cl::desc("Maximum number of prefixes to use for padding"));
cl::opt<bool> X86PadForAlign(
- "x86-pad-for-align", cl::init(true), cl::Hidden,
+ "x86-pad-for-align", cl::init(false), cl::Hidden,
cl::desc("Pad previous instructions to implement align directives"));
cl::opt<bool> X86PadForBranchAlign(
if (!X86PadForAlign && !X86PadForBranchAlign)
return;
+ // The processed regions are delimitered by LabeledFragments. -g may have more
+ // MCSymbols and therefore different relaxation results. X86PadForAlign is
+ // disabled by default to eliminate the -g vs non -g difference.
DenseSet<MCFragment *> LabeledFragments;
for (const MCSymbol &S : Asm.symbols())
LabeledFragments.insert(S.getFragment(false));
- # RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=5 | llvm-objdump -d - | FileCheck %s
+ # RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=5 -x86-pad-for-align=1 | llvm-objdump -d - | FileCheck %s
# The first test check the correctness cornercase - can't add prefixes on a
-# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=5 | llvm-objdump -d --section=.text - | FileCheck %s
+# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=5 -x86-pad-for-align=1 | llvm-objdump -d - | FileCheck %s
# This test file highlights the interactions between prefix padding and
# relaxation padding.
-# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu -x86-pad-max-prefix-size=0 %s | llvm-objdump -d --section=.text - | FileCheck %s
+# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu -x86-pad-max-prefix-size=0 %s | llvm-objdump -d - | FileCheck %s --check-prefix=NOPAD
+# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu -x86-pad-max-prefix-size=0 -x86-pad-for-align=1 %s | llvm-objdump -d - | FileCheck %s
# This test exercises only the padding via relaxation logic. The interaction
# etween prefix padding and relaxation logic can be seen in align-via-padding.s
.file "test.c"
.text
.section .text
+
+# NOPAD-LABEL: <.text>:
+# NOPAD-NEXT: 0: eb 1f jmp 0x21 <foo>
+# NOPAD-NEXT: 2: eb 1d jmp 0x21 <foo>
+# NOPAD-NEXT: 4: eb 1b jmp 0x21 <foo>
+# NOPAD-NEXT: 6: eb 19 jmp 0x21 <foo>
+# NOPAD-NEXT: 8: eb 17 jmp 0x21 <foo>
+# NOPAD-NEXT: a: eb 15 jmp 0x21 <foo>
+# NOPAD-NEXT: c: eb 13 jmp 0x21 <foo>
+# NOPAD-NEXT: e: 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 nopw %cs:(%rax,%rax)
+# NOPAD-NEXT: 1d: 0f 1f 00 nopl (%rax)
+# NOPAD-NEXT: 20: cc int3
+
# Demonstrate that we can relax instructions to provide padding, not
# just insert nops. jmps are being used for ease of demonstration.
# CHECK: .text
-# RUN: llvm-mc -filetype=obj -triple i386-pc-linux-gnu %s -x86-pad-max-prefix-size=15 | llvm-objdump -d --section=.text - | FileCheck %s
+# RUN: llvm-mc -filetype=obj -triple i386-pc-linux-gnu %s -x86-pad-max-prefix-size=15 -x86-pad-for-align=1 | llvm-objdump -d - | FileCheck %s
# Check prefix padding generation for all cases on 32 bit x86.
-# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=15 | llvm-objdump -d --section=.text - | FileCheck %s
+# RUN: llvm-mc -mcpu=skylake -filetype=obj -triple x86_64-pc-linux-gnu %s -x86-pad-max-prefix-size=15 -x86-pad-for-align=1 | llvm-objdump -d - | FileCheck %s
# Check prefix padding generation for all cases on 64 bit x86.