From 22c328969db7f50ab4378362eec797662e88450f Mon Sep 17 00:00:00 2001 From: Petar Jovanovic Date: Thu, 7 Feb 2019 22:57:33 +0000 Subject: [PATCH] [mips][micromips] Fix how values in .gcc_except_table are calculated When a landing pad is calculated in a program that is compiled for micromips with -fPIC flag, it will point to an even address. Such an error will cause a segmentation fault, as the instructions in micromips are aligned on odd addresses. This patch sets the last bit of the offset where a landing pad is, to 1, which will effectively be an odd address and point to the instruction exactly. r344591 fixed this issue for -static compilation. Patch by Aleksandar Beserminji. Differential Revision: https://reviews.llvm.org/D57677 llvm-svn: 353480 --- lib/MC/MCExpr.cpp | 5 +++++ test/CodeGen/Mips/micromips-b-range.ll | 8 ++++---- test/DebugInfo/Mips/eh_frame.ll | 22 +++++++++++++++++----- 3 files changed, 26 insertions(+), 9 deletions(-) diff --git a/lib/MC/MCExpr.cpp b/lib/MC/MCExpr.cpp index d8091e41f1a..7ca935f248d 100644 --- a/lib/MC/MCExpr.cpp +++ b/lib/MC/MCExpr.cpp @@ -558,6 +558,11 @@ static void AttemptToFoldSymbolOffsetDifference( if (Asm->isThumbFunc(&SA)) Addend |= 1; + // If symbol is labeled as micromips, we set low-bit to ensure + // correct offset in .gcc_except_table + if (Asm->getBackend().isMicroMips(&SA)) + Addend |= 1; + // Clear the symbol expr pointers to indicate we have folded these // operands. A = B = nullptr; diff --git a/test/CodeGen/Mips/micromips-b-range.ll b/test/CodeGen/Mips/micromips-b-range.ll index 5831ae81bae..27a0db545f7 100644 --- a/test/CodeGen/Mips/micromips-b-range.ll +++ b/test/CodeGen/Mips/micromips-b-range.ll @@ -13,7 +13,7 @@ ; CHECK-NEXT: 1e: fb fd 00 00 sw $ra, 0($sp) ; CHECK-NEXT: 22: 41 a1 00 01 lui $1, 1 ; CHECK-NEXT: 26: 40 60 00 02 bal 8 -; CHECK-NEXT: 2a: 30 21 04 68 addiu $1, $1, 1128 +; CHECK-NEXT: 2a: 30 21 04 69 addiu $1, $1, 1129 ; CHECK-NEXT: 2e: 00 3f 09 50 addu $1, $ra, $1 ; CHECK-NEXT: 32: ff fd 00 00 lw $ra, 0($sp) ; CHECK-NEXT: 36: 00 01 0f 3c jr $1 @@ -27,7 +27,7 @@ ; CHECK-NEXT: 56: fb fd 00 00 sw $ra, 0($sp) ; CHECK-NEXT: 5a: 41 a1 00 01 lui $1, 1 ; CHECK-NEXT: 5e: 40 60 00 02 bal 8 -; CHECK-NEXT: 62: 30 21 04 5c addiu $1, $1, 1116 +; CHECK-NEXT: 62: 30 21 04 5d addiu $1, $1, 1117 ; CHECK-NEXT: 66: 00 3f 09 50 addu $1, $ra, $1 ; CHECK-NEXT: 6a: ff fd 00 00 lw $ra, 0($sp) ; CHECK-NEXT: 6e: 00 01 0f 3c jr $1 @@ -39,7 +39,7 @@ ; CHECK-NEXT: 86: fb fd 00 00 sw $ra, 0($sp) ; CHECK-NEXT: 8a: 41 a1 00 01 lui $1, 1 ; CHECK-NEXT: 8e: 40 60 00 02 bal 8 -; CHECK-NEXT: 92: 30 21 04 2c addiu $1, $1, 1068 +; CHECK-NEXT: 92: 30 21 04 2d addiu $1, $1, 1069 ; CHECK-NEXT: 96: 00 3f 09 50 addu $1, $ra, $1 ; CHECK-NEXT: 9a: ff fd 00 00 lw $ra, 0($sp) ; CHECK-NEXT: 9e: 00 01 0f 3c jr $1 @@ -51,7 +51,7 @@ ; CHECK-NEXT: 10476: fb fd 00 00 sw $ra, 0($sp) ; CHECK-NEXT: 1047a: 41 a1 00 01 lui $1, 1 ; CHECK-NEXT: 1047e: 40 60 00 02 bal 8 -; CHECK-NEXT: 10482: 30 21 04 00 addiu $1, $1, 1024 +; CHECK-NEXT: 10482: 30 21 04 01 addiu $1, $1, 1025 ; CHECK-NEXT: 10486: 00 3f 09 50 addu $1, $ra, $1 ; CHECK-NEXT: 1048a: ff fd 00 00 lw $ra, 0($sp) ; CHECK-NEXT: 1048e: 00 01 0f 3c jr $1 diff --git a/test/DebugInfo/Mips/eh_frame.ll b/test/DebugInfo/Mips/eh_frame.ll index 4687443cb1c..122d0a7f6ab 100644 --- a/test/DebugInfo/Mips/eh_frame.ll +++ b/test/DebugInfo/Mips/eh_frame.ll @@ -1,9 +1,21 @@ -; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -O3 -filetype=obj -o - %s | llvm-readelf -r | FileCheck %s +; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=static -O3 -filetype=obj -o - %s | \ +; RUN: llvm-readelf -r | FileCheck %s --check-prefix=CHECK-READELF +; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=pic -O3 -filetype=obj -o - %s | \ +; RUN: llvm-readelf -r | FileCheck %s --check-prefix=CHECK-READELF +; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=static -O3 -filetype=obj -o - %s | \ +; RUN: llvm-objdump -s -j .gcc_except_table - | FileCheck %s --check-prefix=CHECK-EXCEPT-TABLE-STATIC +; RUN: llc -mtriple mips-unknown-linux-gnu -mattr=+micromips -relocation-model=pic -O3 -filetype=obj -o - %s | \ +; RUN: llvm-objdump -s -j .gcc_except_table - | FileCheck %s --check-prefix=CHECK-EXCEPT-TABLE-PIC -; CHECK: .rel.eh_frame -; CHECK: DW.ref.__gxx_personality_v0 -; CHECK-NEXT: .text -; CHECK-NEXT: .gcc_except_table +; CHECK-READELF: .rel.eh_frame +; CHECK-READELF: DW.ref.__gxx_personality_v0 +; CHECK-READELF-NEXT: .text +; CHECK-READELF-NEXT: .gcc_except_table + +; CHECK-EXCEPT-TABLE-STATIC: 0000 ff9b1501 0c011500 00150e23 01231e00 ...........#.#.. +; CHECK-EXCEPT-TABLE-STATIC: 0010 00010000 00000000 +; CHECK-EXCEPT-TABLE-PIC: 0000 ff9b1501 0c012d00 002d133f 013f2a00 ......-..-.?.?*. +; CHECK-EXCEPT-TABLE-PIC: 0010 00010000 00000000 ........ @_ZTIi = external constant i8*