On x86-64, for a varargs function, don't store the xmm registers to
the register save area if %al is 0. This avoids touching xmm
regsiters when they aren't actually used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79061 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index ecb1b20..f131026 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -56,6 +56,10 @@
def SDT_X86Call : SDTypeProfile<0, -1, [SDTCisVT<0, iPTR>]>;
+def SDT_X86VASTART_SAVE_XMM_REGS : SDTypeProfile<0, -1, [SDTCisVT<0, i8>,
+ SDTCisVT<1, iPTR>,
+ SDTCisVT<2, iPTR>]>;
+
def SDTX86RepStr : SDTypeProfile<0, 1, [SDTCisVT<0, OtherVT>]>;
def SDTX86RdTsc : SDTypeProfile<0, 0, []>;
@@ -114,6 +118,11 @@
def X86retflag : SDNode<"X86ISD::RET_FLAG", SDTX86Ret,
[SDNPHasChain, SDNPOptInFlag]>;
+def X86vastart_save_xmm_regs :
+ SDNode<"X86ISD::VASTART_SAVE_XMM_REGS",
+ SDT_X86VASTART_SAVE_XMM_REGS,
+ [SDNPHasChain]>;
+
def X86callseq_start :
SDNode<"ISD::CALLSEQ_START", SDT_X86CallSeqStart,
[SDNPHasChain, SDNPOutFlag]>;
@@ -511,6 +520,18 @@
Requires<[In32BitMode]>;
}
+// x86-64 va_start lowering magic.
+let usesCustomDAGSchedInserter = 1 in
+def VASTART_SAVE_XMM_REGS : I<0, Pseudo,
+ (outs),
+ (ins GR8:$al,
+ i64imm:$regsavefi, i64imm:$offset,
+ variable_ops),
+ "#VASTART_SAVE_XMM_REGS $al, $regsavefi, $offset",
+ [(X86vastart_save_xmm_regs GR8:$al,
+ imm:$regsavefi,
+ imm:$offset)]>;
+
// Nop
let neverHasSideEffects = 1 in {
def NOOP : I<0x90, RawFrm, (outs), (ins), "nop", []>;