does fire
a few times in the testsuite.  As far as I can see this is
almost always due to the LoopStrengthReduce codegen pass
introducing pointless loop preheader blocks which are landing
pads and only contain a branch to another block.  This other
block contains an eh.exception call.  So probably by tweaking
LoopStrengthReduce a bit this can be avoided.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72276 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-22 20:36:31 +00:00

256 lines
5.3 KiB
C++

//===-- CodeGen/RuntimeLibcall.h - Runtime Library Calls --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the enum representing the list of runtime library calls
// the backend may emit during code generation, and also some helper functions.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_RUNTIMELIBCALLS_H
#define LLVM_CODEGEN_RUNTIMELIBCALLS_H
#include "llvm/CodeGen/ValueTypes.h"
namespace llvm {
namespace RTLIB {
/// RTLIB::Libcall enum - This enum defines all of the runtime library calls
/// the backend can emit. The various long double types cannot be merged,
/// because 80-bit library functions use "xf" and 128-bit use "tf".
///
/// When adding PPCF128 functions here, note that their names generally need
/// to be overridden for Darwin with the xxx$LDBL128 form. See
/// PPCISelLowering.cpp.
///
enum Libcall {
// Integer
SHL_I16,
SHL_I32,
SHL_I64,
SHL_I128,
SRL_I16,
SRL_I32,
SRL_I64,
SRL_I128,
SRA_I16,
SRA_I32,
SRA_I64,
SRA_I128,
MUL_I16,
MUL_I32,
MUL_I64,
MUL_I128,
SDIV_I16,
SDIV_I32,
SDIV_I64,
SDIV_I128,
UDIV_I16,
UDIV_I32,
UDIV_I64,
UDIV_I128,
SREM_I16,
SREM_I32,
SREM_I64,
SREM_I128,
UREM_I16,
UREM_I32,
UREM_I64,
UREM_I128,
NEG_I32,
NEG_I64,
// FLOATING POINT
ADD_F32,
ADD_F64,
ADD_F80,
ADD_PPCF128,
SUB_F32,
SUB_F64,
SUB_F80,
SUB_PPCF128,
MUL_F32,
MUL_F64,
MUL_F80,
MUL_PPCF128,
DIV_F32,
DIV_F64,
DIV_F80,
DIV_PPCF128,
REM_F32,
REM_F64,
REM_F80,
REM_PPCF128,
POWI_F32,
POWI_F64,
POWI_F80,
POWI_PPCF128,
SQRT_F32,
SQRT_F64,
SQRT_F80,
SQRT_PPCF128,
LOG_F32,
LOG_F64,
LOG_F80,
LOG_PPCF128,
LOG2_F32,
LOG2_F64,
LOG2_F80,
LOG2_PPCF128,
LOG10_F32,
LOG10_F64,
LOG10_F80,
LOG10_PPCF128,
EXP_F32,
EXP_F64,
EXP_F80,
EXP_PPCF128,
EXP2_F32,
EXP2_F64,
EXP2_F80,
EXP2_PPCF128,
SIN_F32,
SIN_F64,
SIN_F80,
SIN_PPCF128,
COS_F32,
COS_F64,
COS_F80,
COS_PPCF128,
POW_F32,
POW_F64,
POW_F80,
POW_PPCF128,
CEIL_F32,
CEIL_F64,
CEIL_F80,
CEIL_PPCF128,
TRUNC_F32,
TRUNC_F64,
TRUNC_F80,
TRUNC_PPCF128,
RINT_F32,
RINT_F64,
RINT_F80,
RINT_PPCF128,
NEARBYINT_F32,
NEARBYINT_F64,
NEARBYINT_F80,
NEARBYINT_PPCF128,
FLOOR_F32,
FLOOR_F64,
FLOOR_F80,
FLOOR_PPCF128,
// CONVERSION
FPEXT_F32_F64,
FPROUND_F64_F32,
FPROUND_F80_F32,
FPROUND_PPCF128_F32,
FPROUND_F80_F64,
FPROUND_PPCF128_F64,
FPTOSINT_F32_I32,
FPTOSINT_F32_I64,
FPTOSINT_F32_I128,
FPTOSINT_F64_I32,
FPTOSINT_F64_I64,
FPTOSINT_F64_I128,
FPTOSINT_F80_I32,
FPTOSINT_F80_I64,
FPTOSINT_F80_I128,
FPTOSINT_PPCF128_I32,
FPTOSINT_PPCF128_I64,
FPTOSINT_PPCF128_I128,
FPTOUINT_F32_I32,
FPTOUINT_F32_I64,
FPTOUINT_F32_I128,
FPTOUINT_F64_I32,
FPTOUINT_F64_I64,
FPTOUINT_F64_I128,
FPTOUINT_F80_I32,
FPTOUINT_F80_I64,
FPTOUINT_F80_I128,
FPTOUINT_PPCF128_I32,
FPTOUINT_PPCF128_I64,
FPTOUINT_PPCF128_I128,
SINTTOFP_I32_F32,
SINTTOFP_I32_F64,
SINTTOFP_I32_F80,
SINTTOFP_I32_PPCF128,
SINTTOFP_I64_F32,
SINTTOFP_I64_F64,
SINTTOFP_I64_F80,
SINTTOFP_I64_PPCF128,
SINTTOFP_I128_F32,
SINTTOFP_I128_F64,
SINTTOFP_I128_F80,
SINTTOFP_I128_PPCF128,
UINTTOFP_I32_F32,
UINTTOFP_I32_F64,
UINTTOFP_I32_F80,
UINTTOFP_I32_PPCF128,
UINTTOFP_I64_F32,
UINTTOFP_I64_F64,
UINTTOFP_I64_F80,
UINTTOFP_I64_PPCF128,
UINTTOFP_I128_F32,
UINTTOFP_I128_F64,
UINTTOFP_I128_F80,
UINTTOFP_I128_PPCF128,
// COMPARISON
OEQ_F32,
OEQ_F64,
UNE_F32,
UNE_F64,
OGE_F32,
OGE_F64,
OLT_F32,
OLT_F64,
OLE_F32,
OLE_F64,
OGT_F32,
OGT_F64,
UO_F32,
UO_F64,
O_F32,
O_F64,
// EXCEPTION HANDLING
UNWIND_RESUME,
UNKNOWN_LIBCALL
};
/// getFPEXT - Return the FPEXT_*_* value for the given types, or
/// UNKNOWN_LIBCALL if there is none.
Libcall getFPEXT(MVT OpVT, MVT RetVT);
/// getFPROUND - Return the FPROUND_*_* value for the given types, or
/// UNKNOWN_LIBCALL if there is none.
Libcall getFPROUND(MVT OpVT, MVT RetVT);
/// getFPTOSINT - Return the FPTOSINT_*_* value for the given types, or
/// UNKNOWN_LIBCALL if there is none.
Libcall getFPTOSINT(MVT OpVT, MVT RetVT);
/// getFPTOUINT - Return the FPTOUINT_*_* value for the given types, or
/// UNKNOWN_LIBCALL if there is none.
Libcall getFPTOUINT(MVT OpVT, MVT RetVT);
/// getSINTTOFP - Return the SINTTOFP_*_* value for the given types, or
/// UNKNOWN_LIBCALL if there is none.
Libcall getSINTTOFP(MVT OpVT, MVT RetVT);
/// getUINTTOFP - Return the UINTTOFP_*_* value for the given types, or
/// UNKNOWN_LIBCALL if there is none.
Libcall getUINTTOFP(MVT OpVT, MVT RetVT);
}
}
#endif