1 files changed, 98 insertions, 0 deletions
diff --git a/contrib/llvm/patches/patch-r263312-llvm-r196986-allow-realign-alloca.diff b/contrib/llvm/patches/patch-r263312-llvm-r196986-allow-realign-alloca.diff
new file mode 100644
index 0000000..2c0b759
--- /dev/null
+++ b/contrib/llvm/patches/patch-r263312-llvm-r196986-allow-realign-alloca.diff
@@ -0,0 +1,98 @@
+Pull in r196986 from upstream llvm trunk (by Reid Kleckner):
+
+  Revert the backend fatal error from r196939
+
+  The combination of inline asm, stack realignment, and dynamic allocas
+  turns out to be too common to reject out of hand.
+
+  ASan inserts empy inline asm fragments and uses aligned allocas.
+  Compiling any trivial function containing a dynamic alloca with ASan is
+  enough to trigger the check.
+
+  XFAIL the test cases that would be miscompiled and add one that uses the
+  relevant functionality.
+
+Introduced here: http://svn.freebsd.org/changeset/base/263312
+
+Index: lib/Target/X86/X86RegisterInfo.cpp
+===================================================================
+--- lib/Target/X86/X86RegisterInfo.cpp
++++ lib/Target/X86/X86RegisterInfo.cpp
+@@ -347,12 +347,6 @@ BitVector X86RegisterInfo::getReservedRegs(const M
+         "Stack realignment in presence of dynamic allocas is not supported with"
+         "this calling convention.");
+ 
+-    // FIXME: Do a proper analysis of the inline asm to see if it actually
+-    // conflicts with the base register we chose.
+-    if (MF.hasInlineAsm())
+-      report_fatal_error("Stack realignment in presence of dynamic stack "
+-                         "adjustments is not supported with inline assembly.");
+-
+     for (MCSubRegIterator I(getBaseRegister(), this, /*IncludeSelf=*/true);
+          I.isValid(); ++I)
+       Reserved.set(*I);
+Index: test/CodeGen/X86/inline-asm-stack-realign3.ll
+===================================================================
+--- test/CodeGen/X86/inline-asm-stack-realign3.ll
++++ test/CodeGen/X86/inline-asm-stack-realign3.ll
+@@ -0,0 +1,29 @@
++; RUN: llc -march=x86 < %s | FileCheck %s
++
++declare void @bar(i32* %junk)
++
++define i32 @foo(i1 %cond) {
++entry:
++  %r = alloca i32, align 128
++  store i32 -1, i32* %r, align 128
++  br i1 %cond, label %doit, label %skip
++
++doit:
++  call void asm sideeffect "xor %ecx, %ecx\0A\09mov %ecx, $0", "=*m,~{ecx},~{flags}"(i32* %r)
++  %junk = alloca i32
++  call void @bar(i32* %junk)
++  br label %skip
++
++skip:
++  %0 = load i32* %r, align 128
++  ret i32 %0
++}
++
++; CHECK-LABEL: foo:
++; CHECK: pushl %ebp
++; CHECK: andl $-128, %esp
++; CHECK: xor %ecx, %ecx
++; CHECK-NEXT: mov %ecx, (%esi)
++; CHECK: movl (%esi), %eax
++; CHECK: popl %ebp
++; CHECK: ret
+Index: test/CodeGen/X86/inline-asm-stack-realign.ll
+===================================================================
+--- test/CodeGen/X86/inline-asm-stack-realign.ll
++++ test/CodeGen/X86/inline-asm-stack-realign.ll
+@@ -1,8 +1,8 @@
+ ; RUN: not llc -mtriple=i686-pc-win32 < %s 2>&1 | FileCheck %s
+ 
+-; We don't currently support realigning the stack and adjusting the stack
+-; pointer in inline asm.  This commonly happens in MS inline assembly using
+-; push and pop.
++; FIXME: This is miscompiled due to our unconditional use of ESI as the base
++; pointer.
++; XFAIL:
+ 
+ ; CHECK: Stack realignment in presence of dynamic stack adjustments is not supported with inline assembly
+ 
+Index: test/CodeGen/X86/inline-asm-stack-realign2.ll
+===================================================================
+--- test/CodeGen/X86/inline-asm-stack-realign2.ll
++++ test/CodeGen/X86/inline-asm-stack-realign2.ll
+@@ -1,7 +1,8 @@
+ ; RUN: not llc -mtriple=i686-pc-win32 < %s 2>&1 | FileCheck %s
+ 
+-; We don't currently support realigning the stack and adjusting the stack
+-; pointer in inline asm.  This can even happen in GNU asm.
++; FIXME: This is miscompiled due to our unconditional use of ESI as the base
++; pointer.
++; XFAIL:
+ 
+ ; CHECK: Stack realignment in presence of dynamic stack adjustments is not supported with inline assembly
+