[CompactUnwind] Fix register encoding logic

Fix a compact unwind encoding logic bug which would try to encode
more callee saved registers than it should, leading to early bail out
in the encoding logic and abusive use of DWARF frame mode unnecessarily.

Also remove no-compact-unwind.ll which was testing the wrong thing
based on this bug and move it to valid 'compact unwind' tests. Added
other few more tests too.

llvm-svn: 223676

1 files changed, 79 insertions, 9 deletions

diff --git a/llvm/test/CodeGen/X86/compact-unwind.ll b/llvm/test/CodeGen/X86/compact-unwind.ll
index 9d3a1257288..d3b89a54e0b 100644
--- a/llvm/test/CodeGen/X86/compact-unwind.ll
+++ b/llvm/test/CodeGen/X86/compact-unwind.ll
@@ -1,12 +1,20 @@
 ; RUN: llc < %s -disable-fp-elim -mtriple x86_64-apple-darwin11 -mcpu corei7 | FileCheck -check-prefix=ASM %s
 ; RUN: llc < %s -disable-fp-elim -mtriple x86_64-apple-darwin11 -mcpu corei7 -filetype=obj -o - \
-; RUN:  | llvm-objdump -triple x86_64-apple-darwin11 -s - \
+; RUN:  | llvm-objdump -triple x86_64-apple-darwin11 -unwind-info - \
 ; RUN:  | FileCheck -check-prefix=CU %s
 ; RUN: llc < %s -disable-fp-elim -mtriple x86_64-apple-darwin11 -mcpu corei7 \
 ; RUN:  | llvm-mc -triple x86_64-apple-darwin11 -filetype=obj -o - \
-; RUN:  | llvm-objdump -triple x86_64-apple-darwin11 -s - \
+; RUN:  | llvm-objdump -triple x86_64-apple-darwin11 -unwind-info - \
 ; RUN:  | FileCheck -check-prefix=FROM-ASM %s
 
+; RUN: llc < %s -mtriple x86_64-apple-macosx10.8.0 -mcpu corei7 -filetype=obj -o - \
+; RUN:  | llvm-objdump -triple x86_64-apple-macosx10.8.0 -unwind-info - \
+; RUN:  | FileCheck -check-prefix=NOFP-CU %s
+; RUN: llc < %s -mtriple x86_64-apple-darwin11 -mcpu corei7 \
+; RUN:  | llvm-mc -triple x86_64-apple-darwin11 -filetype=obj -o - \
+; RUN:  | llvm-objdump -triple x86_64-apple-darwin11 -unwind-info - \
+; RUN:  | FileCheck -check-prefix=NOFP-FROM-ASM %s
+
 %ty = type { i8* }
 
 @gv = external global i32
@@ -17,15 +25,19 @@
 ; Even though we can't encode %rax into the compact unwind, We still want to be
 ; able to generate a compact unwind encoding in this particular case.
 
-; CU:      Contents of section __compact_unwind:
-; CU-NEXT: 0020 00000000 00000000 1e000000 01000101
-; CU-NEXT: 0030 00000000 00000000 00000000 00000000
+; CU:    Contents of __compact_unwind section:
+; CU-NEXT:      Entry at offset 0x0:
+; CU-NEXT:        start:                0x0 _test0
+; CU-NEXT:        length:               0x1e
+; CU-NEXT:        compact encoding:     0x01010001
 
-; FROM-ASM:      Contents of section __compact_unwind:
-; FROM-ASM-NEXT: 0020 00000000 00000000 1e000000 01000101
-; FROM-ASM-NEXT: 0030 00000000 00000000 00000000 00000000
+; FROM-ASM:    Contents of __compact_unwind section:
+; FROM-ASM-NEXT:      Entry at offset 0x0:
+; FROM-ASM-NEXT:        start:                0x0 _test0
+; FROM-ASM-NEXT:        length:               0x1e
+; FROM-ASM-NEXT:        compact encoding:     0x01010001
 
-define i8* @foo(i64 %size) {
+define i8* @test0(i64 %size) {
   %addr = alloca i64, align 8
   %tmp20 = load i32* @gv, align 4
   %tmp21 = call i32 @bar()
@@ -39,3 +51,61 @@ define i8* @foo(i64 %size) {
 }
 
 declare i32 @bar()
+
+%"struct.dyld::MappedRanges" = type { [400 x %struct.anon], %"struct.dyld::MappedRanges"* }
+%struct.anon = type { %class.ImageLoader*, i64, i64 }
+%class.ImageLoader = type { i32 (...)**, i8*, i8*, i32, i64, i64, i32, i32, %"struct.ImageLoader::recursive_lock"*, i16, i16, [4 x i8] }
+%"struct.ImageLoader::recursive_lock" = type { i32, i32 }
+
+@G1 = external hidden global %"struct.dyld::MappedRanges", align 8
+
+declare void @OSMemoryBarrier() optsize
+
+; Test the code below uses UNWIND_X86_64_MODE_STACK_IMMD compact unwind
+; encoding.
+
+; NOFP-CU:      Entry at offset 0x20:
+; NOFP-CU-NEXT:        start:                0x1d _test1
+; NOFP-CU-NEXT:        length:               0x42
+; NOFP-CU-NEXT:        compact encoding:     0x02040c0a
+
+; NOFP-FROM-ASM:      Entry at offset 0x20:
+; NOFP-FROM-ASM-NEXT:        start:                0x1d _test1
+; NOFP-FROM-ASM-NEXT:        length:               0x42
+; NOFP-FROM-ASM-NEXT:        compact encoding:     0x02040c0a
+
+define void @test1(%class.ImageLoader* %image) optsize ssp uwtable {
+entry:
+  br label %for.cond1.preheader
+
+for.cond1.preheader:                              ; preds = %for.inc10, %entry
+  %p.019 = phi %"struct.dyld::MappedRanges"* [ @G1, %entry ], [ %1, %for.inc10 ]
+  br label %for.body3
+
+for.body3:                                        ; preds = %for.inc, %for.cond1.preheader
+  %indvars.iv = phi i64 [ 0, %for.cond1.preheader ], [ %indvars.iv.next, %for.inc ]
+  %image4 = getelementptr inbounds %"struct.dyld::MappedRanges"* %p.019, i64 0, i32 0, i64 %indvars.iv, i32 0
+  %0 = load %class.ImageLoader** %image4, align 8
+  %cmp5 = icmp eq %class.ImageLoader* %0, %image
+  br i1 %cmp5, label %if.then, label %for.inc
+
+if.then:                                          ; preds = %for.body3
+  tail call void @OSMemoryBarrier() optsize
+  store %class.ImageLoader* null, %class.ImageLoader** %image4, align 8
+  br label %for.inc
+
+for.inc:                                          ; preds = %if.then, %for.body3
+  %indvars.iv.next = add i64 %indvars.iv, 1
+  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+  %exitcond = icmp eq i32 %lftr.wideiv, 400
+  br i1 %exitcond, label %for.inc10, label %for.body3
+
+for.inc10:                                        ; preds = %for.inc
+  %next = getelementptr inbounds %"struct.dyld::MappedRanges"* %p.019, i64 0, i32 1
+  %1 = load %"struct.dyld::MappedRanges"** %next, align 8
+  %cmp = icmp eq %"struct.dyld::MappedRanges"* %1, null
+  br i1 %cmp, label %for.end11, label %for.cond1.preheader
+
+for.end11:                                        ; preds = %for.inc10
+  ret void
+}