[ARM GlobalISel] Legalize G_FMA

For hard float with VFP4, it is legal. Otherwise, we use libcalls.

This needs a bit of support in the LegalizerHelper for soft float
because we didn't handle G_FMA libcalls yet. The support is trivial, as
the only difference between G_FMA and other libcalls that we already
handle is that it has 3 input operands rather than just 2.

llvm-svn: 322366

1 files changed, 121 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/ARM/GlobalISel/arm-legalize-vfp4.mir b/llvm/test/CodeGen/ARM/GlobalISel/arm-legalize-vfp4.mir
new file mode 100644
index 00000000000..5fe0d86b2b4
--- /dev/null
+++ b/llvm/test/CodeGen/ARM/GlobalISel/arm-legalize-vfp4.mir
@@ -0,0 +1,121 @@
+# RUN: llc -mtriple arm-linux-gnueabihf -mattr=+vfp4 -float-abi=hard -global-isel -run-pass=legalizer %s -o - | FileCheck %s -check-prefix CHECK -check-prefix HARD
+# RUN: llc -mtriple arm-linux-gnueabihf -mattr=+vfp2 -float-abi=hard -global-isel -run-pass=legalizer %s -o - | FileCheck %s -check-prefix CHECK -check-prefix SOFT -check-prefix HARD-ABI
+# RUN: llc -mtriple arm-linux-gnueabi -mattr=+vfp4,+soft-float -float-abi=soft -global-isel -run-pass=legalizer %s -o - | FileCheck %s -check-prefix CHECK -check-prefix SOFT -check-prefix SOFT-ABI
+# RUN: llc -mtriple arm-linux-gnu -mattr=+vfp4,+soft-float -float-abi=soft -global-isel -run-pass=legalizer %s -o - | FileCheck %s  -check-prefix CHECK -check-prefix SOFT -check-prefix SOFT-ABI
+--- |
+  define void @test_fma_float() { ret void }
+  define void @test_fma_double() { ret void }
+...
+---
+name:            test_fma_float
+# CHECK-LABEL: name: test_fma_float
+legalized:       false
+# CHECK: legalized: true
+regBankSelected: false
+selected:        false
+tracksRegLiveness: true
+registers:
+  - { id: 0, class: _ }
+  - { id: 1, class: _ }
+  - { id: 2, class: _ }
+  - { id: 3, class: _ }
+body:             |
+  bb.0:
+    liveins: %r0, %r1, %r2
+
+    ; CHECK-DAG: [[X:%[0-9]+]]:_(s32) = COPY %r0
+    ; CHECK-DAG: [[Y:%[0-9]+]]:_(s32) = COPY %r1
+    ; CHECK-DAG: [[Z:%[0-9]+]]:_(s32) = COPY %r2
+    %0(s32) = COPY %r0
+    %1(s32) = COPY %r1
+    %2(s32) = COPY %r2
+    ; HARD: [[R:%[0-9]+]]:_(s32) = G_FMA [[X]], [[Y]], [[Z]]
+    ; SOFT-NOT: G_FMA
+    ; SOFT: ADJCALLSTACKDOWN
+    ; SOFT-ABI-DAG: %r0 = COPY [[X]]
+    ; SOFT-ABI-DAG: %r1 = COPY [[Y]]
+    ; SOFT-ABI-DAG: %r2 = COPY [[Z]]
+    ; SOFT-ABI: BL &fmaf, {{.*}}, implicit %r0, implicit %r1, implicit %r2, implicit-def %r0
+    ; SOFT-ABI: [[R:%[0-9]+]]:_(s32) = COPY %r0
+    ; HARD-ABI-DAG: %s0 = COPY [[X]]
+    ; HARD-ABI-DAG: %s1 = COPY [[Y]]
+    ; HARD-ABI-DAG: %s2 = COPY [[Z]]
+    ; HARD-ABI: BL &fmaf, {{.*}}, implicit %s0, implicit %s1, implicit %s2, implicit-def %s0
+    ; HARD-ABI: [[R:%[0-9]+]]:_(s32) = COPY %s0
+    ; SOFT: ADJCALLSTACKUP
+    ; SOFT-NOT: G_FMA
+    %3(s32) = G_FMA %0, %1, %2
+    ; CHECK: %r0 = COPY [[R]]
+    %r0 = COPY %3(s32)
+    BX_RET 14, %noreg, implicit %r0
+...
+---
+name:            test_fma_double
+# CHECK-LABEL: name: test_fma_double
+legalized:       false
+# CHECK: legalized: true
+regBankSelected: false
+selected:        false
+tracksRegLiveness: true
+registers:
+  - { id: 0, class: _ }
+  - { id: 1, class: _ }
+  - { id: 2, class: _ }
+  - { id: 3, class: _ }
+  - { id: 4, class: _ }
+  - { id: 5, class: _ }
+  - { id: 6, class: _ }
+  - { id: 7, class: _ }
+  - { id: 8, class: _ }
+body:             |
+  bb.0:
+    liveins: %r0, %r1, %r2, %r3
+
+    ; CHECK-DAG: [[X0:%[0-9]+]]:_(s32) = COPY %r0
+    ; CHECK-DAG: [[X1:%[0-9]+]]:_(s32) = COPY %r1
+    ; CHECK-DAG: [[Y0:%[0-9]+]]:_(s32) = COPY %r2
+    ; CHECK-DAG: [[Y1:%[0-9]+]]:_(s32) = COPY %r3
+    %0(s32) = COPY %r0
+    %1(s32) = COPY %r1
+    %2(s32) = COPY %r2
+    %3(s32) = COPY %r3
+    ; HARD-DAG: [[X:%[0-9]+]]:_(s64) = G_MERGE_VALUES [[X0]]
+    ; HARD-DAG: [[Y:%[0-9]+]]:_(s64) = G_MERGE_VALUES [[Y0]]
+    ; HARD-ABI-DAG: [[X:%[0-9]+]]:_(s64) = G_MERGE_VALUES [[X0]]
+    ; HARD-ABI-DAG: [[Y:%[0-9]+]]:_(s64) = G_MERGE_VALUES [[Y0]]
+    %4(s64) = G_MERGE_VALUES %0(s32), %1(s32)
+    %5(s64) = G_MERGE_VALUES %2(s32), %3(s32)
+    ; HARD: [[R:%[0-9]+]]:_(s64) = G_FMA [[X]], [[X]], [[Y]]
+    ; SOFT-NOT: G_FMA
+    ; SOFT: ADJCALLSTACKDOWN
+    ; SOFT-ABI-DAG: %r{{[0-1]}} = COPY [[X0]]
+    ; SOFT-ABI-DAG: %r{{[0-1]}} = COPY [[X1]]
+    ; SOFT-ABI-DAG: %r{{[2-3]}} = COPY [[X0]]
+    ; SOFT-ABI-DAG: %r{{[2-3]}} = COPY [[X1]]
+    ; SOFT-ABI: [[SP1:%[0-9]+]]:_(p0) = COPY %sp
+    ; SOFT-ABI: [[OFF1:%[0-9]+]]:_(s32) = G_CONSTANT i32 0
+    ; SOFT-ABI: [[FI1:%[0-9]+]]:_(p0) = G_GEP [[SP1]], [[OFF1]](s32)
+    ; SOFT-ABI: G_STORE [[Y0]](s32), [[FI1]](p0){{.*}}store 8 into stack
+    ; SOFT-ABI: [[OFF2:%[0-9]+]]:_(s32) = G_CONSTANT i32 4
+    ; SOFT-ABI: [[FI2:%[0-9]+]]:_(p0) = G_GEP [[FI1]], [[OFF2]](s32)
+    ; SOFT-ABI: G_STORE [[Y1]](s32), [[FI2]](p0){{.*}}store 8 into stack
+    ; SOFT-ABI: BL &fma, {{.*}}, implicit %r0, implicit %r1, implicit %r2, implicit %r3, implicit-def %r0, implicit-def %r1
+    ; SOFT-ABI-DAG: [[R0:%[0-9]+]]:_(s32) = COPY %r0
+    ; SOFT-ABI-DAG: [[R1:%[0-9]+]]:_(s32) = COPY %r1
+    ; HARD-ABI-DAG: %d0 = COPY [[X]]
+    ; HARD-ABI-DAG: %d1 = COPY [[X]]
+    ; HARD-ABI-DAG: %d2 = COPY [[Y]]
+    ; HARD-ABI: BL &fma, {{.*}}, implicit %d0, implicit %d1, implicit %d2, implicit-def %d0
+    ; HARD-ABI: [[R:%[0-9]+]]:_(s64) = COPY %d0
+    ; SOFT: ADJCALLSTACKUP
+    ; SOFT-NOT: G_FMA
+    %6(s64) = G_FMA %4, %4, %5
+    ; HARD: [[R0:%[0-9]+]]:_(s32), [[R1:%[0-9]+]]:_(s32) = G_UNMERGE_VALUES [[R]](s64)
+    ; HARD-ABI: [[R0:%[0-9]+]]:_(s32), [[R1:%[0-9]+]]:_(s32) = G_UNMERGE_VALUES [[R]](s64)
+    %7(s32),%8(s32) = G_UNMERGE_VALUES %6(s64)
+    ; CHECK-DAG: %r0 = COPY [[R0]]
+    ; CHECK-DAG: %r1 = COPY [[R1]]
+    %r0 = COPY %7(s32)
+    %r1 = COPY %8(s32)
+    BX_RET 14, %noreg, implicit %r0, implicit %r1
+...