[llvm] [SHT_LLVM_BB_ADDR_MAP][AsmPrinter] Implements PGOAnalysisMap emitting in AsmPrinter with tests. (PR #75202)

[Rahman Lavaee via llvm-commits]

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@@ -0,0 +1,127 @@
+; Check the basic block sections labels option
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-sections=labels | FileCheck %s --check-prefixes=CHECK,BASIC
+
+;; Also verify this holds for all PGO features enabled
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-sections=labels -pgo-analysis-map=func-entry-count,bb-freq,br-prob | FileCheck %s --check-prefixes=CHECK,PGO-ALL,PGO-FEC,PGO-BBF,PGO-BRP
+
+;; Also verify that pgo extension only includes the enabled feature
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-sections=labels -pgo-analysis-map=func-entry-count | FileCheck %s --check-prefixes=CHECK,PGO-FEC,FEC-ONLY
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-sections=labels -pgo-analysis-map=bb-freq | FileCheck %s --check-prefixes=CHECK,PGO-BBF,BBF-ONLY
+; RUN: llc < %s -mtriple=x86_64 -function-sections -unique-section-names=true -basic-block-sections=labels -pgo-analysis-map=br-prob | FileCheck %s --check-prefixes=CHECK,PGO-BRP,BRP-ONLY
+
+
+define void @_Z3bazb(i1 zeroext, i1 zeroext) personality ptr @__gxx_personality_v0 !prof !0  {
+  br i1 %0, label %3, label %8, !prof !1
+
+3:
+  %4 = invoke i32 @_Z3barv()
+          to label %8 unwind label %6
+  br label %10
+
+6:
+  landingpad { ptr, i32 }
+          catch ptr null
+  br label %12
+
+8:
+  %9 = call i32 @_Z3foov()
+  br i1 %1, label %12, label %10, !prof !2
+
+10:
+  %11 = select i1 %1, ptr blockaddress(@_Z3bazb, %3), ptr blockaddress(@_Z3bazb, %12) ; <ptr> [#uses=1]
+  indirectbr ptr %11, [label %3, label %12], !prof !3
+
+12:
+  ret void
+}
+
+declare i32 @_Z3barv() #1
+
+declare i32 @_Z3foov() #1
+
+declare i32 @__gxx_personality_v0(...)
+
+!0 = !{!"function_entry_count", i64 100}
+!1 = !{!"branch_weights", i32 80, i32 20}
+!2 = !{!"branch_weights", i32 70, i32 10}
+!3 = !{!"branch_weights", i32 15, i32 5}
+
+; CHECK:	.section .text._Z3bazb,"ax", at progbits{{$}}
+; CHECK-LABEL:	_Z3bazb:
+; CHECK-LABEL:	.Lfunc_begin0:
+; CHECK-LABEL:	.LBB_END0_0:
+; CHECK-LABEL:	.LBB0_1:
+; CHECK-LABEL:	.LBB_END0_1:
+; CHECK-LABEL:	.LBB0_2:
+; CHECK-LABEL:	.LBB_END0_2:
+; CHECK-LABEL:	.LBB0_3:
+; CHECK-LABEL:	.LBB_END0_3:
+; CHECK-LABEL:	.Lfunc_end0:
+
+; CHECK: 	.section	.llvm_bb_addr_map,"o", at llvm_bb_addr_map,.text._Z3bazb{{$}}
+; CHECK-NEXT:	.byte	2		# version
+; BASIC-NEXT:	.byte	0		# feature
+; PGO-ALL-NEXT:	.byte	7		# feature
+; FEC-ONLY-NEXT:.byte	1		# feature
+; BBF-ONLY-NEXT:.byte	2		# feature
+; BRP-ONLY-NEXT:.byte	4		# feature
+; CHECK-NEXT:	.quad	.Lfunc_begin0	# function address
+; CHECK-NEXT:	.byte	6		# number of basic blocks
+; CHECK-NEXT:	.byte	0		# BB id
+; CHECK-NEXT:	.uleb128 .Lfunc_begin0-.Lfunc_begin0
+; CHECK-NEXT:	.uleb128 .LBB_END0_0-.Lfunc_begin0
+; CHECK-NEXT:	.byte	8
+; CHECK-NEXT:	.byte	1		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_1-.LBB_END0_0
+; CHECK-NEXT:	.uleb128 .LBB_END0_1-.LBB0_1
+; CHECK-NEXT:	.byte	8
+; CHECK-NEXT:	.byte	3		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_2-.LBB_END0_1
+; CHECK-NEXT:	.uleb128 .LBB_END0_2-.LBB0_2
+; CHECK-NEXT:	.byte	8
+; CHECK-NEXT:	.byte	5		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_3-.LBB_END0_2
+; CHECK-NEXT:	.uleb128 .LBB_END0_3-.LBB0_3
+; CHECK-NEXT:	.byte	1
+; CHECK-NEXT:	.byte	4		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_4-.LBB_END0_3
+; CHECK-NEXT:	.uleb128 .LBB_END0_4-.LBB0_4
+; CHECK-NEXT:	.byte	16
+; CHECK-NEXT:	.byte	2		# BB id
+; CHECK-NEXT:	.uleb128 .LBB0_5-.LBB_END0_4
+; CHECK-NEXT:	.uleb128 .LBB_END0_5-.LBB0_5
+; CHECK-NEXT:	.byte	4
+
+;; PGO Analysis Map
+; PGO-FEC-NEXT:	.byte	100		# function entry count
+; PGO-BBF-NEXT:	.ascii	"\271\235\376\332\245\200\356\017"	# basic block frequency
----------------
rlavaee wrote:

I am scratching my head around why function entry count is encoded as simple byte but basic block frequencies are encoded as ascii. Shouldn't we at least have 20 and 80 as block frequencies of two blocks?

https://github.com/llvm/llvm-project/pull/75202