[llvm-mca] Default the output asm dialect used by the instruction printer to the input asm dialect.
The instruction printer used by llvm-mca to generate the performance report now
defaults the output assembly format to the format used for the input assembly
file.
On x86, the asm format can be either AT&T or Intel, depending on the
presence/absence of directive `.intel_syntax`.
Users can still specify a different assembly dialect with the command line flag
-output-asm-variant=<uint>.
llvm-svn: 330733
diff --git a/llvm/test/tools/llvm-mca/X86/intel-syntax.s b/llvm/test/tools/llvm-mca/X86/intel-syntax.s
new file mode 100644
index 0000000..7513c42
--- /dev/null
+++ b/llvm/test/tools/llvm-mca/X86/intel-syntax.s
@@ -0,0 +1,37 @@
+# NOTE: Assertions have been autogenerated by utils/update_mca_test_checks.py
+# RUN: llvm-mca -mtriple=x86_64-unknown-unknown -mcpu=btver2 -resource-pressure=false < %s | FileCheck %s -check-prefixes=ALL,INTEL
+# RUN: llvm-mca -mtriple=x86_64-unknown-unknown -mcpu=btver2 -resource-pressure=false -output-asm-variant=0 < %s | FileCheck %s -check-prefixes=ALL,ATT
+# RUN: llvm-mca -mtriple=x86_64-unknown-unknown -mcpu=btver2 -resource-pressure=false -output-asm-variant=1 < %s | FileCheck %s -check-prefixes=ALL,INTEL
+
+ .intel_syntax noprefix
+ mov eax, 1
+ mov ebx, 0ffh
+ imul esi, edi
+ lea eax, [rsi + rdi]
+
+# ALL: Iterations: 100
+# ALL-NEXT: Instructions: 400
+# ALL-NEXT: Total Cycles: 305
+# ALL-NEXT: Dispatch Width: 2
+# ALL-NEXT: IPC: 1.31
+
+# ALL: Instruction Info:
+# ALL-NEXT: [1]: #uOps
+# ALL-NEXT: [2]: Latency
+# ALL-NEXT: [3]: RThroughput
+# ALL-NEXT: [4]: MayLoad
+# ALL-NEXT: [5]: MayStore
+# ALL-NEXT: [6]: HasSideEffects
+
+# INTEL: [1] [2] [3] [4] [5] [6] Instructions:
+# INTEL-NEXT: 1 1 0.50 mov eax, 1
+# INTEL-NEXT: 1 1 0.50 mov ebx, 255
+# INTEL-NEXT: 2 3 1.00 imul esi, edi
+# INTEL-NEXT: 1 1 0.50 lea eax, [rsi + rdi]
+
+# ATT: [1] [2] [3] [4] [5] [6] Instructions:
+# ATT-NEXT: 1 1 0.50 movl $1, %eax
+# ATT-NEXT: 1 1 0.50 movl $255, %ebx
+# ATT-NEXT: 2 3 1.00 imull %edi, %esi
+# ATT-NEXT: 1 1 0.50 leal (%rsi,%rdi), %eax
+