Hal Finkel 6809724935 [InlineAsm] Remove EarlyClobber on registers that are also inputs ... When an inline asm call has an output register marked as early-clobber, but that same register is also an input operand, what should we do? GCC accepts this, and is documented to accept this for read/write operands saying, "Furthermore, if the earlyclobber operand is also a read/write operand, then that operand is written only after it's used." For write-only operands, the situation seems less clear, but I have at least one existing codebase that assumes this will work, in part because it has syscall macros like this: ({ \ register uint64_t r0 __asm__ ("r0") = (__NR_ ## name); \ register uint64_t r3 __asm__ ("r3") = ((uint64_t) (arg0)); \ register uint64_t r4 __asm__ ("r4") = ((uint64_t) (arg1)); \ register uint64_t r5 __asm__ ("r5") = ((uint64_t) (arg2)); \ __asm__ __volatile__ \ ("sc" \ : "=&r"(r0),"=&r"(r3),"=&r"(r4),"=&r"(r5) \ : "0"(r0), "1"(r3), "2"(r4), "3"(r5) \ : "r6","r7","r8","r9","r10","r11","r12","cr0","memory"); \ r3; \ }) Furthermore, with register aliases and subregister relationships that only the backend knows about, rejecting this in the frontend seems like a difficult proposition (if we wanted to do so). However, keeping the early-clobber flag on the INLINEASM MI does not work for us, because it will cause the register's live interval to end to soon (so it will not appear defined to be used as an input). Fortunately, fixing this does not seem hard: When forming the INLINEASM MI, check to see if any of the early-clobber outputs are also inputs, and if so, remove the early-clobber flag. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235283 91177308-0d34-0410-b5e6-96231b3b80d8		2015-04-20 00:01:30 +00:00
..
Analysis	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
Assembler	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
Bindings
Bitcode	[opaque pointer type] Explicit pointee type for call instruction	2015-04-17 06:40:14 +00:00
BugPoint
CodeGen	[InlineAsm] Remove EarlyClobber on registers that are also inputs	2015-04-20 00:01:30 +00:00
DebugInfo	DebugInfo: Fixup r235149 after IR change in r235145	2015-04-17 00:37:53 +00:00
ExecutionEngine	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
Feature	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
FileCheck
Instrumentation	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
Integer	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
JitListener
Linker	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
LTO	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
MC	Compute A-B when A or B is weak.	2015-04-17 21:15:17 +00:00
Object
Other	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
SymbolRewriter
TableGen	Add support for v1i128 type.	2015-04-17 16:11:05 +00:00
tools
Transforms	[MemCpyOpt] Don't force i64 when promoting memset/memcpy sizes.	2015-04-18 23:06:04 +00:00
Unit
Verifier	[opaque pointer type] Add textual IR support for explicit type parameter to the call instruction	2015-04-16 23:24:18 +00:00
YAMLParser
.clang-format
CMakeLists.txt
lit.cfg
lit.site.cfg.in
Makefile
Makefile.tests
TestRunner.sh