Subzero: Implemented codegen for poisoning and unpoisoning stack redzones

tests_lit/llvm2ice_tests/fused-alloca.ll

 ; This is a basic test of the alloca instruction.
 
 ; RUN: %if --need=target_X8632 --command %p2i --filetype=obj --disassemble \
 ; RUN:   --target x8632 -i %s --args -O2 -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_X8632 --command FileCheck %s
 
 ; Test that a sequence of allocas with less than stack alignment get fused.
 define internal void @fused_small_align(i32 %arg) {
 entry:
   %a1 = alloca i8, i32 8, align 4
   %a2 = alloca i8, i32 12, align 4
   %a3 = alloca i8, i32 16, align 8
   %p1 = bitcast i8* %a1 to i32*
   %p2 = bitcast i8* %a2 to i32*
   %p3 = bitcast i8* %a3 to i32*
   store i32 %arg, i32* %p1, align 1
   store i32 %arg, i32* %p2, align 1
   store i32 %arg, i32* %p3, align 1
   ret void
 }
 ; CHECK-LABEL: fused_small_align
 ; CHECK-NEXT: sub    esp,0x30
 ; CHECK-NEXT: mov    eax,DWORD PTR [esp+0x34]
-; CHECK-NEXT: mov    DWORD PTR [esp+0x1c],eax
 ; CHECK-NEXT: mov    DWORD PTR [esp+0x10],eax
+; CHECK-NEXT: mov    DWORD PTR [esp+0x18],eax
 ; CHECK-NEXT: mov    DWORD PTR [esp],eax
 ; CHECK-NEXT: add    esp,0x30
 
 ; Test that a sequence of allocas with greater than stack alignment get fused.
 define internal void @fused_large_align(i32 %arg) {
 entry:
   %a1 = alloca i8, i32 8, align 32
   %a2 = alloca i8, i32 12, align 64
   %a3 = alloca i8, i32 16, align 32
   %p1 = bitcast i8* %a1 to i32*
   %p2 = bitcast i8* %a2 to i32*
   %p3 = bitcast i8* %a3 to i32*
   store i32 %arg, i32* %p1, align 1
   store i32 %arg, i32* %p2, align 1
   store i32 %arg, i32* %p3, align 1
   ret void
 }
 ; CHECK-LABEL: fused_large_align
 ; CHECK-NEXT: push   ebp
 ; CHECK-NEXT: mov    ebp,esp
 ; CHECK-NEXT: sub    esp,0x80
 ; CHECK-NEXT: and    esp,0xffffffc0
 ; CHECK-NEXT: mov    eax,DWORD PTR [ebp+0x8]
+; CHECK-NEXT: mov    DWORD PTR [esp+0x40],eax
+; CHECK-NEXT: mov    DWORD PTR [esp],eax
 ; CHECK-NEXT: mov    DWORD PTR [esp+0x60],eax
-; CHECK-NEXT: mov    DWORD PTR [esp],eax
-; CHECK-NEXT: mov    DWORD PTR [esp+0x40],eax
 ; CHECK-NEXT: mov    esp,ebp
 ; CHECK-NEXT: pop    ebp
 
 ; Test that an interior pointer into a rematerializable variable is also
 ; rematerializable, and test that it is detected even when the use appears
 ; syntactically before the definition.  Test that it is folded into mem
 ; operands, and also rematerializable through an lea instruction for direct use.
 define internal i32 @fused_derived(i32 %arg) {
 entry:
   %a1 = alloca i8, i32 128, align 4
@@ skipping 85 matching lines @@
 ; CHECK-NEXT: sub    esp,0x24
 ; CHECK-NEXT: mov    eax,DWORD PTR [ebp+0xc]
 ; CHECK-NEXT: and    esp,0xffffffe0
 ; CHECK-NEXT: sub    esp,0x40
 ; CHECK-NEXT: mov    ecx,esp
 ; CHECK-NEXT: mov    edx,ecx
 ; CHECK-NEXT: add    ecx,0x20
 ; CHECK-NEXT: add    edx,0x0
 ; CHECK-NEXT: sub    esp,0x10
 ; CHECK-NEXT: mov    ebx,esp
+; CHECK-NEXT: mov    DWORD PTR [edx],eax
 ; CHECK-NEXT: mov    DWORD PTR [ecx],eax
-; CHECK-NEXT: mov    DWORD PTR [edx],eax
+; CHECK-NEXT: mov    DWORD PTR [ebp-0x14],eax
 ; CHECK-NEXT: mov    DWORD PTR [ebp-0x24],eax
-; CHECK-NEXT: mov    DWORD PTR [ebp-0x14],eax
 ; CHECK-NEXT: mov    DWORD PTR [ebx],eax
 ; CHECK-NEXT: mov    esp,ebp
 ; CHECK-NEXT: pop    ebp