Fix nasty mingw32 bug, which e.g. prevented llvm-gcc bootstrap there.
Mark _alloca call as clobberring EFLAGS, otherwise some DCE might remove
other flags-clobberring stuff (e.g. cmp instructions) occuring after
_alloca call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112034 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 7adaf97..dc1bab3 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -8930,7 +8930,8 @@
.addReg(X86::EAX, RegState::Implicit)
.addReg(X86::ESP, RegState::Implicit)
.addReg(X86::EAX, RegState::Define | RegState::Implicit)
- .addReg(X86::ESP, RegState::Define | RegState::Implicit);
+ .addReg(X86::ESP, RegState::Define | RegState::Implicit)
+ .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
MI->eraseFromParent(); // The pseudo instruction is gone now.
return BB;
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 60af8ed..84fde71 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -580,9 +580,10 @@
// The main point of having separate instruction are extra unmodelled effects
// (compared to ordinary calls) like stack pointer change.
-def MINGW_ALLOCA : I<0, Pseudo, (outs), (ins),
- "# dynamic stack allocation",
- [(X86MingwAlloca)]>;
+let Defs = [EAX, ESP, EFLAGS], Uses = [ESP] in
+ def MINGW_ALLOCA : I<0, Pseudo, (outs), (ins),
+ "# dynamic stack allocation",
+ [(X86MingwAlloca)]>;
}
// Nop
diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp
index 746e3fa..56ddfb0 100644
--- a/lib/Target/X86/X86RegisterInfo.cpp
+++ b/lib/Target/X86/X86RegisterInfo.cpp
@@ -1109,7 +1109,8 @@
.addImm(NumBytes);
BuildMI(MBB, MBBI, DL, TII.get(X86::CALLpcrel32))
.addExternalSymbol("_alloca")
- .addReg(StackPtr, RegState::Define | RegState::Implicit);
+ .addReg(StackPtr, RegState::Define | RegState::Implicit)
+ .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
} else {
// Save EAX
BuildMI(MBB, MBBI, DL, TII.get(X86::PUSH32r))
@@ -1121,7 +1122,8 @@
.addImm(NumBytes - 4);
BuildMI(MBB, MBBI, DL, TII.get(X86::CALLpcrel32))
.addExternalSymbol("_alloca")
- .addReg(StackPtr, RegState::Define | RegState::Implicit);
+ .addReg(StackPtr, RegState::Define | RegState::Implicit)
+ .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
// Restore EAX
MachineInstr *MI = addRegOffset(BuildMI(MF, DL, TII.get(X86::MOV32rm),