[llvm] [RISCV][CostModel] Remove cost of icmp inst in icmp+select with SFB. (PR #91158)

[Kito Cheng via llvm-commits]

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@@ -0,0 +1,258 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
+; RUN: opt < %s -mtriple=riscv64 -mcpu=sifive-u74 -passes="print<cost-model>" -cost-kind=throughput 2>&1 -disable-output | FileCheck %s --check-prefixes=SFB64
+; RUN: opt < %s -mtriple=riscv64 -mattr=+v,+f -passes="print<cost-model>" -cost-kind=throughput 2>&1 -disable-output | FileCheck %s --check-prefixes=RV64
+
+define i32 @icmp-iselect(i64 %ca, i64 %cb, i32 %a, i32 %b) {
+; SFB64-LABEL: 'icmp-iselect'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %select1
+;
+; RV64-LABEL: 'icmp-iselect'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %select1
+;
+  %cmp1 = icmp slt i64 %ca, %cb
+  %select1 = select i1 %cmp1, i32 %a, i32 %b
+  ret i32 %select1
+}
+
+define i32 @icmp-iselects(i64 %ca, i64 %cb, i32 %a, i32 %b, i32 %c) {
+; SFB64-LABEL: 'icmp-iselects'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select2 = select i1 %cmp1, i32 %a, i32 %c
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %ret = add i32 %select1, %select2
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %ret
+;
+; RV64-LABEL: 'icmp-iselects'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select2 = select i1 %cmp1, i32 %a, i32 %c
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %ret = add i32 %select1, %select2
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %ret
+;
+  %cmp1 = icmp slt i64 %ca, %cb
+  %select1 = select i1 %cmp1, i32 %a, i32 %b
+  %select2 = select i1 %cmp1, i32 %a, i32 %c
+  %ret = add i32 %select1, %select2
+  ret i32 %ret
+}
+
+define i32 @icmp-ifselects(i64 %ca, i64 %cb, i32 %a, i32 %b, float %c, float %d) {
+; SFB64-LABEL: 'icmp-ifselects'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select2 = select i1 %cmp1, float %c, float %d
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %selectint = fptosi float %select2 to i32
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %ret = add i32 %select1, %selectint
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %ret
+;
+; RV64-LABEL: 'icmp-ifselects'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select2 = select i1 %cmp1, float %c, float %d
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %selectint = fptosi float %select2 to i32
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %ret = add i32 %select1, %selectint
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %ret
+;
+  %cmp1 = icmp slt i64 %ca, %cb
+  %select1 = select i1 %cmp1, i32 %a, i32 %b
+  %select2 = select i1 %cmp1, float %c, float %d
+  %selectint = fptosi float %select2 to i32
+  %ret = add i32 %select1, %selectint
+  ret i32 %ret
+}
+
+define i32 @constant-icmp-iselect(i64 %ca, i64 %cb, i32 %a) {
+; SFB64-LABEL: 'constant-icmp-iselect'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 7
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %select1
+;
+; RV64-LABEL: 'constant-icmp-iselect'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %cmp1 = icmp slt i64 %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %cmp1, i32 %a, i32 7
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %select1
+;
+  %cmp1 = icmp slt i64 %ca, %cb
+  %select1 = select i1 %cmp1, i32 %a, i32 7
+  ret i32 %select1
+}
+
+define i32 @fcmp-iselect(float %ca, float %cb, i32 %a, i32 %b) {
+; SFB64-LABEL: 'fcmp-iselect'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fcmp1 = fcmp ogt float %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %fcmp1, i32 %a, i32 %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %select1
+;
+; RV64-LABEL: 'fcmp-iselect'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fcmp1 = fcmp ogt float %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select i1 %fcmp1, i32 %a, i32 %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret i32 %select1
+;
+  %fcmp1 = fcmp ogt float %ca, %cb
+  %select1 = select i1 %fcmp1, i32 %a, i32 %b
+  ret i32 %select1
+}
+
+define float @fcmp-fselect(float %ca, float %cb, float %a, float %b) {
+; SFB64-LABEL: 'fcmp-fselect'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fcmp1 = fcmp ogt float %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fselect1 = select i1 %fcmp1, float %a, float %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret float %fselect1
+;
+; RV64-LABEL: 'fcmp-fselect'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fcmp1 = fcmp ogt float %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fselect1 = select i1 %fcmp1, float %a, float %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret float %fselect1
+;
+  %fcmp1 = fcmp ogt float %ca, %cb
+  %fselect1 = select i1 %fcmp1, float %a, float %b
+  ret float %fselect1
+}
+
+define float @icmp-fselect(i64 %ca, i64 %cb, float %a, float %b) {
+; SFB64-LABEL: 'icmp-fselect'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %icmp1 = icmp slt i64 %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fselect1 = select i1 %icmp1, float %a, float %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret float %fselect1
+;
+; RV64-LABEL: 'icmp-fselect'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %icmp1 = icmp slt i64 %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %fselect1 = select i1 %icmp1, float %a, float %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret float %fselect1
+;
+  %icmp1 = icmp slt i64 %ca, %cb
+  %fselect1 = select i1 %icmp1, float %a, float %b
+  ret float %fselect1
+}
+
+define <2 x i32> @vector-icmp-vector-iselect(<2 x i32> %ca, <2 x i32> %cb, <2 x i32> %a, <2 x i32> %b) {
+; SFB64-LABEL: 'vector-icmp-vector-iselect'
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %icmp = icmp slt <2 x i32> %ca, %cb
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %select1 = select <2 x i1> %icmp, <2 x i32> %a, <2 x i32> %b
+; SFB64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <2 x i32> %select1
+;
+; RV64-LABEL: 'vector-icmp-vector-iselect'
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %icmp = icmp slt <2 x i32> %ca, %cb
+; RV64-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %select1 = select <2 x i1> %icmp, <2 x i32> %a, <2 x i32> %b
+; RV64-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret <2 x i32> %select1
----------------
kito-cheng wrote:

Otherwise it's hard to tell the cost difference is cause by -mcpu or SFB.

https://github.com/llvm/llvm-project/pull/91158