From: Steve MacLean <sdmaclea@qti.qualcomm.com>
Date: Wed, 1 Mar 2017 22:16:23 +0000 (-0500)
Subject: [Arm64/Unix] Fix stack unwinding (dotnet/coreclr#9877)
X-Git-Tag: submit/tizen/20210909.063632~11030^2~7893
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=264c405cbfcefcebb39298fcb8e9c9486a1e92d6;p=platform%2Fupstream%2Fdotnet%2Fruntime.git

[Arm64/Unix] Fix stack unwinding (dotnet/coreclr#9877)

This restore the functionality lost by dotnet/coreclr#9866 w/o functional
loss

Commit migrated from https://github.com/dotnet/coreclr/commit/7b8f9d6c8f5b196b8cf7da6f4c49bf4149f3e15a
---

diff --git a/src/coreclr/src/pal/inc/unixasmmacrosarm64.inc b/src/coreclr/src/pal/inc/unixasmmacrosarm64.inc
index ed73748..f0c4a5e 100644
--- a/src/coreclr/src/pal/inc/unixasmmacrosarm64.inc
+++ b/src/coreclr/src/pal/inc/unixasmmacrosarm64.inc
@@ -43,7 +43,6 @@ C_FUNC(\Name\()_End):
 
 .macro PROLOG_STACK_ALLOC Size
         sub sp, sp, \Size
-        .cfi_adjust_cfa_offset \Size
 .endm
 
 .macro EPILOG_STACK_FREE Size
@@ -67,6 +66,7 @@ C_FUNC(\Name\()_End):
         .cfi_rel_offset \reg2, \ofs + 8
         .ifc \reg1, fp
         mov fp, sp
+        .cfi_def_cfa_register fp
         .endif
 .endm
 
@@ -77,6 +77,7 @@ C_FUNC(\Name\()_End):
         .cfi_rel_offset \reg2, 8
         .ifc \reg1, fp
         mov fp, sp
+        .cfi_def_cfa_register fp
         .endif
 .endm
 
@@ -191,19 +192,10 @@ C_FUNC(\Name\()_End):
 .macro SAVE_ARGUMENT_REGISTERS reg, ofs
 
         stp                    x0, x1, [\reg, #(\ofs)]
-       .cfi_rel_offset x0, \ofs
-       .cfi_rel_offset x1, \ofs + 8
         stp                    x2, x3, [\reg, #(\ofs + 16)]
-       .cfi_rel_offset x2, \ofs + 16
-       .cfi_rel_offset x3, \ofs + 24
         stp                    x4, x5, [\reg, #(\ofs + 32)]
-       .cfi_rel_offset x4, \ofs + 32
-       .cfi_rel_offset x5, \ofs + 40
         stp                    x6, x7, [\reg, #(\ofs + 48)]
-       .cfi_rel_offset x6, \ofs + 48
-       .cfi_rel_offset x7, \ofs + 56
         str                    x8, [\reg, #(\ofs + 64)]
-       .cfi_rel_offset x8, \ofs + 64
 
 .endm
 
@@ -211,53 +203,28 @@ C_FUNC(\Name\()_End):
 .macro SAVE_FLOAT_ARGUMENT_REGISTERS reg, ofs
 
         stp                    d0, d1, [\reg, #(\ofs)]
-       .cfi_rel_offset d0, \ofs + 0
-       .cfi_rel_offset d1, \ofs + 8
         stp                    d2, d3, [\reg, #(\ofs + 16)]
-       .cfi_rel_offset d2, \ofs + 16
-       .cfi_rel_offset d3, \ofs + 24
         stp                    d4, d5, [\reg, #(\ofs + 32)]
-       .cfi_rel_offset d4, \ofs + 32
-       .cfi_rel_offset d5, \ofs + 40
         stp                    d6, d7, [\reg, #(\ofs + 48)]
-       .cfi_rel_offset d6, \ofs + 48
-       .cfi_rel_offset d7, \ofs + 56
 
 .endm
 
 .macro RESTORE_ARGUMENT_REGISTERS reg, ofs
 
         ldp                    x0, x1, [\reg, #(\ofs)]
-        .cfi_restore x0
-        .cfi_restore x1
         ldp                    x2, x3, [\reg, #(\ofs + 16)]
-        .cfi_restore x2
-        .cfi_restore x3
         ldp                    x4, x5, [\reg, #(\ofs + 32)]
-        .cfi_restore x4
-        .cfi_restore x5
         ldp                    x6, x7, [\reg, #(\ofs + 48)]
-        .cfi_restore x6
-        .cfi_restore x7
         ldr                    x8, [\reg, #(\ofs + 64)]
-        .cfi_restore x8
 
 .endm
 
 .macro RESTORE_FLOAT_ARGUMENT_REGISTERS reg, ofs
 
         ldp                    d0, d1, [\reg, #(\ofs)]
-        .cfi_restore d0
-        .cfi_restore d1
         ldp                    d2, d3, [\reg, #(\ofs + 16)]
-        .cfi_restore d2
-        .cfi_restore d3
         ldp                    d4, d5, [\reg, #(\ofs + 32)]
-        .cfi_restore d4
-        .cfi_restore d5
         ldp                    d6, d7, [\reg, #(\ofs + 48)]
-        .cfi_restore d6
-        .cfi_restore d7
 
 .endm
 
diff --git a/src/coreclr/src/pal/src/arch/arm64/callsignalhandlerwrapper.S b/src/coreclr/src/pal/src/arch/arm64/callsignalhandlerwrapper.S
index 48b2596..90fb602 100644
--- a/src/coreclr/src/pal/src/arch/arm64/callsignalhandlerwrapper.S
+++ b/src/coreclr/src/pal/src/arch/arm64/callsignalhandlerwrapper.S
@@ -17,6 +17,7 @@ C_FUNC(SignalHandlerWorkerReturnOffset\Alignment):
 NESTED_ENTRY CallSignalHandlerWrapper\Alignment, _TEXT, NoHandler
 __StackAllocationSize = (128 + 8 + 8 + \Alignment) // red zone + fp + lr + alignment 
     PROLOG_STACK_ALLOC __StackAllocationSize
+    .cfi_adjust_cfa_offset __StackAllocationSize
     PROLOG_SAVE_REG_PAIR fp, lr, 0
     bl      EXTERNAL_C_FUNC(signal_handler_worker)
 LOCAL_LABEL(SignalHandlerWorkerReturn\Alignment):
diff --git a/src/coreclr/src/vm/arm64/asmhelpers.S b/src/coreclr/src/vm/arm64/asmhelpers.S
index b318ad9..ef6b5cf 100644
--- a/src/coreclr/src/vm/arm64/asmhelpers.S
+++ b/src/coreclr/src/vm/arm64/asmhelpers.S
@@ -909,7 +909,13 @@ NESTED_ENTRY CallEHFunclet, _TEXT, NoHandler
     // X3 = address of the location where the SP of funclet's caller (i.e. this helper) should be saved.
     //
 
-    PROLOG_SAVE_REG_PAIR_INDEXED   fp, lr, -96
+    // Using below prolog instead of PROLOG_SAVE_REG_PAIR_INDEXED fp,lr, -96
+    // is intentional. Above statement would also emit instruction to save
+    // sp in fp. If sp is saved in fp in prolog then it is not expected that fp can change in the body
+    // of method. However, this method needs to be able to change fp before calling funclet.
+    // This is required to access locals in funclet.
+    PROLOG_SAVE_REG_PAIR_INDEXED   x29, lr, -96
+
     // Spill callee saved registers
     PROLOG_SAVE_REG_PAIR   x19, x20, 16
     PROLOG_SAVE_REG_PAIR   x21, x22, 32